merge: integrate hybrid domain architecture

refactor(chart): introduce hybrid domain architecture
feat(chart): support configurable plot margins
2026-08-07 15:59:38 +08:00 · 2026-08-07 15:59:26 +08:00 · 2026-08-05 15:16:52 +08:00 · 2026-08-05 10:58:40 +08:00 · 2026-08-04 11:28:42 +08:00 · 2026-07-31 12:07:08 +08:00
65 changed files with 2461 additions and 456 deletions
--- a/README.md
+++ b/README.md
@@ -12,6 +12,9 @@

 最新稳定版 Demo：<https://lqycustomsite.online/waveform-analysis/>

+本地运行 `pnpm dev` 后，可通过
+<http://127.0.0.1:5173/#/fixed-y-domain> 查看固定振幅上下限示例。
+
 ## 特性

 - Vue 3 Composition API + TypeScript，支持按需导入 `WaveformChart`
@@ -22,6 +25,7 @@
 - 缩放过程事件、缩放结束按可视区间加载和视口重置
 - 可选的空格拖拽平移，默认关闭并隔离多图表实例
 - 多系列图例、受控显隐、网格分页和最多四根 Y 轴
+- 自动 Y 轴范围，以及全局、按轨道或按系列配置的固定振幅范围
 - 按轨道控制水平/垂直网格线的显隐与颜色
 - 受控标注、右键编辑、拖拽避让和自定义颜色
 - 标题、图框、坐标轴、零值参考线、净图和渲染参数可配置
@@ -92,39 +96,41 @@ const data = ref<WaveformData>({

 ### Props

-| Prop                              | 类型                                        | 默认值                                                  | 说明                              |
-| --------------------------------- | ------------------------------------------- | ------------------------------------------------------- | --------------------------------- |
-| `data`                            | `WaveformData`                              | 必填                                                    | 波形数据                          |
-| `displayMode`                     | `'independent' \| 'separated' \| 'compact'` | `'independent'`                                         | 图框布局                          |
-| `overlayMode`                     | `'single-axis' \| 'multi-axis'`             | `'single-axis'`                                         | 叠加曲线的 Y 轴模式               |
-| `timeUnit`                        | `'s' \| 'ms'`                               | `'ms'`                                                  | 坐标轴和 tooltip 展示单位         |
-| `xLabel` / `yLabel`               | `string`                                    | `时间（timeUnit）` / `'幅值'`                           | 坐标轴名称                        |
-| `lineColor`                       | `string`                                    | `'#0960bd'`                                             | 单波形默认颜色                    |
-| `width` / `height`                | `number`                                    | 自适应                                                  | 组件总尺寸，单位为 CSS 像素       |
-| `zoomable` / `showTooltip`        | `boolean`                                   | `true` / `true`                                         | 缩放和数值 tooltip 开关           |
-| `pannable`                        | `boolean`                                   | `false`                                                 | 空格拖拽平移开关                  |
-| `minZoomSpan`                     | `number`                                    | 未设置                                                  | 最小缩放跨度，使用原始 X 数据单位 |
-| `minVisiblePoints`                | `number`                                    | `0`                                                     | 缩放后至少保留的不同 X 坐标数     |
-| `initialXDomain`                  | `[number, number]`                          | 未设置                                                  | 所有图框的初始 X 范围             |
-| `initialXDomains`                 | `Record<string, [number, number]>`          | 未设置                                                  | 按 track/series ID 配置初始范围   |
-| `grid`                            | `WaveformGridOptions`                       | `{ rowCount: 2, columnCount: 1, showPagination: true }` | 网格和分页                        |
-| `axes`                            | `WaveformAxesOptions`                       | 轴线均显示                                              | X/Y 轴基线显隐                    |
-| `rendering`                       | `WaveformRenderingOptions`                  | `{}`                                                    | 降采样与点/误差棒间距             |
-| `title` / `legend` / `frameStyle` | 对应公开类型                                | 未设置                                                  | 标题、图例和图框样式              |
-| `frameNumber`                     | `string \| number`                          | 未设置                                                  | 图框水印内容                      |
-| `zeroLine`                        | `WaveformZeroLineOptions`                   | `{ visible: false }`                                    | 零值参考线显隐与样式              |
-| `cleanView`                       | `boolean`                                   | `false`                                                 | 仅保留波形的净图模式              |
-| `presentationMode`                | `boolean`                                   | `false`                                                 | 禁用绘图区交互的展示模式          |
-| `annotations`                     | `WaveformAnnotation[]`                      | `[]`                                                    | 受控标注数据                      |
-| `annotationsVisible`              | `boolean`                                   | `true`                                                  | 标注图层显隐                      |
-| `interactionMode`                 | `'zoom' \| 'annotation'`                    | `'zoom'`                                                | 左键交互模式                      |
-| `hiddenSeriesIds`                 | `string[]`                                  | 未设置                                                  | 受控隐藏系列 ID                   |
-| `defaultHiddenSeriesIds`          | `string[]`                                  | `[]`                                                    | 非受控模式的初始隐藏系列          |
+| Prop                              | 类型                                        | 默认值                                                  | 说明                               |
+| --------------------------------- | ------------------------------------------- | ------------------------------------------------------- | ---------------------------------- |
+| `data`                            | `WaveformData`                              | 必填                                                    | 波形数据                           |
+| `displayMode`                     | `'independent' \| 'separated' \| 'compact'` | `'independent'`                                         | 图框布局                           |
+| `overlayMode`                     | `'single-axis' \| 'multi-axis'`             | `'single-axis'`                                         | 叠加曲线的 Y 轴模式                |
+| `timeUnit`                        | `'s' \| 'ms'`                               | `'ms'`                                                  | 坐标轴和 tooltip 展示单位          |
+| `xLabel` / `yLabel`               | `string`                                    | `时间（timeUnit）` / `'幅值'`                           | 坐标轴名称                         |
+| `lineColor`                       | `string`                                    | `'#0960bd'`                                             | 单波形默认颜色                     |
+| `width` / `height`                | `number`                                    | 自适应                                                  | 组件总尺寸，单位为 CSS 像素        |
+| `zoomable` / `showTooltip`        | `boolean`                                   | `true` / `true`                                         | 缩放和数值 tooltip 开关            |
+| `pannable`                        | `boolean`                                   | `false`                                                 | 空格拖拽平移开关                   |
+| `minZoomSpan`                     | `number`                                    | 未设置                                                  | 最小缩放跨度，使用原始 X 数据单位  |
+| `minVisiblePoints`                | `number`                                    | `0`                                                     | 缩放后至少保留的不同 X 坐标数      |
+| `initialXDomain`                  | `[number, number]`                          | 未设置                                                  | 所有图框的初始 X 范围              |
+| `initialXDomains`                 | `Record<string, [number, number]>`          | 未设置                                                  | 按 track/series ID 配置初始范围    |
+| `yDomain`                         | `[number, number]`                          | 未设置                                                  | 所有波形的固定 Y 轴范围            |
+| `yDomains`                        | `Record<string, [number, number]>`          | 未设置                                                  | 按 track/series ID 配置固定范围    |
+| `grid`                            | `WaveformGridOptions`                       | `{ rowCount: 2, columnCount: 1, showPagination: true }` | 网格和分页                         |
+| `axes`                            | `WaveformAxesOptions`                       | 轴线均显示                                              | X/Y 轴基线显隐与 X 轴 label 格式化 |
+| `rendering`                       | `WaveformRenderingOptions`                  | `{}`                                                    | 降采样与点/误差棒间距              |
+| `title` / `legend` / `frameStyle` | 对应公开类型                                | 未设置                                                  | 标题、图例和图框样式               |
+| `frameNumber`                     | `string \| number`                          | 未设置                                                  | 图框水印内容                       |
+| `zeroLine`                        | `WaveformZeroLineOptions`                   | `{ visible: false }`                                    | 零值参考线显隐与样式               |
+| `cleanView`                       | `boolean`                                   | `false`                                                 | 保留波形、图框和刻度的净图模式     |
+| `presentationMode`                | `boolean`                                   | `false`                                                 | 禁用绘图区交互的展示模式           |
+| `annotations`                     | `WaveformAnnotation[]`                      | `[]`                                                    | 受控标注数据                       |
+| `annotationsVisible`              | `boolean`                                   | `true`                                                  | 标注图层显隐                       |
+| `interactionMode`                 | `'zoom' \| 'annotation'`                    | `'zoom'`                                                | 左键交互模式                       |
+| `hiddenSeriesIds`                 | `string[]`                                  | 未设置                                                  | 受控隐藏系列 ID                    |
+| `defaultHiddenSeriesIds`          | `string[]`                                  | `[]`                                                    | 非受控模式的初始隐藏系列           |

 所有公开类型均可从包入口导入，例如 `WaveformData`、`WaveformSeries`、
 `WaveformAnnotation`、`WaveformLineStyle`、`WaveformRenderingOptions`、
-`WaveformAxesOptions`、`WaveformZeroLineOptions`、`WaveformGridOptions` 和
-`WaveformGridTrackLines`。
+`WaveformAxesOptions`、`WaveformXAxisLabelFormatter`、`WaveformZeroLineOptions`、
+`WaveformGridOptions` 和 `WaveformGridTrackLines`。

 ### 数据结构

@@ -177,11 +183,43 @@ import 'waveform-analysis/style.css'
 </template>
 ```

+### 固定振幅上下限
+
+未传入 Y 轴范围时，组件继续根据当前可见系列及其误差棒自动计算范围。传入 `yDomain`
+后，所有波形使用同一个固定范围；超出范围的部分只在绘图区裁剪，不会过滤或修改原始数据：
+
+```vue
+<WaveformChart :data="chartData" :y-domain="[-80, 80]" />
+```
+
+多通道可以通过 `yDomains` 按稳定的 `trackId` 或 `seriesId` 分别配置：
+
+```vue
+<WaveformChart
+  :data="chartData"
+  :y-domain="[-100, 100]"
+  :y-domains="{
+    voltage: [-65, 65],
+    current: [-260, 260],
+  }"
+/>
+```
+
+范围优先级为 `trackId` 配置、`seriesId` 配置、全局 `yDomain`、数据自动范围。上下限必须
+是两个有限且不相等的数字；倒序范围会自动调整为升序，无效配置会回退到下一优先级。
+固定范围会精确作为坐标域使用，不会经过 D3 的 `nice()` 扩展。
+
+单值轴叠加模式会合并同一根轴上所有可见系列的有效范围；多值轴模式按系列分别使用配置，
+超过四根轴后复用第 4 根轴的系列会取范围并集。隐藏系列不参与公共范围合并。
+
+固定范围存在时，对应图框的 Y 轴不会被平移或视口重置覆盖；X 轴缩放、平移和重置保持原有
+行为。运行时更新或移除 `yDomain` / `yDomains` 会立即重新布局，移除后恢复自动范围。
+
 ### 缩放后按可视区间加载数据

 组件支持 Plotly 风格的矩形框选缩放：在 zoom 模式下按住鼠标左键拖拽，松开后同时缩放
 X/Y 轴；设置 `pannable` 后，指针位于图表内时按住空格键拖拽可平移当前视口。
-鼠标滚轮仍可放大，双击恢复完整视口。
+鼠标滚轮可放大和缩小，双击恢复完整视口。
 组件会在滚轮或框选缩放结束后触发 `zoom-end`，调用方可以使用端点请求后端，再通过
 `data` 传回新数据。独立分图模式还会包含 `trackIndex` 和稳定的 `seriesIds`。

@@ -411,9 +449,10 @@ scale 定位零线：
 `dash` 直接对应 SVG 的 `stroke-dasharray`；传入空字符串可显示实线。无效或非正数的
 `width` 会回退到 `1`。

-设置 `cleanView` 后，组件隐藏标题内容、图例、网格、坐标轴、轴标签、图框背景与边框、帧水印、
-零值参考线、标注和分页器，同时保留原图的标题区域、边距和波形尺寸。缩放、悬浮、十字线和
-tooltip 仍然可用，切换回普通模式后原有配置和标注不会丢失：
+设置 `cleanView` 后，组件保留波形、图框边框、X/Y 轴刻度及刻度值，并隐藏标题内容、图例、
+网格、轴标签、图框背景、帧水印、零值参考线、标注和分页器。原图的标题区域、边距和波形
+尺寸保持不变；缩放、悬浮、十字线和 tooltip 仍然可用，切换回普通模式后原有配置和标注
+不会丢失：

 ```vue
 <WaveformChart :data="chartData" :clean-view="cleanViewEnabled" />
@@ -469,6 +508,30 @@ tooltip 仍然可用，切换回普通模式后原有配置和标注不会丢失
 />
 ```

+X 轴刻度和左右端点默认先按 `timeUnit` 转换为秒或毫秒，再显示为无千分位、无科学计数法的
+完整普通十进制值，不会四舍五入为整数。可通过 `axes.x.labelFormatter` 对显示值做运算和格式化：
+
+```vue
+<WaveformChart
+  :data="chartData"
+  :axes="{
+    x: {
+      labelFormatter: (value, context) =>
+        `${context.kind === 'tick' ? '' : '[' + context.kind + '] '}${(value / 1000).toFixed(3)}`,
+    },
+  }"
+/>
+```
+
+formatter 首参是已按 `timeUnit` 换算的数值；上下文包含 `kind`（`tick`、`start` 或 `end`）、
+原始 `rawValue`、`timeUnit`、原始可视域 `domain` 和换算后的 `displayDomain`。formatter 只决定
+label 文本，不改变刻度位置、源数据、缩放域或事件中的原始 X 坐标。
+
+Demo 左侧“网格与轴线”支持直接切换数值或固定时间格式。数值模式可设置运算倍率和小数位数；
+固定时间模式输出 `YYYY-MM-DD HH:mm:ss[.SSS]`，可选择中国标准时间、本地时区或 UTC，并控制
+是否显示毫秒。时间戳数据仍按组件的秒坐标契约传入，使用默认毫秒显示单位时 formatter 会收到
+可直接传给 `Date` 的毫秒时间戳。
+
 `interactionMode` 可选 `zoom` 或 `annotation`，默认使用缩放模式。右键绘图区可直接打开
 标注编辑器，无需切换交互模式。`zoomable`、`pannable` 和 `showTooltip` 可分别控制缩放、
 空格拖拽平移和 tooltip；平移默认关闭。
@@ -564,7 +627,7 @@ async function importAnnotationFile(file: File) {
 字段无效时会抛出 `TypeError`，不会返回部分结果。导入包含未知 `seriesId` 的标注是允许的，
 对应曲线加载后会恢复显示。文件选择、错误提示和下载由业务层实现。

-X、Y 轴会根据各自完整显示域选择格式：最大绝对值在 `[0.01, 100)` 时显示两位普通小数；大于等于 `100`，或大于 `0` 且小于 `0.01` 时，刻度显示两位缩放值，并在轴末端单独显示共享倍率 `E±NN`。X 轴先按 `timeUnit` 转换为秒或毫秒再判断范围，多 Y 轴则分别计算倍率。tooltip 使用最多 4 位小数的本地化普通数字；标注编辑器的 X 坐标跟随 `timeUnit` 并固定 3 位小数，Y 坐标显示完整普通十进制。所有格式化都只发生在展示层，内部坐标值保持原始精度。
+X 轴刻度和左右端点先按 `timeUnit` 转换为秒或毫秒，再显示为不带分组符和科学计数法的完整普通十进制值，并可通过 `axes.x.labelFormatter` 自定义。Y 轴会根据完整显示域选择格式：最大绝对值在 `[0.01, 100)` 时显示两位普通小数；大于等于 `100`，或大于 `0` 且小于 `0.01` 时，刻度显示两位缩放值，并在轴末端单独显示共享倍率 `E±NN`，多 Y 轴分别计算倍率。tooltip 使用最多 4 位小数的本地化普通数字并省略无意义尾零；标注编辑器的 X 坐标跟随 `timeUnit` 并固定 3 位小数，Y 坐标显示完整普通十进制。所有格式化都只发生在展示层，内部坐标值保持原始精度。
 标注框默认布局在采样点正上方，只做绘图区边界裁剪；文本框通过连接箭头指向标注位置，多个标注重叠时可通过拖动手动避让。

 ## 事件
@@ -589,7 +652,8 @@ X、Y 轴会根据各自完整显示域选择格式：最大绝对值在 `[0.01,
 - `src/index.ts`：组件库公开入口和工具函数导出
 - `src/components/WaveformChart.vue`：图表容器、缩放、tooltip、图例和标注编排
 - `src/components/{core,data,rendering,interaction,annotation}`：数据、布局、渲染和交互模块
- `src/App.vue`：可交互 demo，`src/data` 中提供示例波形数据
+- `src/App.vue`：综合可交互 demo，`src/data` 中提供示例波形数据
+- `src/router.ts`：Demo 路由；`src/views/FixedYDomainDemo.vue` 为固定振幅范围示例

 ## 本地开发

--- a/docs/architecture.md
+++ b/docs/architecture.md
@@ -0,0 +1,36 @@
+# Architecture
+
+Waveform Analysis uses a hybrid architecture. Vue Composition API remains the orchestration
+boundary, while classes are reserved for domain objects with lifecycle or algorithm-selection
+invariants.
+
+## Boundaries
+
+- `useWaveformChartController` is the facade for the chart. It composes composables and exposes the
+  existing reactive controller surface; it owns no independent copy of component props.
+- `useWaveformViewport` keeps refs, computed values, pointer events, DOM capture, D3 coordinates,
+  and emitted events. `ViewportInteractionStateMachine` is its domain collaborator: it has no Vue
+  or DOM dependency and accepts only legal `begin`, `move`, `finish`, `cancel`, and `reset`
+  transitions. Its state is a `box`/`pan` discriminated union, with `null` representing idle.
+- `RenderablePointSelectionStrategy` defines the replaceable rendering algorithm boundary.
+  `CompletePointSelectionStrategy` preserves the complete visible source range and
+  `PeakPreservingPointSelectionStrategy` preserves first/minimum/maximum/last points per bucket.
+  `resolveRenderablePointSelectionStrategy` resolves and reuses the strategy from rendering options. The
+  existing `selectRenderablePoints` function remains the compatibility facade used by rendering.
+- `normalizeWaveformData` and `normalizeWaveformSeries` are functional adapters from public data
+  shapes to the internal series model. `buildTrackLayouts` remains a functional builder because
+  layout construction is a stateless calculation, not a long-lived object.
+
+## Vue Integration
+
+The state-machine instance is stored in `shallowRef(markRaw(...))`. Vue receives defensive state
+snapshots through a shallow ref, while SVG overlay elements remain in the composable as DOM
+resources. Presentation mode, annotation editing, scales, domains, ticks, formatting, and other
+stateless calculations stay in their existing computed/composable or function boundaries.
+
+## Constraints
+
+Do not create classes solely to wrap Composition API refs, props, lifecycle hooks, D3 selections, or
+pure mathematical helpers. Do not add inheritance trees, global event buses, service locators, or
+duplicate prop state. A new class must own a real invariant or replaceable algorithm and must be
+used by a production path with isolated tests.
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
  "name": "waveform-analysis",
-  "version": "0.1.24",
+  "version": "0.1.30",
  "main": "./dist/index.cjs",
  "module": "./dist/index.js",
  "types": "./dist/types/index.d.ts",
@@ -38,6 +38,7 @@
  "dependencies": {
    "ant-design-vue": "3.2.20",
    "d3": "^7.9.0",
+    "vue-router": "^4.6.4",
    "vue3-colorpicker": "^2.3.0"
  },
  "peerDependencies": {
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -14,6 +14,9 @@ importers:
      d3:
        specifier: ^7.9.0
        version: 7.9.0
+      vue-router:
+        specifier: ^4.6.4
+        version: 4.6.4(vue@3.5.40(typescript@6.0.3))
      vue3-colorpicker:
        specifier: ^2.3.0
        version: 2.3.0(@aesoper/normal-utils@0.1.5)(@popperjs/core@2.11.8)(@vueuse/core@10.11.1(vue@3.5.40(typescript@6.0.3)))(gradient-parser@1.2.0)(lodash-es@4.18.1)(tinycolor2@1.6.0)(vue-types@4.2.1(vue@3.5.40(typescript@6.0.3)))(vue@3.5.40(typescript@6.0.3))
@@ -632,6 +635,9 @@ packages:
  '@vue/compiler-ssr@3.5.40':
    resolution: {integrity: sha512-rrE5xiXG663+vHCHa3J9p2z5OcBRjXmoqenprJxAFQxg5pSshzeBiCE6pu46axapRJ2Adk0YDA2BRZVjiHXnhg==}

+  '@vue/devtools-api@6.6.4':
+    resolution: {integrity: sha512-sGhTPMuXqZ1rVOk32RylztWkfXTRhuS7vgAKv0zjqk8gbsHkJ7xfFf+jbySxt7tWObEJwyKaHMikV/WGDiQm8g==}
+
  '@vue/language-core@3.3.7':
    resolution: {integrity: sha512-LzmkKinXAMMoh8Jfi/jMUSDUjuPdv8mynH5WJGKfXyZtDw3hQ6GBaoI6Bcnl/Xqlu32q/0Z6i/trp4VXykzyLw==}

@@ -1704,6 +1710,11 @@ packages:
    peerDependencies:
      eslint: ^8.57.0 || ^9.0.0 || ^10.0.0

+  vue-router@4.6.4:
+    resolution: {integrity: sha512-Hz9q5sa33Yhduglwz6g9skT8OBPii+4bFn88w6J+J4MfEo4KRRpmiNG/hHHkdbRFlLBOqxN8y8gf2Fb0MTUgVg==}
+    peerDependencies:
+      vue: ^3.5.0
+
  vue-tsc@3.3.7:
    resolution: {integrity: sha512-+C+rgD49wAQ5bUTl2sp5a8Bzg4YoldMNXM+g7CFe604MYcQ8PrZPMQhIjJSzKXtPBCa+C5ayMipqjbA7splekQ==}
    hasBin: true
@@ -2378,6 +2389,8 @@ snapshots:
      '@vue/compiler-dom': 3.5.40
      '@vue/shared': 3.5.40

+  '@vue/devtools-api@6.6.4': {}
+
  '@vue/language-core@3.3.7':
    dependencies:
      '@volar/language-core': 2.4.28
@@ -3386,6 +3399,11 @@ snapshots:
    transitivePeerDependencies:
      - supports-color

+  vue-router@4.6.4(vue@3.5.40(typescript@6.0.3)):
+    dependencies:
+      '@vue/devtools-api': 6.6.4
+      vue: 3.5.40(typescript@6.0.3)
+
  vue-tsc@3.3.7(typescript@6.0.3):
    dependencies:
      '@volar/typescript': 2.4.28
--- a/src/App.vue
+++ b/src/App.vue
@@ -14,6 +14,7 @@ import {
  type WaveformLegendOrientation,
  type WaveformLegendPosition,
  type WaveformOverlayMode,
+  type WaveformPlotMargin,
  type WaveformTitleOptions,
  type WaveformZoomEndPayload,
  type WaveformZeroLineOptions,
@@ -23,6 +24,7 @@ import { createSimulatedWaveformData } from './data/simulatedWaveforms'
 import DemoChartHost from './demo/DemoChartHost.vue'
 import DemoControlPanel from './demo/DemoControlPanel.vue'
 import type { DemoChartModel, DemoControlPanelModel } from './demo/types'
+import { useDemoXAxisLabelControls } from './demo/useDemoXAxisLabelControls'

 const fullChartData = createSimulatedWaveformData()
 const displayMode = ref<WaveformDisplayMode>('independent')
@@ -40,11 +42,14 @@ const verticalGridVisible = ref(true)
 const verticalGridColor = ref('#dfe5ef')
 const xAxisLineVisible = ref(false)
 const yAxisLineVisible = ref(false)
+const { controlModel: xAxisLabelControlModel, xAxisLabelFormatter } = useDemoXAxisLabelControls()
 const annotations = ref<WaveformAnnotation[]>([])
 const annotationsVisible = ref(true)
 const cleanView = ref(false)
 const presentationMode = ref(false)
 const showTooltip = ref(true)
+const plotMarginTop = ref(18)
+const plotMarginBottom = ref(52)
 const zeroLineVisible = ref(false)
 const zeroLineColor = ref('#98a2b3')
 const zeroLineWidth = ref(1)
@@ -112,7 +117,10 @@ const frameStyle = computed<WaveformFrameStyle>(() => ({
  backgroundColor: frameBackgroundColor.value,
 }))
 const axes = computed<WaveformAxesOptions>(() => ({
-  x: { lineVisible: xAxisLineVisible.value },
+  x: {
+    lineVisible: xAxisLineVisible.value,
+    ...(xAxisLabelFormatter.value ? { labelFormatter: xAxisLabelFormatter.value } : {}),
+  },
  y: { lineVisible: yAxisLineVisible.value },
 }))
 const zeroLine = computed<WaveformZeroLineOptions>(() => ({
@@ -121,6 +129,10 @@ const zeroLine = computed<WaveformZeroLineOptions>(() => ({
  width: zeroLineWidth.value,
  dash: zeroLineDash.value,
 }))
+const plotMargin = computed<WaveformPlotMargin>(() => ({
+  top: plotMarginTop.value,
+  bottom: plotMarginBottom.value,
+}))

 const initialXValues = normalizeWaveformSeries(fullChartData).flatMap((series) =>
  series.points.map((point) => point.x),
@@ -289,6 +301,8 @@ const controlPanelModel = reactive({
  displayMode,
  overlayMode,
  showTooltip,
+  plotMarginTop,
+  plotMarginBottom,
  cleanView,
  presentationMode,
  selectedSeriesId,
@@ -308,6 +322,7 @@ const controlPanelModel = reactive({
  verticalGridColor,
  xAxisLineVisible,
  yAxisLineVisible,
+  ...xAxisLabelControlModel,
  frameBorderColor,
  frameBackgroundColor,
  frameBorderWidth,
@@ -354,6 +369,7 @@ const chartModel = reactive({
  cleanView,
  presentationMode,
  showTooltip,
+  plotMargin,
  zeroLine,
  frameWatermarkVisible,
  annotations,
--- a/src/DemoRouterApp.vue
+++ b/src/DemoRouterApp.vue
@@ -0,0 +1,14 @@
+<template>
+  <div class="demo-shell">
+    <header class="demo-shell__header">
+      <RouterLink class="demo-shell__brand" to="/">Waveform Analysis</RouterLink>
+      <nav class="demo-shell__nav" aria-label="示例导航">
+        <RouterLink to="/">综合示例</RouterLink>
+        <RouterLink to="/fixed-y-domain">固定振幅范围</RouterLink>
+      </nav>
+    </header>
+    <div class="demo-shell__content">
+      <RouterView />
+    </div>
+  </div>
+</template>
--- a/src/components/WaveformChart.vue
+++ b/src/components/WaveformChart.vue
@@ -23,6 +23,7 @@ const props = withDefaults(defineProps<WaveformChartProps>(), {
  interactionMode: undefined,
  grid: () => ({ rowCount: 2, columnCount: 1, showPagination: true }),
  rendering: () => ({}),
+  plotMargin: () => ({}),
  legend: () => ({ position: 'top-right', orientation: 'auto' }),
  defaultHiddenSeriesIds: () => [],
  cleanView: false,
--- a/src/components/WaveformChartView.vue
+++ b/src/components/WaveformChartView.vue
@@ -19,6 +19,7 @@ const {
  overlayMode,
  resolvedChartLeftMargin,
  titleAreaHeight,
+  resolvedPlotMargin,
  pointerInsideChart,
  handleNativeContextMenu,
  titleAreaReserved,
@@ -109,7 +110,7 @@ const {
      {
        'waveform-chart--clean': isCleanView,
        'waveform-chart--presentation': isPresentationMode,
-        'waveform-chart--panning': selection?.mode === 'pan',
+        'waveform-chart--panning': selection?.kind === 'pan',
      },
    ]"
    :style="containerStyle"
@@ -118,6 +119,8 @@ const {
    :data-presentation-mode="isPresentationMode"
    :data-overlay-mode="overlayMode"
    :data-chart-left-margin="resolvedChartLeftMargin"
+    :data-plot-margin-top="resolvedPlotMargin.top"
+    :data-plot-margin-bottom="resolvedPlotMargin.bottom"
    :data-title-area-height="titleAreaHeight"
    @pointerenter="pointerInsideChart = true"
    @pointerleave="pointerInsideChart = false"
@@ -244,7 +247,7 @@ const {
        />

        <rect
-          v-if="selectionBox && selection?.mode === 'box'"
+          v-if="selectionBox && selection?.kind === 'box'"
          class="waveform-chart__zoom-selection"
          :x="selectionBox.x"
          :y="selectionBox.y"
@@ -287,18 +290,18 @@ const {
            />
          </g>
        </g>
-
-        <text
-          v-if="resolvedXLabel && !isCleanView"
-          class="waveform-chart__label waveform-chart__x-label"
-          :x="innerWidth / 2"
-          :y="xAxisTitleY"
-          text-anchor="middle"
-        >
-          {{ resolvedXLabel }}
-        </text>
      </g>

+      <text
+        v-if="resolvedXLabel && !isCleanView"
+        class="waveform-chart__label waveform-chart__x-label"
+        :x="resolvedChartLeftMargin + innerWidth / 2"
+        :y="xAxisTitleY"
+        text-anchor="middle"
+      >
+        {{ resolvedXLabel }}
+      </text>
+
      <text
        v-if="hasChartArea && !hasWaveformData"
        class="waveform-chart__empty"
--- a/src/components/core/constants.ts
+++ b/src/components/core/constants.ts
@@ -7,6 +7,9 @@
 /** 图表边距 */
 export const margin = { top: 18, right: 24, bottom: 52, left: 64 }

+/** Distance from the drawing SVG bottom edge to the X-axis title baseline. */
+export const X_AXIS_TITLE_BOTTOM_OFFSET = 12
+
 /**
 * 图表最小高度（像素）
 */
--- a/src/components/core/fixedYDomainLayout.test.ts
+++ b/src/components/core/fixedYDomainLayout.test.ts
@@ -0,0 +1,116 @@
+import { zoomIdentity } from 'd3'
+import { describe, expect, it } from 'vitest'
+
+import { DEFAULT_WAVEFORM_RENDERING_OPTIONS } from '../../core'
+import type { DisplaySeries, DisplayTrack } from './types'
+import { buildTrackLayouts, resolveYAxisSeriesGroups } from './layout'
+
+function series(id: string, minimum: number, maximum: number): DisplaySeries {
+  return {
+    id,
+    name: id,
+    color: '#1677ff',
+    lineType: 'linear',
+    lineStyle: 'solid',
+    pointType: 'none',
+    errorBar: { visible: false, width: 1.5, capWidth: 8 },
+    points: [
+      { x: 0, y: minimum },
+      { x: 1, y: maximum },
+    ],
+    xDomain: [0, 1],
+    yDomain: [minimum, maximum],
+    hasErrorPoints: false,
+  }
+}
+
+function track(seriesList: DisplaySeries[]): DisplayTrack {
+  return {
+    id: 'track',
+    series: seriesList,
+    visibleSeries: seriesList,
+    xDomain: [0, 1],
+    yDomain: [0, 100],
+  }
+}
+
+describe('fixed Y-domain layout', () => {
+  it('uses an exact global fixed domain without applying nice bounds', () => {
+    const sourceTrack = track([series('a', 0, 100)])
+    const result = buildTrackLayouts({
+      cells: [
+        {
+          slotIndex: 0,
+          row: 0,
+          column: 0,
+          left: 0,
+          top: 0,
+          width: 120,
+          height: 100,
+          plotHeight: 100,
+          cellHeight: 130,
+          xAxisBand: 30,
+          series: sourceTrack,
+        },
+      ],
+      grid: { rowCount: 1, columnCount: 1, showPagination: false, trackLines: {} },
+      displayMode: 'independent',
+      overlayMode: 'single-axis',
+      independentTransforms: [zoomIdentity],
+      sharedZoomDomain: [0, 1],
+      fixedYDomain: [3, 97],
+      timeUnit: 'ms',
+      rendering: DEFAULT_WAVEFORM_RENDERING_OPTIONS,
+      hideSecondaryLabels: false,
+      yAxisLabelX: -50,
+      showCompactEmptyTracks: false,
+    })[0]
+
+    expect(result?.yScale.domain()).toEqual([3, 97])
+    expect(result?.yAxes[0]?.tickValues).toContain(3)
+    expect(result?.yAxes[0]?.tickValues).toContain(97)
+    expect(result?.seriesPaths[0]?.yScale.domain()).toEqual([3, 97])
+  })
+
+  it('resolves track, series, and global fixed-domain precedence', () => {
+    const sourceTrack = track([series('a', 0, 10), series('b', 20, 30)])
+
+    expect(
+      resolveYAxisSeriesGroups(sourceTrack, 'single-axis', [-5, 5], {
+        a: [-10, 10],
+        track: [300, 100],
+      })[0]?.domain,
+    ).toEqual([100, 300])
+
+    expect(
+      resolveYAxisSeriesGroups(sourceTrack, 'single-axis', [-5, 5], {
+        a: [-10, 10],
+      })[0]?.domain,
+    ).toEqual([-10, 10])
+  })
+
+  it('keeps per-series fixed domains on separate axes and merges axis overflow', () => {
+    const sourceTrack = track([
+      series('a', 0, 1),
+      series('b', 10, 11),
+      series('c', 20, 21),
+      series('d', 30, 31),
+      series('e', 40, 41),
+    ])
+    const groups = resolveYAxisSeriesGroups(sourceTrack, 'multi-axis', undefined, {
+      a: [-1, 1],
+      b: [-2, 2],
+      c: [-3, 3],
+      d: [-4, 4],
+      e: [-5, 5],
+    })
+
+    expect(groups.map((group) => group.domain)).toEqual([
+      [-1, 1],
+      [-2, 2],
+      [-3, 3],
+      [-5, 5],
+    ])
+    expect(groups.every((group) => group.fixed)).toBe(true)
+  })
+})
--- a/src/components/core/layout.test.ts
+++ b/src/components/core/layout.test.ts
@@ -192,7 +192,7 @@ describe('multi-value Y-axis grouping', () => {
    ])
  })

-  it('places left and right scientific exponents eight pixels outside their tick labels', () => {
+  it('reserves label clearance for exponent-prefixed ticks on both axis sides', () => {
    const layout = buildTrackLayouts({
      cells: [
        {
@@ -206,7 +206,7 @@ describe('multi-value Y-axis grouping', () => {
          plotHeight: 300,
          cellHeight: 330,
          xAxisBand: 30,
-          series: track([series('left', 0, 254), series('right', 0, 254)]),
+          series: track([series('left', 1000, 3000), series('right', 1000, 3000)]),
        },
      ],
      grid: { rowCount: 1, columnCount: 1, showPagination: false, trackLines: {} },
@@ -222,14 +222,13 @@ describe('multi-value Y-axis grouping', () => {
    })[0]

    expect(
-      layout?.yAxes.map(({ side, x, exponentX, exponentLabel }) => ({
+      layout?.yAxes.map(({ side, x, labelX }) => ({
        side,
-        offset: Math.abs(exponentX - x),
-        exponentLabel,
+        labelOffset: Math.abs(labelX - x),
      })),
    ).toEqual([
-      { side: 'left', offset: 43, exponentLabel: 'E+02' },
-      { side: 'right', offset: 43, exponentLabel: 'E+02' },
+      { side: 'left', labelOffset: 67 },
+      { side: 'right', labelOffset: 67 },
    ])
  })

@@ -237,7 +236,7 @@ describe('multi-value Y-axis grouping', () => {
    const [group] = buildYAxisSeriesGroups(track([series('long', -1e120, 1e120)]), 'multi-axis')

    expect(group).toBeDefined()
-    expect(measureYAxisGroupClearance(group!)).toBe(119)
+    expect(measureYAxisGroupClearance(group!)).toBe(90)
  })
 })

--- a/src/components/core/layout.ts
+++ b/src/components/core/layout.ts
@@ -1,12 +1,18 @@
 import { scaleLinear } from 'd3'

 import type { WaveformOverlayMode } from '../../types'
-import { formatScientificAxisExponent, formatScientificAxisLabel, paddedDomain } from '../../utils'
+import { formatScientificAxisLabel, paddedDomain } from '../../utils'
 import type { DisplaySeries, DisplayTrack, TrackLayout } from './types'
-import { MAX_MULTI_Y_AXIS_COUNT, Y_AXIS_EXPONENT_GAP } from './constants'
+import { MAX_MULTI_Y_AXIS_COUNT } from './constants'
+import {
+  mergeYDomains,
+  resolveSeriesFixedYDomain,
+  resolveTrackFixedYDomain,
+  type WaveformYDomain,
+} from './yDomain'

 // 导出常量供外部使用
-export { MAX_MULTI_Y_AXIS_COUNT, Y_AXIS_EXPONENT_GAP } from './constants'
+export { MAX_MULTI_Y_AXIS_COUNT } from './constants'

 const Y_AXIS_CHARACTER_WIDTH = 7
 const Y_AXIS_TICK_PADDING = 7
@@ -14,11 +20,12 @@ const Y_AXIS_OUTER_PADDING = 4
 const Y_AXIS_LABEL_GAP = 6
 const Y_AXIS_LABEL_BAND_WIDTH = 24

-interface YAxisSeriesGroup {
+export interface YAxisSeriesGroup {
  index: number
  side: 'left' | 'right'
  seriesList: DisplaySeries[]
  domain: [number, number]
+  fixed: boolean
 }

 function resolveAxisSides(axisCount: number): Array<'left' | 'right'> {
@@ -53,6 +60,7 @@ export function buildYAxisSeriesGroups(
    side: sides[index],
    seriesList: [] as DisplaySeries[],
    domain: [0, 1] as [number, number],
+    fixed: false,
  }))

  track.visibleSeries.forEach((series, index) => {
@@ -72,35 +80,49 @@ export function buildYAxisSeriesGroups(
  return grouped
 }

-export function axisTextMetrics(domain: [number, number]): {
-  exponentLabel: string | null
-  exponentWidth: number
-  tickTextWidth: number
-} {
-  const scale = scaleLinear(domain, [1, 0]).nice()
+export function resolveYAxisSeriesGroups(
+  track: DisplayTrack,
+  overlayMode: WaveformOverlayMode,
+  yDomain?: WaveformYDomain,
+  yDomains?: Record<string, WaveformYDomain>,
+): YAxisSeriesGroup[] {
+  const trackDomain = resolveTrackFixedYDomain(track, yDomains)
+  return buildYAxisSeriesGroups(track, overlayMode).map((group) => {
+    if (trackDomain) return { ...group, domain: trackDomain, fixed: true }
+    const seriesDomains = group.seriesList.map(
+      (series) => resolveSeriesFixedYDomain(series, yDomain, yDomains) ?? series.yDomain,
+    )
+    const fixed = group.seriesList.some((series) =>
+      resolveSeriesFixedYDomain(series, yDomain, yDomains),
+    )
+    return fixed ? { ...group, domain: mergeYDomains(seriesDomains), fixed } : group
+  })
+}
+
+export function axisTextMetrics(
+  domain: [number, number],
+  nice = true,
+  tickValues?: number[],
+): { tickTextWidth: number } {
+  const scale = scaleLinear(domain, [1, 0])
+  if (nice) scale.nice()
  const [axisMin, axisMax] = scale.domain()
-  const values = scale.ticks(10)
+  const values = tickValues ?? Array.from(new Set([axisMin, ...scale.ticks(10), axisMax]))
+  const topTickValue = Math.max(...values)
  const maximumTickCharacters = Math.max(
    1,
-    ...values.map((value) => formatScientificAxisLabel(value, { axisMin, axisMax }).length),
+    ...values.map(
+      (value) => formatScientificAxisLabel(value, { axisMin, axisMax, topTickValue }).length,
+    ),
  )
-  const exponentLabel = formatScientificAxisExponent(axisMin, axisMax)
  return {
-    exponentLabel,
-    exponentWidth: exponentLabel ? exponentLabel.length * Y_AXIS_CHARACTER_WIDTH : 0,
    tickTextWidth: maximumTickCharacters * Y_AXIS_CHARACTER_WIDTH,
  }
 }

-function axisExponentClearance(domain: [number, number]): number {
-  const { exponentLabel, exponentWidth } = axisTextMetrics(domain)
-  return exponentLabel ? exponentWidth + Y_AXIS_EXPONENT_GAP : 0
-}
-
 export function measureYAxisGroupClearance(group: YAxisSeriesGroup): number {
  return (
-    axisTextMetrics(group.domain).tickTextWidth +
-    axisExponentClearance(group.domain) +
+    axisTextMetrics(group.domain, !group.fixed).tickTextWidth +
    Y_AXIS_TICK_PADDING +
    Y_AXIS_LABEL_GAP +
    Y_AXIS_LABEL_BAND_WIDTH +
@@ -110,8 +132,7 @@ export function measureYAxisGroupClearance(group: YAxisSeriesGroup): number {

 function measureYAxisGroupTickClearance(group: YAxisSeriesGroup): number {
  return (
-    axisTextMetrics(group.domain).tickTextWidth +
-    axisExponentClearance(group.domain) +
+    axisTextMetrics(group.domain, !group.fixed).tickTextWidth +
    Y_AXIS_TICK_PADDING +
    Y_AXIS_OUTER_PADDING
  )
@@ -120,8 +141,10 @@ function measureYAxisGroupTickClearance(group: YAxisSeriesGroup): number {
 export function measureTrackYAxisClearance(
  track: DisplayTrack,
  overlayMode: WaveformOverlayMode,
+  yDomain?: WaveformYDomain,
+  yDomains?: Record<string, WaveformYDomain>,
 ): { left: number; right: number } {
-  return buildYAxisSeriesGroups(track, overlayMode).reduce(
+  return resolveYAxisSeriesGroups(track, overlayMode, yDomain, yDomains).reduce(
    (clearance, group) => {
      clearance[group.side] +=
        overlayMode === 'multi-axis' || track.visibleSeries.length === 1
--- a/src/components/core/trackLayoutBuilder.ts
+++ b/src/components/core/trackLayoutBuilder.ts
@@ -12,16 +12,20 @@ import {
  selectSeriesRenderPoints,
  type ResolvedWaveformRenderingOptions,
 } from '../../core/rendering'
-import type { WaveformDisplayMode, WaveformOverlayMode, WaveformPoint } from '../../types'
-import { buildMinorTicks, formatAxisTimeExponent, formatEndpointTime } from '../../utils'
+import type {
+  WaveformDisplayMode,
+  WaveformOverlayMode,
+  WaveformPoint,
+  WaveformXAxisLabelFormatter,
+} from '../../types'
+import { buildMinorTicks, formatXAxisLabel } from '../../utils'
 import {
  getBottomRowCellIndexes,
  type GridCellGeometry,
  type NormalizedWaveformGridOptions,
 } from './grid'
-import { axisTextMetrics, buildYAxisSeriesGroups } from './layout'
+import { axisTextMetrics, resolveYAxisSeriesGroups } from './layout'
 import type { DisplaySeries, DisplayTrack, TrackLayout, WaveformYAxisLayout } from './types'
-import { Y_AXIS_EXPONENT_GAP } from './constants'
 import {
  Y_AXIS_LABEL_BAND_WIDTH,
  Y_AXIS_LABEL_GAP,
@@ -42,8 +46,11 @@ export interface BuildTrackLayoutsOptions {
  sharedZoomDomain: [number, number]
  initialXDomain?: [number, number]
  initialXDomains?: Record<string, [number, number]>
+  fixedYDomain?: [number, number]
+  fixedYDomains?: Record<string, [number, number]>
  yDomains?: Record<string, [number, number]>
  timeUnit: 's' | 'ms'
+  xAxisLabelFormatter?: WaveformXAxisLabelFormatter
  rendering: ResolvedWaveformRenderingOptions
  hideSecondaryLabels: boolean
  yAxisLabelX: number
@@ -84,6 +91,7 @@ export function buildTrackLayouts(options: BuildTrackLayoutsOptions): TrackLayou
        ? scaleLinear(
            options.initialXDomains?.[displayTrack.id] ??
              options.initialXDomains?.[series.id] ??
+              options.initialXDomain ??
              displayTrack.xDomain,
            [0, cell.width],
          )
@@ -94,13 +102,18 @@ export function buildTrackLayouts(options: BuildTrackLayoutsOptions): TrackLayou
        : zoomIdentity
    const xScale = transform.rescaleX(baseXScale)
    const configuredYDomain = options.yDomains?.[displayTrack.id]
-    const yAxisGroups = buildYAxisSeriesGroups(displayTrack, options.overlayMode).map((group) => ({
-      ...group,
-      domain: configuredYDomain ?? group.domain,
-    }))
+    const yAxisGroups = resolveYAxisSeriesGroups(
+      displayTrack,
+      options.overlayMode,
+      options.fixedYDomain,
+      options.fixedYDomains,
+    ).map((group) =>
+      !group.fixed && configuredYDomain ? { ...group, domain: configuredYDomain } : group,
+    )
    const sideOffsets = { left: 0, right: 0 }
    const yAxes: WaveformYAxisLayout[] = yAxisGroups.map((group) => {
-      const scale = scaleLinear(group.domain, [cell.plotHeight, 0]).nice()
+      const scale = scaleLinear(group.domain, [cell.plotHeight, 0])
+      if (!group.fixed) scale.nice()
      const majorTicks = scale.ticks(Math.max(2, Math.floor(cell.plotHeight / 55)))
      const [axisStart, axisEnd] = scale.domain()
      const showAxisEnd = options.displayMode !== 'compact' || cell.row === 0
@@ -110,28 +123,16 @@ export function buildTrackLayouts(options: BuildTrackLayoutsOptions): TrackLayou
      const tickValues = Array.from(
        new Set([axisStart, ...visibleMajorTicks, ...(showAxisEnd ? [axisEnd] : [])]),
      )
-      const { exponentLabel, exponentWidth, tickTextWidth } = axisTextMetrics(group.domain)
-      const exponentClearance = exponentLabel ? exponentWidth + Y_AXIS_EXPONENT_GAP : 0
+      const { tickTextWidth } = axisTextMetrics(group.domain, !group.fixed, tickValues)
      const clearance =
        tickTextWidth +
        Y_AXIS_TICK_PADDING +
-        exponentClearance +
        Y_AXIS_LABEL_GAP +
        Y_AXIS_LABEL_BAND_WIDTH +
        Y_AXIS_OUTER_PADDING
      const x = group.side === 'left' ? -sideOffsets.left : cell.width + sideOffsets.right
-      const exponentX =
-        x +
-        (group.side === 'left'
-          ? -(Y_AXIS_TICK_PADDING + tickTextWidth + Y_AXIS_EXPONENT_GAP)
-          : Y_AXIS_TICK_PADDING + tickTextWidth + Y_AXIS_EXPONENT_GAP)
      const labelDistance =
-        tickTextWidth +
-        Y_AXIS_TICK_PADDING +
-        exponentClearance +
-        exponentWidth +
-        Y_AXIS_LABEL_GAP +
-        Y_AXIS_LABEL_BAND_WIDTH / 2
+        tickTextWidth + Y_AXIS_TICK_PADDING + Y_AXIS_LABEL_GAP + Y_AXIS_LABEL_BAND_WIDTH / 2
      const labelX = x + (group.side === 'left' ? -labelDistance : labelDistance)
      sideOffsets[group.side] += clearance
      return {
@@ -139,8 +140,6 @@ export function buildTrackLayouts(options: BuildTrackLayoutsOptions): TrackLayou
        side: group.side,
        x,
        labelX,
-        exponentX,
-        exponentLabel,
        scale,
        majorTicks,
        minorTicks: buildMinorTicks(majorTicks),
@@ -154,10 +153,21 @@ export function buildTrackLayouts(options: BuildTrackLayoutsOptions): TrackLayou
    const yAxisTickValues = yAxes[0]?.tickValues ?? []
    const domain = xScale.domain() as [number, number]
    const endpointLabels = {
-      start: formatEndpointTime(domain[0], domain, options.timeUnit),
-      end: formatEndpointTime(domain[1], domain, options.timeUnit),
+      start: formatXAxisLabel(
+        domain[0],
+        domain,
+        options.timeUnit,
+        'start',
+        options.xAxisLabelFormatter,
+      ),
+      end: formatXAxisLabel(
+        domain[1],
+        domain,
+        options.timeUnit,
+        'end',
+        options.xAxisLabelFormatter,
+      ),
    }
-    const xAxisExponent = formatAxisTimeExponent(domain, options.timeUnit)
    const leftClearance = endpointLabels.start.length * 7 + 10
    const rightClearance = endpointLabels.end.length * 7 + 10
    const xAxisTickValues = xMajorTicks.filter((tick) => {
@@ -224,7 +234,6 @@ export function buildTrackLayouts(options: BuildTrackLayoutsOptions): TrackLayou
      yAxisTickValues,
      xAxisTickValues,
      endpointLabels,
-      xAxisExponent,
      path: seriesPaths[0]?.path ?? null,
      seriesPaths,
      gridLines: options.grid.trackLines[displayTrack.id] ?? {
--- a/src/components/core/types.ts
+++ b/src/components/core/types.ts
@@ -51,8 +51,6 @@ export interface WaveformYAxisLayout {
  side: 'left' | 'right'
  x: number
  labelX: number
-  exponentX: number
-  exponentLabel: string | null
  scale: ScaleLinear<number, number>
  majorTicks: number[]
  minorTicks: number[]
@@ -109,7 +107,6 @@ export interface TrackLayout {
  yAxisTickValues: number[]
  xAxisTickValues: number[]
  endpointLabels: { start: string; end: string }
-  xAxisExponent: string | null
  path: string | null
  seriesPaths: TrackSeriesPath[]
  showXAxis: boolean
--- a/src/components/core/useWaveformChartController.ts
+++ b/src/components/core/useWaveformChartController.ts
@@ -6,6 +6,7 @@ import {
  shallowReactive,
  shallowRef,
  toRefs,
+  watch,
  watchEffect,
  type ComponentPublicInstance,
  type Ref,
@@ -17,6 +18,7 @@ import { useWaveformChartAnnotations } from '../annotation/useWaveformChartAnnot
 import { useWaveformHover } from '../interaction/useWaveformHover'
 import { useWaveformViewport } from '../interaction/useWaveformViewport'
 import { useWaveformZoom } from '../interaction/useWaveformZoom'
+import { ViewportInteractionStateMachine } from '../interaction/viewportInteractionState'
 import { useAnimationFrameThrottle } from '../utils/useAnimationFrameThrottle'
 import { margin } from './constants'
 import { getPageSize } from './grid'
@@ -68,7 +70,17 @@ export function useWaveformChartController(
  const annotationInteraction = useWaveformAnnotationInteraction()
  const editorSeriesOptions = ref<AnnotationSeriesCandidate[]>([])
  const hoverThrottle = useAnimationFrameThrottle()
-  const selection = ref<ViewportSelectionState | null>(null)
+
+  watch(
+    [() => props.yDomain, () => props.yDomains],
+    () => {
+      sharedYDomains.value = {}
+      independentYDomains.value = {}
+    },
+    { deep: true },
+  )
+  const selection = shallowRef<ViewportSelectionState | null>(null)
+  const viewportInteraction = shallowRef(markRaw(new ViewportInteractionStateMachine()))
  const spacePressed = ref(false)
  const pointerInsideChart = ref(false)
  let handleDataReferenceChange: () => void = () => undefined
@@ -183,6 +195,7 @@ export function useWaveformChartController(
    props,
    emit,
    selection,
+    viewportInteraction,
    spacePressed,
    trackLayouts,
    chartTracks,
--- a/src/components/core/useWaveformLayout.ts
+++ b/src/components/core/useWaveformLayout.ts
@@ -2,7 +2,7 @@ import { scaleLinear, type ZoomTransform } from 'd3'
 import { computed, type ComputedRef, type Ref, type ShallowRef } from 'vue'

 import { resolveWaveformRenderingOptions } from '../../core'
-import { formatScientificAxisExponent, formatScientificAxisLabel, paddedDomain } from '../../utils'
+import { paddedDomain } from '../../utils'
 import {
  layoutAnnotations,
  type AnnotationSeriesInfo,
@@ -24,9 +24,13 @@ import {
  normalizeGridOptions,
  paginateSeries,
  resolveGridCellGeometry,
-  X_AXIS_BAND,
 } from './grid'
-import { buildTrackLayouts, measureTrackYAxisClearance, Y_AXIS_EXPONENT_GAP } from './layout'
+import {
+  buildTrackLayouts,
+  axisTextMetrics,
+  measureTrackYAxisClearance,
+  resolveYAxisSeriesGroups,
+} from './layout'
 import type { DisplaySeries, DisplayTrack, TrackLayout } from './types'
 import type { PreparedWaveformSeries } from './useWaveformData'
 import type { ResolvedWaveformChartProps } from './waveformChartTypes'
@@ -104,39 +108,21 @@ export function useWaveformLayout(context: LayoutContext) {
  const yAxisMetrics = computed(() => {
    const axisText = chartTracks.value
      .filter((track) => track.visibleSeries.length > 0)
-      .map((track) => {
-        const scale = scaleLinear(track.yDomain, [1, 0]).nice()
-        const [axisMin, axisMax] = scale.domain()
-        return {
-          exponentLabel: formatScientificAxisExponent(axisMin, axisMax),
-          tickLabels: scale
-            .ticks(10)
-            .map((value) => formatScientificAxisLabel(value, { axisMin, axisMax })),
-        }
-      })
-    const maximumCharacters = Math.max(
-      1,
-      ...axisText.flatMap(({ tickLabels }) => tickLabels).map((label) => label.length),
-    )
-    const tickTextWidth = maximumCharacters * Y_AXIS_CHARACTER_WIDTH
-    const maximumExponentWidth = Math.max(
-      0,
-      ...axisText.map(({ exponentLabel }) => (exponentLabel?.length ?? 0) * Y_AXIS_CHARACTER_WIDTH),
-    )
-    const exponentClearance = maximumExponentWidth ? maximumExponentWidth + Y_AXIS_EXPONENT_GAP : 0
-    const tickClearance =
-      tickTextWidth + Y_AXIS_TICK_PADDING + exponentClearance + Y_AXIS_OUTER_PADDING
+      .flatMap((track) =>
+        resolveYAxisSeriesGroups(track, props.overlayMode, props.yDomain, props.yDomains),
+      )
+      .map((group) => axisTextMetrics(group.domain, !group.fixed).tickTextWidth)
+    const tickTextWidth = Math.max(Y_AXIS_CHARACTER_WIDTH, ...axisText)
+    const tickClearance = tickTextWidth + Y_AXIS_TICK_PADDING + Y_AXIS_OUTER_PADDING
    const labelCenterX = -(
      Y_AXIS_TICK_PADDING +
      tickTextWidth +
-      exponentClearance +
      Y_AXIS_LABEL_GAP +
      Y_AXIS_LABEL_BAND_WIDTH / 2
    )
    const fullClearance =
      tickTextWidth +
      Y_AXIS_TICK_PADDING +
-      exponentClearance +
      Y_AXIS_LABEL_GAP +
      Y_AXIS_LABEL_BAND_WIDTH +
      Y_AXIS_OUTER_PADDING
@@ -165,7 +151,12 @@ export function useWaveformLayout(context: LayoutContext) {
  const multiAxisClearance = computed(() =>
    chartTracks.value.reduce(
      (maximum, track) => {
-        const clearance = measureTrackYAxisClearance(track, props.overlayMode)
+        const clearance = measureTrackYAxisClearance(
+          track,
+          props.overlayMode,
+          props.yDomain,
+          props.yDomains,
+        )
        return {
          left: Math.max(maximum.left, clearance.left),
          right: Math.max(maximum.right, clearance.right),
@@ -281,6 +272,8 @@ export function useWaveformLayout(context: LayoutContext) {
      sharedZoomDomain: sharedZoomDomain.value,
      initialXDomain: props.initialXDomain ? initialXDomain.value : undefined,
      initialXDomains: props.initialXDomains,
+      fixedYDomain: props.yDomain,
+      fixedYDomains: props.yDomains,
      yDomains:
        props.displayMode === 'independent'
          ? Object.fromEntries(
@@ -291,6 +284,7 @@ export function useWaveformLayout(context: LayoutContext) {
            )
          : sharedYDomains.value,
      timeUnit: props.timeUnit,
+      xAxisLabelFormatter: props.axes?.x?.labelFormatter,
      rendering: renderingOptions.value,
      hideSecondaryLabels: isCleanView.value || yAxisLayout.value.hideSecondaryLabels,
      yAxisLabelX: yAxisMetrics.value.labelCenterX,
@@ -321,7 +315,6 @@ export function useWaveformLayout(context: LayoutContext) {
        )
      : [],
  )
-  const xAxisTitleY = computed(() => innerHeight.value + X_AXIS_BAND + 10)
  const editorSeries = computed<AnnotationSeriesInfo | undefined>(() => {
    const seriesId = annotationInteraction.editorDraft.value?.annotation.seriesId
    const series = chartSeries.value.find((item) => item.id === seriesId)
@@ -365,7 +358,6 @@ export function useWaveformLayout(context: LayoutContext) {
    resolveSeriesYScale,
    annotationTrackLayouts,
    renderedAnnotations,
-    xAxisTitleY,
    editorSeries,
    resolveFrameNumber,
  }
--- a/src/components/core/useWaveformPresentation.ts
+++ b/src/components/core/useWaveformPresentation.ts
@@ -7,6 +7,7 @@ import {
  TITLE_CHAR_WIDTH_RATIO,
  TITLE_DEFAULT_FONT_SIZE,
  TITLE_LINE_HEIGHT,
+  X_AXIS_TITLE_BOTTOM_OFFSET,
  ZERO_LINE_DEFAULTS,
 } from './constants'
 import { calculateRotatedTitleLayout, TITLE_AREA_HORIZONTAL_PADDING } from './title'
@@ -144,11 +145,23 @@ export function useWaveformPresentation(context: PresentationContext) {
  const titleAreaHeight = computed(() =>
    titleAreaReserved.value ? titleLayout.value.areaHeight : 0,
  )
-  const chartTopMargin = computed(() => margin.top)
+  const resolvePlotMargin = (value: number | undefined, fallback: number) =>
+    typeof value === 'number' && Number.isFinite(value) && value >= 0 ? value : fallback
+  const resolvedPlotMargin = computed(() => ({
+    top: resolvePlotMargin(props.plotMargin.top, margin.top),
+    bottom: resolvePlotMargin(props.plotMargin.bottom, margin.bottom),
+  }))
+  const chartTopMargin = computed(() => resolvedPlotMargin.value.top)
  const drawingHeight = computed(() =>
    Math.max(0, chartHeight.value - titleAreaHeight.value - paginationBandHeight.value),
  )
-  const innerHeight = computed(() => Math.max(0, drawingHeight.value - margin.top - margin.bottom))
+  const xAxisTitleY = computed(() => Math.max(0, drawingHeight.value - X_AXIS_TITLE_BOTTOM_OFFSET))
+  const innerHeight = computed(() =>
+    Math.max(
+      0,
+      drawingHeight.value - resolvedPlotMargin.value.top - resolvedPlotMargin.value.bottom,
+    ),
+  )
  const titleAreaStyle = computed<CSSProperties>(() => ({
    height: `${titleAreaHeight.value}px`,
    justifyContent:
@@ -193,8 +206,10 @@ export function useWaveformPresentation(context: PresentationContext) {
    titleMeasureStyle,
    titleLayout,
    titleAreaHeight,
+    resolvedPlotMargin,
    chartTopMargin,
    drawingHeight,
+    xAxisTitleY,
    innerHeight,
    titleAreaStyle,
    titleVisualStyle,
--- a/src/components/core/waveformChartTypes.ts
+++ b/src/components/core/waveformChartTypes.ts
@@ -7,6 +7,7 @@ import type {
  WaveformInteractionMode,
  WaveformLegendOptions,
  WaveformOverlayMode,
+  WaveformPlotMargin,
  WaveformPoint,
  WaveformRenderingOptions,
  WaveformTitleOptions,
@@ -31,6 +32,8 @@ export interface WaveformChartProps {
  minVisiblePoints?: number
  initialXDomain?: [number, number]
  initialXDomains?: Record<string, [number, number]>
+  yDomain?: [number, number]
+  yDomains?: Record<string, [number, number]>
  timeUnit?: 's' | 'ms'
  frameNumber?: string | number
  frameStyle?: WaveformFrameStyle
@@ -40,6 +43,7 @@ export interface WaveformChartProps {
  interactionMode?: WaveformInteractionMode
  grid?: WaveformGridOptions
  rendering?: WaveformRenderingOptions
+  plotMargin?: WaveformPlotMargin
  title?: WaveformTitleOptions
  legend?: WaveformLegendOptions
  hiddenSeriesIds?: string[]
@@ -63,6 +67,7 @@ type DefaultedProp =
  | 'annotationsVisible'
  | 'grid'
  | 'rendering'
+  | 'plotMargin'
  | 'legend'
  | 'defaultHiddenSeriesIds'
  | 'cleanView'
@@ -90,16 +95,17 @@ export interface WaveformChartEmit {
  (event: 'page-change', page: number, pageCount: number): void
 }

-export interface ViewportSelectionState {
+interface ViewportSelectionBase {
  trackIndex: number
  independent: boolean
-  overlay: SVGRectElement
  startX: number
  startY: number
  currentX: number
  currentY: number
  pointerId: number
-  mode: 'box' | 'pan'
  xDomain: [number, number]
  yDomains: Record<string, [number, number]>
 }
+
+export type ViewportSelectionState =
+  (ViewportSelectionBase & { kind: 'box' }) | (ViewportSelectionBase & { kind: 'pan' })
--- a/src/components/core/yDomain.test.ts
+++ b/src/components/core/yDomain.test.ts
@@ -0,0 +1,56 @@
+import { describe, expect, it } from 'vitest'
+
+import type { DisplayTrack } from './types'
+import { hasFixedYDomainForTrack, mergeYDomains, normalizeYDomain } from './yDomain'
+
+const track: DisplayTrack = {
+  id: 'shared-track',
+  series: [],
+  visibleSeries: [
+    {
+      id: 'channel-a',
+      name: 'A',
+      color: '#1677ff',
+      lineType: 'linear',
+      lineStyle: 'solid',
+      pointType: 'none',
+      errorBar: { visible: false, width: 1.5, capWidth: 8 },
+      points: [],
+      xDomain: [0, 1],
+      yDomain: [0, 1],
+      hasErrorPoints: false,
+    },
+  ],
+  xDomain: [0, 1],
+  yDomain: [0, 1],
+}
+
+describe('fixed Y domains', () => {
+  it('normalizes valid reversed domains', () => {
+    expect(normalizeYDomain([97, 3])).toEqual([3, 97])
+    expect(normalizeYDomain([-10, 10])).toEqual([-10, 10])
+  })
+
+  it.each([undefined, [1, 1], [Number.NaN, 1], [0, Number.POSITIVE_INFINITY]])(
+    'rejects an invalid domain: %j',
+    (domain) => {
+      expect(normalizeYDomain(domain as [number, number] | undefined)).toBeUndefined()
+    },
+  )
+
+  it('detects valid track, series, and global configuration only', () => {
+    expect(hasFixedYDomainForTrack(track, [-1, 1])).toBe(true)
+    expect(hasFixedYDomainForTrack(track, undefined, { 'shared-track': [-2, 2] })).toBe(true)
+    expect(hasFixedYDomainForTrack(track, undefined, { 'channel-a': [-3, 3] })).toBe(true)
+    expect(hasFixedYDomainForTrack(track, [0, 0], { 'channel-a': [1, 1] })).toBe(false)
+  })
+
+  it('merges configured and automatic series domains without padding', () => {
+    expect(
+      mergeYDomains([
+        [3, 97],
+        [-20, 40],
+      ]),
+    ).toEqual([-20, 97])
+  })
+})
--- a/src/components/core/yDomain.ts
+++ b/src/components/core/yDomain.ts
@@ -0,0 +1,50 @@
+import type { DisplaySeries, DisplayTrack } from './types'
+
+export type WaveformYDomain = [number, number]
+
+export function normalizeYDomain(
+  domain: readonly [number, number] | undefined,
+): WaveformYDomain | undefined {
+  if (
+    !domain ||
+    !Number.isFinite(domain[0]) ||
+    !Number.isFinite(domain[1]) ||
+    domain[0] === domain[1]
+  ) {
+    return undefined
+  }
+  return domain[0] < domain[1] ? [domain[0], domain[1]] : [domain[1], domain[0]]
+}
+
+export function resolveTrackFixedYDomain(
+  track: Pick<DisplayTrack, 'id'>,
+  yDomains?: Record<string, WaveformYDomain>,
+): WaveformYDomain | undefined {
+  return normalizeYDomain(yDomains?.[track.id])
+}
+
+export function resolveSeriesFixedYDomain(
+  series: Pick<DisplaySeries, 'id'>,
+  yDomain?: WaveformYDomain,
+  yDomains?: Record<string, WaveformYDomain>,
+): WaveformYDomain | undefined {
+  return normalizeYDomain(yDomains?.[series.id]) ?? normalizeYDomain(yDomain)
+}
+
+export function hasFixedYDomainForTrack(
+  track: Pick<DisplayTrack, 'id' | 'visibleSeries'>,
+  yDomain?: WaveformYDomain,
+  yDomains?: Record<string, WaveformYDomain>,
+): boolean {
+  return Boolean(
+    resolveTrackFixedYDomain(track, yDomains) ||
+    track.visibleSeries.some((series) => resolveSeriesFixedYDomain(series, yDomain, yDomains)),
+  )
+}
+
+export function mergeYDomains(domains: readonly WaveformYDomain[]): WaveformYDomain {
+  return [
+    Math.min(...domains.map((domain) => domain[0])),
+    Math.max(...domains.map((domain) => domain[1])),
+  ]
+}
--- a/src/components/data/types.ts
+++ b/src/components/data/types.ts
@@ -13,6 +13,7 @@ export type {
  WaveformAnnotationStyle,
  WaveformAnnotation,
  WaveformRenderingOptions,
+  WaveformPlotMargin,
  WaveformTitleTextStyle,
  WaveformTitleOptions,
  WaveformLegendPosition,
--- a/src/components/index.ts
+++ b/src/components/index.ts
@@ -11,6 +11,7 @@ export type {
  WaveformAnnotationStyle,
  WaveformAnnotation,
  WaveformRenderingOptions,
+  WaveformPlotMargin,
  WaveformTitleTextStyle,
  WaveformTitleOptions,
  WaveformLegendPosition,
--- a/src/components/interaction/WaveformTooltip.test.ts
+++ b/src/components/interaction/WaveformTooltip.test.ts
@@ -91,6 +91,22 @@ describe('WaveformTooltip', () => {
    expect(wrapper.get('.waveform-tooltip__value').text()).toBe('-1,405.4932 A')
  })

+  it('formats tooltip time with at most four decimal places', () => {
+    const wrapper = mount(WaveformTooltip, {
+      props: {
+        visible: true,
+        position: { x: 10, y: 10 },
+        timeUnit: 's',
+        hoveredPoint: { x: 1.234567, y: 12 },
+        seriesPoints: [],
+        containerWidth: 400,
+        containerHeight: 300,
+      },
+    })
+
+    expect(wrapper.get('.waveform-tooltip__time').text()).toBe('s: 1.2346')
+  })
+
  it('omits the error label when both resolved errors are zero', () => {
    const point = { x: 1, y: 12 }
    const wrapper = mount(WaveformTooltip, {
--- a/src/components/interaction/useWaveformHover.ts
+++ b/src/components/interaction/useWaveformHover.ts
@@ -136,7 +136,7 @@ export function useWaveformHover(context: HoverContext) {
  }
  const handleSharedPointerMove = (event: PointerEvent) => {
    if (isPresentationMode.value) return
-    if (selection.value?.overlay === event.currentTarget) {
+    if (selection.value && !selection.value.independent) {
      updateViewportDrag(event)
      return
    }
--- a/src/components/interaction/useWaveformViewport.ts
+++ b/src/components/interaction/useWaveformViewport.ts
@@ -1,19 +1,22 @@
 import { pointer, scaleLinear, zoomIdentity, type ZoomTransform } from 'd3'
-import { computed, nextTick, type ComputedRef, type Ref, type ShallowRef } from 'vue'
+import { computed, nextTick, shallowRef, type ComputedRef, type Ref, type ShallowRef } from 'vue'

 import { MINIMUM_SELECTION_SIZE } from '../core/constants'
 import type { DisplayTrack, TrackLayout } from '../core/types'
+import { hasFixedYDomainForTrack } from '../core/yDomain'
 import type {
  ResolvedWaveformChartProps,
  ViewportSelectionState,
  WaveformChartEmit,
 } from '../core/waveformChartTypes'
 import type { AnnotationSeriesCandidate } from '../annotation'
+import type { ViewportInteractionStateMachine } from './viewportInteractionState'

 interface ViewportContext {
  props: ResolvedWaveformChartProps
  emit: WaveformChartEmit
  selection: Ref<ViewportSelectionState | null>
+  viewportInteraction: ShallowRef<ViewportInteractionStateMachine>
  spacePressed: Ref<boolean>
  trackLayouts: ComputedRef<TrackLayout[]>
  chartTracks: ComputedRef<DisplayTrack[]>
@@ -42,6 +45,7 @@ export function useWaveformViewport(context: ViewportContext) {
    props,
    emit,
    selection,
+    viewportInteraction,
    spacePressed,
    trackLayouts,
    chartTracks,
@@ -64,6 +68,10 @@ export function useWaveformViewport(context: ViewportContext) {
    clearHover,
    resolveTrackAtPointer,
  } = context
+  const activeOverlay = shallowRef<SVGRectElement>()
+  const syncSelection = () => {
+    selection.value = viewportInteraction.value.state
+  }
  const selectionBox = computed(() => {
    const active = selection.value
    if (!active) return null
@@ -142,19 +150,19 @@ export function useWaveformViewport(context: ViewportContext) {
    const [rawX, rawY] = pointer(event, overlay)
    const x = Math.max(0, Math.min(independent ? track.width : innerWidth.value, rawX))
    const y = Math.max(0, Math.min(independent ? track.height : innerHeight.value, rawY))
-    selection.value = {
+    const started = viewportInteraction.value.begin({
      trackIndex,
      independent,
-      overlay,
      startX: x,
      startY: y,
-      currentX: x,
-      currentY: y,
      pointerId: event.pointerId,
-      mode: panRequested ? 'pan' : 'box',
+      kind: panRequested ? 'pan' : 'box',
      xDomain: track.xScale.domain() as [number, number],
      yDomains: currentYDomains(),
-    }
+    })
+    if (!started) return
+    activeOverlay.value = overlay
+    syncSelection()
    overlay.setPointerCapture?.(event.pointerId)
    clearHover()
    event.preventDefault()
@@ -190,9 +198,13 @@ export function useWaveformViewport(context: ViewportContext) {
    const nextIndependentDomains = { ...independentYDomains.value }
    const nextSharedDomains = { ...sharedYDomains.value }
    targets.forEach((target) => {
+      const chartTrack = chartTracks.value.find((item) => item.id === target.id)
+      if (chartTrack && hasFixedYDomainForTrack(chartTrack, props.yDomain, props.yDomains)) {
+        return
+      }
      const key = target.series.trackId ?? target.series.id
      const source = active.yDomains[key] ?? (target.yScale.domain() as [number, number])
-      const boundary = chartTracks.value.find((item) => item.id === key)?.yDomain ?? source
+      const boundary = chartTrack?.yDomain ?? source
      const ySpan = source[1] - source[0]
      const nextY = clampDomain(
        [source[0] + (dy / height) * ySpan, source[1] + (dy / height) * ySpan],
@@ -208,27 +220,33 @@ export function useWaveformViewport(context: ViewportContext) {
  const updateViewportDrag = (event: PointerEvent) => {
    if (isPresentationMode.value) return
    const active = selection.value
-    if (!active || event.pointerId !== active.pointerId) return
+    const overlay = activeOverlay.value
+    if (!active || !overlay || event.pointerId !== active.pointerId) return
    const track = trackLayouts.value.find((item) => item.index === active.trackIndex)
    if (!track) return
-    const [rawX, rawY] = pointer(event, active.overlay)
-    active.currentX = Math.max(
+    const [rawX, rawY] = pointer(event, overlay)
+    const currentX = Math.max(
      0,
      Math.min(active.independent ? track.width : innerWidth.value, rawX),
    )
-    active.currentY = Math.max(
+    const currentY = Math.max(
      0,
      Math.min(active.independent ? track.height : innerHeight.value, rawY),
    )
-    selection.value = { ...active }
-    if (active.mode === 'pan') applyPan(active, track)
+    const next = viewportInteraction.value.move(event.pointerId, { currentX, currentY })
+    if (!next) return
+    selection.value = next
+    if (next.kind === 'pan') applyPan(next, track)
    event.preventDefault()
  }
  const cancelViewportDrag = (event?: PointerEvent) => {
    const active = selection.value
    if (!active || (event && event.pointerId !== active.pointerId)) return
-    active.overlay.releasePointerCapture?.(active.pointerId)
-    selection.value = null
+    activeOverlay.value?.releasePointerCapture?.(active.pointerId)
+    if (viewportInteraction.value.cancel(event?.pointerId)) {
+      activeOverlay.value = undefined
+      syncSelection()
+    }
  }
  const applyBoxZoom = (active: ViewportSelectionState) => {
    const track = trackLayouts.value.find((item) => item.index === active.trackIndex)
@@ -295,15 +313,32 @@ export function useWaveformViewport(context: ViewportContext) {
    }
    const active = selection.value
    if (!active || event.pointerId !== active.pointerId) return
-    updateViewportDrag(event)
-    active.overlay.releasePointerCapture?.(active.pointerId)
-    selection.value = null
-    if (active.mode === 'pan') {
+    const track = trackLayouts.value.find((item) => item.index === active.trackIndex)
+    if (!track) return
+    const overlay = activeOverlay.value
+    if (!overlay) return
+    const [rawX, rawY] = pointer(event, overlay)
+    const currentX = Math.max(
+      0,
+      Math.min(active.independent ? track.width : innerWidth.value, rawX),
+    )
+    const currentY = Math.max(
+      0,
+      Math.min(active.independent ? track.height : innerHeight.value, rawY),
+    )
+    const completed = viewportInteraction.value.finish(event.pointerId, { currentX, currentY })
+    if (!completed) return
+    overlay.releasePointerCapture?.(completed.pointerId)
+    activeOverlay.value = undefined
+    syncSelection()
+    event.preventDefault()
+    if (completed.kind === 'pan') {
+      applyPan(completed, track)
      void nextTick(configureZoom)
      return
    }
-    if (Math.abs(active.currentX - active.startX) >= MINIMUM_SELECTION_SIZE) {
-      applyBoxZoom(active)
+    if (Math.abs(completed.currentX - completed.startX) >= MINIMUM_SELECTION_SIZE) {
+      applyBoxZoom(completed)
    }
  }
  const resetViewport = (trackIndex?: number) => {
--- a/src/components/interaction/useWaveformZoom.ts
+++ b/src/components/interaction/useWaveformZoom.ts
@@ -3,6 +3,7 @@ import {
  select,
  zoom,
  zoomIdentity,
+  zoomTransform,
  type D3ZoomEvent,
  type ZoomBehavior,
  type ZoomTransform,
@@ -237,6 +238,15 @@ export function useWaveformZoom(context: ZoomContext) {
    const tracks = trackLayouts.value.filter((track) => track.hasVisibleSeries)
    return tracks.length > 0 && tracks.every(canZoomTrack)
  }
+  const canHandleWheelZoom = (event: Event, canZoomIn: boolean): boolean => {
+    if (event.type !== 'wheel') return false
+    const deltaY = (event as WheelEvent).deltaY
+    if (deltaY < 0) return canZoomIn
+    if (deltaY > 0) {
+      return zoomTransform(event.currentTarget as Element).k > ZOOM_CONSTRAINTS.MIN_SCALE
+    }
+    return false
+  }
  const configureZoom = () => {
    clearZoomBindings()
    if (
@@ -256,10 +266,7 @@ export function useWaveformZoom(context: ZoomContext) {
        if (!overlay) return
        const dataDomain = resolveInitialTrackDomain(track)
        const behavior = zoom<SVGRectElement, unknown>()
-          .filter(
-            (event) =>
-              event.type === 'wheel' && (event as WheelEvent).deltaY < 0 && canZoomTrack(track),
-          )
+          .filter((event) => canHandleWheelZoom(event, canZoomTrack(track)))
          .scaleExtent([1, resolveMaximumZoomScale(dataDomain)])
          .extent([
            [0, 0],
@@ -287,10 +294,7 @@ export function useWaveformZoom(context: ZoomContext) {
    const overlay = sharedOverlayElement.value
    if (!overlay) return
    const behavior = zoom<SVGRectElement, unknown>()
-      .filter(
-        (event) =>
-          event.type === 'wheel' && (event as WheelEvent).deltaY < 0 && canZoomSharedTracks(),
-      )
+      .filter((event) => canHandleWheelZoom(event, canZoomSharedTracks()))
      .scaleExtent([1, resolveMaximumZoomScale(initialXDomain.value)])
      .extent([
        [0, 0],
--- a/src/components/interaction/viewportInteractionState.test.ts
+++ b/src/components/interaction/viewportInteractionState.test.ts
@@ -0,0 +1,76 @@
+import { describe, expect, it } from 'vitest'
+
+import { ViewportInteractionStateMachine } from './viewportInteractionState'
+
+const gesture = {
+  trackIndex: 2,
+  independent: true,
+  startX: 10,
+  startY: 20,
+  pointerId: 7,
+  kind: 'box' as const,
+  xDomain: [0, 100] as [number, number],
+  yDomains: { track: [-1, 1] as [number, number] },
+}
+
+describe('ViewportInteractionStateMachine', () => {
+  it('accepts one gesture and rejects a conflicting start', () => {
+    const machine = new ViewportInteractionStateMachine()
+
+    expect(machine.begin(gesture)).toBe(true)
+    expect(machine.begin({ ...gesture, pointerId: 8 })).toBe(false)
+    expect(machine.state).toMatchObject({ kind: 'box', pointerId: 7 })
+  })
+
+  it('rejects moves and completion from a different pointer', () => {
+    const machine = new ViewportInteractionStateMachine()
+    machine.begin(gesture)
+
+    expect(machine.move(8, { currentX: 30, currentY: 40 })).toBeNull()
+    expect(machine.finish(8, { currentX: 30, currentY: 40 })).toBeNull()
+    expect(machine.state?.currentX).toBe(10)
+  })
+
+  it('updates a valid pointer, completes it, and returns to idle', () => {
+    const machine = new ViewportInteractionStateMachine()
+    machine.begin({ ...gesture, kind: 'pan' })
+
+    expect(machine.move(7, { currentX: 30, currentY: 40 })).toMatchObject({
+      kind: 'pan',
+      currentX: 30,
+      currentY: 40,
+    })
+    expect(machine.finish(7, { currentX: 50, currentY: 60 })).toMatchObject({
+      kind: 'pan',
+      currentX: 50,
+      currentY: 60,
+    })
+    expect(machine.state).toBeNull()
+  })
+
+  it('only cancels the owning pointer and supports explicit reset', () => {
+    const machine = new ViewportInteractionStateMachine()
+    machine.begin(gesture)
+
+    expect(machine.cancel(8)).toBe(false)
+    expect(machine.state).not.toBeNull()
+    expect(machine.cancel(7)).toBe(true)
+    expect(machine.state).toBeNull()
+
+    machine.begin(gesture)
+    machine.reset()
+    expect(machine.state).toBeNull()
+  })
+
+  it('returns defensive copies from its state getter', () => {
+    const machine = new ViewportInteractionStateMachine()
+    machine.begin(gesture)
+    const snapshot = machine.state!
+    snapshot.currentX = 99
+    snapshot.xDomain[0] = 50
+    snapshot.yDomains.track![0] = 50
+
+    expect(machine.state).toMatchObject({ currentX: 10, xDomain: [0, 100] })
+    expect(machine.state?.yDomains.track).toEqual([-1, 1])
+  })
+})
--- a/src/components/interaction/viewportInteractionState.ts
+++ b/src/components/interaction/viewportInteractionState.ts
@@ -0,0 +1,80 @@
+import type { ViewportSelectionState } from '../core/waveformChartTypes'
+
+export interface ViewportGestureStart {
+  trackIndex: number
+  independent: boolean
+  startX: number
+  startY: number
+  pointerId: number
+  kind: 'box' | 'pan'
+  xDomain: [number, number]
+  yDomains: Record<string, [number, number]>
+}
+
+export interface ViewportGesturePosition {
+  currentX: number
+  currentY: number
+}
+
+function cloneState(state: ViewportSelectionState | null): ViewportSelectionState | null {
+  if (!state) return null
+  return {
+    ...state,
+    xDomain: [...state.xDomain],
+    yDomains: Object.fromEntries(
+      Object.entries(state.yDomains).map(([key, domain]) => [key, [...domain] as [number, number]]),
+    ),
+  }
+}
+
+/** Owns the legal lifecycle of one active viewport pointer gesture. */
+export class ViewportInteractionStateMachine {
+  private current: ViewportSelectionState | null = null
+
+  get state(): ViewportSelectionState | null {
+    return cloneState(this.current)
+  }
+
+  begin(input: ViewportGestureStart): boolean {
+    if (this.current) return false
+    this.current = {
+      ...input,
+      currentX: input.startX,
+      currentY: input.startY,
+      xDomain: [...input.xDomain],
+      yDomains: Object.fromEntries(
+        Object.entries(input.yDomains).map(([key, domain]) => [
+          key,
+          [...domain] as [number, number],
+        ]),
+      ),
+    }
+    return true
+  }
+
+  move(pointerId: number, position: ViewportGesturePosition): ViewportSelectionState | null {
+    if (!this.current || this.current.pointerId !== pointerId) return null
+    this.current = { ...this.current, ...position }
+    return this.state
+  }
+
+  finish(pointerId: number, position: ViewportGesturePosition): ViewportSelectionState | null {
+    if (!this.current || this.current.pointerId !== pointerId) return null
+    this.current = { ...this.current, ...position }
+    const completed = this.state
+    this.current = null
+    return completed
+  }
+
+  cancel(pointerId?: number): boolean {
+    if (!this.current || (pointerId !== undefined && this.current.pointerId !== pointerId)) {
+      return false
+    }
+    this.current = null
+    return true
+  }
+
+  reset(): void {
+    this.current = null
+  }
+}
--- a/src/components/rendering/WaveformTrack.vue
+++ b/src/components/rendering/WaveformTrack.vue
@@ -94,7 +94,7 @@ const resolvedFrameStyle = computed(() => {
    />

    <rect
-      v-if="!track.isEmpty && !cleanView"
+      v-if="!track.isEmpty"
      class="waveform-track__plot-frame waveform-chart__plot-frame"
      :width="track.width ?? innerWidth"
      :height="track.height"
--- a/src/components/rendering/WaveformTrackAxes.vue
+++ b/src/components/rendering/WaveformTrackAxes.vue
@@ -3,7 +3,7 @@ import { axisBottom, axisLeft, axisRight, select } from 'd3'
 import { nextTick, onMounted, ref, watch } from 'vue'

 import type { WaveformAxesOptions } from '../../types'
-import { formatAxisTime, formatScientificAxisLabel } from '../../utils'
+import { formatScientificAxisLabel, formatXAxisLabel } from '../../utils'
 import type { DisplaySeries, TrackLayout, WaveformYAxisLayout } from '../core/types'

 interface Props {
@@ -43,8 +43,11 @@ function renderAxes() {
    const element = yAxisElements.value[index]
    if (!element) return
    const [axisMin, axisMax] = axis.scale.domain()
+    const topTickValue = Math.max(...axis.tickValues)
    const yAxis = (axis.side === 'left' ? axisLeft(axis.scale) : axisRight(axis.scale))
-      .tickFormat((value) => formatScientificAxisLabel(Number(value), { axisMin, axisMax }))
+      .tickFormat((value) =>
+        formatScientificAxisLabel(Number(value), { axisMin, axisMax, topTickValue }),
+      )
      .tickSize(-4)
      .tickPadding(7)
      .tickSizeOuter(0)
@@ -63,10 +66,12 @@ function renderAxes() {
    axisBottom(props.track.xScale)
      .tickValues(props.track.xAxisTickValues)
      .tickFormat((value) =>
-        formatAxisTime(
+        formatXAxisLabel(
          Number(value),
-          props.timeUnit,
          props.track.xScale.domain() as [number, number],
+          props.timeUnit,
+          'tick',
+          props.axes?.x?.labelFormatter,
        ),
      )
      .tickSize(-4)
@@ -90,6 +95,7 @@ watch(
    () => props.track.xAxisTickValues,
    () => props.track.yAxisTickValues,
    () => props.timeUnit,
+    () => props.axes?.x?.labelFormatter,
    () => props.axes?.x?.lineVisible,
    () => props.axes?.y?.lineVisible,
  ],
@@ -103,14 +109,14 @@ watch(

 <template>
  <g
-    v-if="track.showXAxis && !cleanView"
+    v-if="track.showXAxis"
    ref="xAxisElement"
    class="waveform-track__axis waveform-track__axis--x waveform-chart__axis waveform-chart__axis--x"
    :class="{ 'waveform-track__axis--line-hidden': axes?.x?.lineVisible === false }"
    :transform="`translate(0, ${track.height})`"
  />
  <g
-    v-if="track.showXAxis && !cleanView"
+    v-if="track.showXAxis"
    class="waveform-track__axis-endpoints waveform-chart__axis-endpoints"
    :transform="`translate(0, ${track.height})`"
    font-family="sans-serif"
@@ -136,19 +142,8 @@ watch(
      {{ track.endpointLabels.end }}
    </text>
  </g>
-  <text
-    v-if="track.showXAxis && track.xAxisExponent && !cleanView"
-    class="waveform-track__axis-exponent waveform-track__axis-exponent--x waveform-chart__axis-exponent waveform-chart__axis-exponent--x"
-    :x="track.width ?? innerWidth"
-    :y="track.height + 27"
-    text-anchor="end"
-    aria-hidden="true"
-  >
-    {{ track.xAxisExponent }}
-  </text>
-
  <g
-    v-for="axis in track.isEmpty || cleanView ? [] : track.yAxes"
+    v-for="axis in track.isEmpty ? [] : track.yAxes"
    :key="`y-axis-${track.index}-${axis.index}`"
    :ref="(element) => setYAxisElement(element, axis.index)"
    class="waveform-track__axis waveform-track__axis--y waveform-chart__axis waveform-chart__axis--y"
@@ -160,22 +155,6 @@ watch(
    :data-y-axis-side="axis.side"
    :transform="`translate(${axis.x}, 0)`"
  />
-  <text
-    v-for="axis in track.isEmpty || cleanView
-      ? []
-      : track.yAxes.filter((item) => item.exponentLabel)"
-    :key="`y-axis-exponent-${track.index}-${axis.index}`"
-    class="waveform-track__axis-exponent waveform-track__axis-exponent--y waveform-chart__axis-exponent waveform-chart__axis-exponent--y"
-    :data-y-axis-index="axis.index"
-    :x="axis.exponentX"
-    y="0"
-    dy="0.32em"
-    :text-anchor="axis.side === 'left' ? 'end' : 'start'"
-    aria-hidden="true"
-  >
-    {{ axis.exponentLabel }}
-  </text>
-
  <g
    v-if="
      !cleanView &&
--- a/src/components/waveform.ts
+++ b/src/components/waveform.ts
@@ -12,6 +12,7 @@ export type {
  WaveformAnnotationStyle,
  WaveformAnnotation,
  WaveformRenderingOptions,
+  WaveformPlotMargin,
  WaveformTitleTextStyle,
  WaveformTitleOptions,
  WaveformFrameStyle,
--- a/src/components/waveformChartCases/compactAndSharedHover.test.ts
+++ b/src/components/waveformChartCases/compactAndSharedHover.test.ts
@@ -72,7 +72,7 @@ describe('WaveformChart', () => {
    expect(endTicks[3]).toHaveLength(0)
  })

-  it('keeps one separate shared exponent for every compact Y axis', async () => {
+  it('prefixes one shared exponent to the largest visible tick on every compact Y axis', async () => {
    const wrapper = await mountSizedChart(
      {
        kind: 'series',
@@ -83,7 +83,7 @@ describe('WaveformChart', () => {
              kind: 'points',
              points: [
                { x: 0, y: 0 },
-                { x: 1, y: 254 },
+                { x: 1, y: 2540 },
              ],
            },
          },
@@ -103,14 +103,14 @@ describe('WaveformChart', () => {
    )

    const axes = wrapper.findAll('.waveform-chart__axis--y')
-    const exponents = wrapper.findAll('.waveform-chart__axis-exponent--y')
    expect(axes).toHaveLength(2)
-    expect(exponents.map((label) => label.text())).toEqual(['E+02', 'E-04'])
-    axes.forEach((axis) => {
+    axes.forEach((axis, index) => {
      const labels = axis.findAll('.tick text').map((tick) => tick.text())
-      expect(labels.every((label) => !label.startsWith('E'))).toBe(true)
-      expect(labels.every((label) => /^-?\d+\.\d{2}$/.test(label))).toBe(true)
+      const exponentLabels = labels.filter((label) => label.startsWith('E'))
+      expect(exponentLabels).toHaveLength(1)
+      expect(exponentLabels[0]).toMatch(index === 0 ? /^E\+03 / : /^E-04 /)
    })
+    expect(wrapper.find('.waveform-chart__axis-exponent--y').exists()).toBe(false)
  })

  it('prefers a trimmed series name and falls back to yLabel for unnamed data', async () => {
--- a/src/components/waveformChartCases/dataAndHoverPerformance.test.ts
+++ b/src/components/waveformChartCases/dataAndHoverPerformance.test.ts
@@ -178,7 +178,7 @@ describe('WaveformChart', () => {
    await flushPromises()
    expect(wrapper.emitted('point-hover')?.at(-1)).toEqual([{ x: 1, y: 5 }])
    expect(wrapper.find('.waveform-chart__tooltip').exists()).toBe(true)
-    expect(wrapper.get('.waveform-chart__tooltip').text()).toContain('ms: 1,000.0000')
+    expect(wrapper.get('.waveform-chart__tooltip-time').text()).toBe('ms: 1,000')
    const crosshairLines = wrapper.findAll('.waveform-chart__crosshair line')
    expect(crosshairLines).toHaveLength(1)
    expect(crosshairLines[0].attributes('x1')).toBe(crosshairLines[0].attributes('x2'))
@@ -303,7 +303,7 @@ describe('WaveformChart', () => {
    flushAnimationFrames()
    await flushPromises()

-    expect(wrapper.get('.waveform-chart__tooltip').text()).toContain('ms: 1,000.0000')
+    expect(wrapper.get('.waveform-chart__tooltip-time').text()).toBe('ms: 1,000')
    expect(wrapper.findAll('.waveform-chart__crosshair line')).toHaveLength(1)
    expect(wrapper.get('.waveform-chart__line').element).toBe(pathBeforeHover)
    expect(chartUpdate).not.toHaveBeenCalled()
--- a/src/components/waveformChartCases/dataLifecycle.test.ts
+++ b/src/components/waveformChartCases/dataLifecycle.test.ts
@@ -62,15 +62,15 @@ describe('WaveformChart', () => {
      ],
    }
    const wrapper = await mountSizedChart(firstData)
-    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('1.00')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('1000')

    firstData.points.push({ x: 2, y: 2 })
    await flushPromises()
-    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('1.00')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('1000')

    await wrapper.setProps({ data: { ...firstData, points: [...firstData.points] } })
    await flushPromises()
-    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('2.00')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('2000')
  })

  it('keeps controlled annotations when replacing the loaded data window', async () => {
@@ -170,7 +170,7 @@ describe('WaveformChart', () => {
    expect(wrapper.findAll('.waveform-chart__track-label')).toHaveLength(0)
    expect(
      wrapper.findAll('.waveform-chart__axis-endpoint--end').map((item) => item.text()),
-    ).toEqual(['1.00', '2.00'])
+    ).toEqual(['1000', '2000'])
  })

  it('keeps the zero Y-axis label on upper compact tracks', async () => {
--- a/src/components/waveformChartCases/frameGridAndFormatting.test.ts
+++ b/src/components/waveformChartCases/frameGridAndFormatting.test.ts
@@ -1,7 +1,8 @@
 import { flushPromises } from '@vue/test-utils'
-import { describe, expect, it } from 'vitest'
+import { describe, expect, it, vi } from 'vitest'

 import { flushAnimationFrames } from '../../test/setup'
+import type { WaveformXAxisLabelFormatter } from '../../types'
 import { type WaveformData } from '../waveform'

 import { gridSeries, mountSizedChart } from '../../test/waveformChart'
@@ -162,35 +163,42 @@ describe('WaveformChart', () => {
    expect(wrapper.get('.waveform-chart__axis-endpoint--end').attributes('x')).toBe(
      String(trackWidth),
    )
-    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('4.99')
-    expect(wrapper.get('.waveform-chart__axis-exponent--x').text()).toBe('E+03')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('4990.3')
+    expect(wrapper.find('.waveform-chart__axis-exponent--x').exists()).toBe(false)
  })

  it('uses one shared scientific exponent only for large and tiny Y-axis domains', async () => {
    const cases = [
-      { values: [0, 50], exponent: null },
-      { values: [0, 254], exponent: 'E+02' },
-      { values: [0, 0.0002], exponent: 'E-04' },
+      { values: [0, 50], yDomain: [0, 50] as [number, number], exponent: null },
+      { values: [1000, 3000], yDomain: [1000, 3000] as [number, number], exponent: 'E+03' },
+      {
+        values: [0.0001, 0.0003],
+        yDomain: [0.0001, 0.0003] as [number, number],
+        exponent: 'E-04',
+      },
    ]

-    for (const { values, exponent } of cases) {
-      const wrapper = await mountSizedChart({
-        kind: 'points',
+    for (const { values, yDomain, exponent } of cases) {
+      const data = {
+        kind: 'points' as const,
        points: values.map((y, x) => ({ x, y })),
-      })
+      }
+      const originalValues = data.points.map((point) => point.y)
+      const wrapper = await mountSizedChart(data, { yDomain })
      const labels = wrapper
        .get('.waveform-chart__axis--y')
        .findAll('.tick text')
        .map((tick) => tick.text())
-      const exponentLabel = wrapper.find('.waveform-chart__axis-exponent--y')
+      const exponentLabels = labels.filter((label) => label.startsWith('E'))

      if (exponent === null) {
-        expect(exponentLabel.exists()).toBe(false)
+        expect(exponentLabels).toHaveLength(0)
      } else {
-        expect(exponentLabel.text()).toBe(exponent)
-        expect(labels.every((label) => !label.startsWith('E'))).toBe(true)
-        expect(labels.every((label) => /^-?\d+\.\d{2}$/.test(label))).toBe(true)
+        expect(exponentLabels).toHaveLength(1)
+        expect(exponentLabels[0]).toMatch(new RegExp(`^${exponent.replace('+', '\\+')} `))
      }
+      expect(wrapper.find('.waveform-chart__axis-exponent--y').exists()).toBe(false)
+      expect(data.points.map((point) => point.y)).toEqual(originalValues)

      wrapper.unmount()
    }
@@ -212,13 +220,13 @@ describe('WaveformChart', () => {

    expect(millisecondsChart.text()).toContain('时间（ms）')
    expect(millisecondTicks.length).toBeGreaterThan(0)
-    expect(millisecondsChart.get('.waveform-chart__axis-endpoint--end').text()).toBe('1.00')
-    expect(millisecondsChart.get('.waveform-chart__axis-exponent--x').text()).toBe('E+03')
+    expect(millisecondsChart.get('.waveform-chart__axis-endpoint--end').text()).toBe('1000')
+    expect(millisecondsChart.find('.waveform-chart__axis-exponent--x').exists()).toBe(false)
    expect(millisecondsChart.find('.waveform-chart__watermark').exists()).toBe(false)

    const secondsChart = await mountSizedChart(data, { timeUnit: 's', xLabel: 'Elapsed time' })
    expect(secondsChart.text()).toContain('Elapsed time')
-    expect(secondsChart.get('.waveform-chart__axis-endpoint--end').text()).toBe('1.00')
+    expect(secondsChart.get('.waveform-chart__axis-endpoint--end').text()).toBe('1')
    expect(secondsChart.find('.waveform-chart__axis-exponent--x').exists()).toBe(false)
  })

@@ -237,15 +245,15 @@ describe('WaveformChart', () => {

    expect(start.attributes('x')).toBe('0')
    expect(start.attributes('text-anchor')).toBe('start')
-    expect(start.text()).toBe('0.00')
+    expect(start.text()).toBe('0')
    expect(end.attributes('x')).toBe(
      wrapper.get('.waveform-chart__track').attributes('data-track-width'),
    )
    expect(end.attributes('text-anchor')).toBe('end')
-    expect(end.text()).toBe('2.00')
+    expect(end.text()).toBe('1999')
    expect(middleTickLabels.length).toBeGreaterThan(0)
-    expect(middleTickLabels).not.toContain('0.00')
-    expect(wrapper.get('.waveform-chart__axis-exponent--x').text()).toBe('E+03')
+    expect(middleTickLabels).not.toContain('0')
+    expect(wrapper.find('.waveform-chart__axis-exponent--x').exists()).toBe(false)
    expect(wrapper.findAll('.waveform-chart__grid--major line').length).toBeGreaterThan(
      middleTickLabels.length,
    )
@@ -260,6 +268,70 @@ describe('WaveformChart', () => {
    expect(endpointGroup.attributes('font-size')).toBe(xAxis.attributes('font-size'))
  })

+  it('formats X-axis ticks and endpoints with display-unit values and source context', async () => {
+    const data: WaveformData = {
+      kind: 'points',
+      points: [
+        { x: 0.125, y: 0 },
+        { x: 1.875, y: 1 },
+      ],
+    }
+    const originalPoints = data.points.map((point) => ({ ...point }))
+    const labelFormatter: WaveformXAxisLabelFormatter = (value, context) =>
+      `${context.kind}:${value / 10}`
+    const formatter = vi.fn(labelFormatter)
+    const wrapper = await mountSizedChart(data, {
+      timeUnit: 'ms',
+      axes: { x: { labelFormatter: formatter } },
+    })
+
+    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).toBe('start:12.5')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('end:187.5')
+    expect(
+      wrapper
+        .get('.waveform-chart__axis--x')
+        .findAll('.tick text')
+        .every((tick) => tick.text().startsWith('tick:')),
+    ).toBe(true)
+
+    const startCall = formatter.mock.calls.find(([, context]) => context.kind === 'start')
+    const tickCall = formatter.mock.calls.find(([, context]) => context.kind === 'tick')
+    const endCall = formatter.mock.calls.find(([, context]) => context.kind === 'end')
+    expect(startCall).toEqual([
+      125,
+      {
+        kind: 'start',
+        rawValue: 0.125,
+        timeUnit: 'ms',
+        domain: [0.125, 1.875],
+        displayDomain: [125, 1875],
+      },
+    ])
+    expect(tickCall?.[0]).toBeTypeOf('number')
+    expect(tickCall?.[1]).toMatchObject({
+      kind: 'tick',
+      timeUnit: 'ms',
+      domain: [0.125, 1.875],
+      displayDomain: [125, 1875],
+    })
+    expect(endCall?.[1]).toMatchObject({ kind: 'end', rawValue: 1.875 })
+    expect(data.points).toEqual(originalPoints)
+
+    await wrapper.setProps({
+      axes: { x: { labelFormatter: (value: number) => `updated:${value}` } },
+    })
+    await flushPromises()
+    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).toBe('updated:125')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('updated:1875')
+    expect(
+      wrapper
+        .get('.waveform-chart__axis--x')
+        .findAll('.tick text')
+        .every((tick) => tick.text().startsWith('updated:')),
+    ).toBe(true)
+    expect(data.points).toEqual(originalPoints)
+  })
+
  it('keeps zoom-change domains in source seconds', async () => {
    const wrapper = await mountSizedChart({
      kind: 'points',
@@ -300,6 +372,8 @@ describe('WaveformChart', () => {
    )
    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).not.toBe(initialStart)
    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).not.toBe(initialEnd)
-    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).toContain('.')
+    expect(
+      Number.isFinite(Number(wrapper.get('.waveform-chart__axis-endpoint--start').text())),
+    ).toBe(true)
  })
 })
--- a/src/components/waveformChartCases/interactionAndAnnotationCreation.test.ts
+++ b/src/components/waveformChartCases/interactionAndAnnotationCreation.test.ts
@@ -59,7 +59,7 @@ describe('WaveformChart', () => {
    await flushPromises()

    expect(wrapper.findAll('.waveform-chart__axis--x')).toHaveLength(1)
-    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('2.00')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('2000')
  })

  it('updates rendering props and disables zoom interaction', async () => {
--- a/src/components/waveformChartCases/layoutAndDomains.test.ts
+++ b/src/components/waveformChartCases/layoutAndDomains.test.ts
@@ -33,10 +33,10 @@ describe('WaveformChart', () => {
      tracks[0].get('.waveform-chart__y-axis-label-bg').attributes('x'),
    )

-    expect(labelX).toBe(-103)
+    expect(labelX).toBe(-74)
    expect(labelBackgroundX).toBe(labelX - 12)
-    expect(Number(wrapper.attributes('data-chart-left-margin'))).toBe(119)
-    expect(secondLeft - firstWidth).toBeGreaterThanOrEqual(119)
+    expect(Number(wrapper.attributes('data-chart-left-margin'))).toBe(90)
+    expect(secondLeft - firstWidth).toBeGreaterThanOrEqual(90)
  })

  it('keeps a tick-only gutter when channel labels are empty', async () => {
@@ -62,8 +62,8 @@ describe('WaveformChart', () => {
    const secondLeft = Number(tracks[1].attributes('data-track-left'))

    expect(wrapper.findAll('.waveform-chart__y-axis-label')).toHaveLength(0)
-    expect(Number(wrapper.attributes('data-chart-left-margin'))).toBe(89)
-    expect(secondLeft - firstWidth).toBeGreaterThanOrEqual(89)
+    expect(Number(wrapper.attributes('data-chart-left-margin'))).toBe(64)
+    expect(secondLeft - firstWidth).toBeGreaterThanOrEqual(60)
  })

  it('keeps the Y-axis label gutter stable while paging between value ranges', async () => {
@@ -122,7 +122,7 @@ describe('WaveformChart', () => {
    const tracks = wrapper.findAll('.waveform-chart__track')
    const firstWidth = Number(tracks[0].attributes('data-track-width'))
    const secondLeft = Number(tracks[1].attributes('data-track-left'))
-    expect(secondLeft - firstWidth).toBeGreaterThanOrEqual(39)
+    expect(secondLeft - firstWidth).toBeGreaterThanOrEqual(32)
  })

  it('uses one shared overlay and bottom-row x axes for separated and compact grids', async () => {
@@ -225,7 +225,7 @@ describe('WaveformChart', () => {
    }
  })

-  it('uses each track x domain in independent mode instead of the shared initial domain', async () => {
+  it('uses the shared initial x domain for every independent track by default', async () => {
    const wrapper = await mountSizedChart(
      {
        kind: 'series',
@@ -262,8 +262,10 @@ describe('WaveformChart', () => {
    )

    const tracks = wrapper.findAll('.waveform-chart__track')
-    expect(tracks[0]?.get('.waveform-chart__axis-endpoint--end').text()).toBe('6.00')
-    expect(tracks[1]?.get('.waveform-chart__axis-endpoint--end').text()).toBe('5.00')
+    expect(tracks[0]?.get('.waveform-chart__axis-endpoint--start').text()).toBe('-8000')
+    expect(tracks[0]?.get('.waveform-chart__axis-endpoint--end').text()).toBe('5000')
+    expect(tracks[1]?.get('.waveform-chart__axis-endpoint--start').text()).toBe('-8000')
+    expect(tracks[1]?.get('.waveform-chart__axis-endpoint--end').text()).toBe('5000')
  })

  it('uses an explicit initial x domain override for an independent track', async () => {
@@ -291,7 +293,32 @@ describe('WaveformChart', () => {
      },
    )

-    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('1.00')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('1000')
+  })
+
+  it('reacts to exact fixed Y-domain props and returns to automatic bounds', async () => {
+    const wrapper = await mountSizedChart({
+      kind: 'points',
+      points: [
+        { x: 0, y: 0 },
+        { x: 1, y: 100 },
+      ],
+    })
+    const yTickLabels = () =>
+      wrapper
+        .get('.waveform-chart__axis--y')
+        .findAll('.tick text')
+        .map((tick) => tick.text())
+
+    await wrapper.setProps({ yDomain: [3, 97] })
+    await flushPromises()
+    expect(yTickLabels()).toContain('3')
+    expect(yTickLabels()).toContain('97')
+
+    await wrapper.setProps({ yDomain: undefined })
+    await flushPromises()
+    expect(yTickLabels()).not.toContain('3')
+    expect(yTickLabels()).not.toContain('97')
  })

  it('keeps annotations bound to their channel while paging', async () => {
--- a/src/components/waveformChartCases/multiAxisAndPagination.test.ts
+++ b/src/components/waveformChartCases/multiAxisAndPagination.test.ts
@@ -30,7 +30,7 @@ describe('WaveformChart', () => {
              kind: 'points',
              points: [
                { x: 0, y: 0 },
-                { x: 1, y: 254 },
+                { x: 1, y: 2540 },
              ],
            },
          },
@@ -51,13 +51,13 @@ describe('WaveformChart', () => {
    )

    expect(
-      wrapper
-        .findAll('.waveform-chart__axis-exponent--y')
-        .map((label) => [label.attributes('data-y-axis-index'), label.text()]),
-    ).toEqual([
-      ['1', 'E+02'],
-      ['2', 'E-04'],
-    ])
+      wrapper.findAll('.waveform-chart__axis--y').map((axis) =>
+        axis
+          .findAll('.tick text')
+          .map((label) => label.text())
+          .filter((label) => label.startsWith('E')),
+      ),
+    ).toEqual([[], [expect.stringMatching(/^E\+03 /)], [expect.stringMatching(/^E-04 /)]])
  })

  it('reprojects annotations with the Y axis assigned to their series', async () => {
--- a/src/components/waveformChartCases/presentationAndAxes.test.ts
+++ b/src/components/waveformChartCases/presentationAndAxes.test.ts
@@ -54,8 +54,9 @@ describe('WaveformChart', () => {
      ],
    })

-    expect(first.find('.waveform-chart__axis-exponent--y').exists()).toBe(false)
-    expect(second.get('.waveform-chart__axis-exponent--y').text()).toBe('E+04')
+    expect(first.get('.waveform-chart__axis--y').text()).not.toContain('E')
+    expect(second.get('.waveform-chart__axis--y').text()).toContain('E+04 ')
+    expect(second.find('.waveform-chart__axis-exponent--y').exists()).toBe(false)
  })

  it('renders a configurable zero line only when the Y domain contains zero', async () => {
@@ -146,7 +147,7 @@ describe('WaveformChart', () => {
            kind: 'points',
            points: [
              { x: 0, y: -1 },
-              { x: 1, y: 1 },
+              { x: 10_000, y: 1 },
            ],
          },
        },
@@ -227,8 +228,8 @@ describe('WaveformChart', () => {
          data: {
            kind: 'points',
            points: [
-              { x: 0, y: 1 },
-              { x: 1, y: 2 },
+              { x: 0, y: 10_000 },
+              { x: 10_000, y: 20_000 },
            ],
          },
        },
@@ -239,7 +240,7 @@ describe('WaveformChart', () => {
            kind: 'points',
            points: [
              { x: 0, y: 2 },
-              { x: 1, y: 3 },
+              { x: 10_000, y: 3 },
            ],
          },
        },
@@ -252,6 +253,8 @@ describe('WaveformChart', () => {
      annotations: [{ id: 'note', seriesId: 'first', x: 0.5, y: 0, text: 'hidden note' }],
      zeroLine: { visible: true },
      title: { text: 'hidden title' },
+      axes: { x: { lineVisible: false }, y: { lineVisible: false } },
+      frameStyle: { borderColor: '#dc2626', borderWidth: 2, borderStyle: 'dashed' as const },
    }
    const regularWrapper = await mountSizedChart(data, sharedProps)
    const wrapper = await mountSizedChart(data, {
@@ -285,13 +288,32 @@ describe('WaveformChart', () => {
    expect(wrapper.find('.waveform-chart__overlay--independent').exists()).toBe(true)
    expect(wrapper.get('.waveform-chart__title-area').attributes('aria-hidden')).toBe('true')
    expect(wrapper.find('.waveform-chart__title-visual').exists()).toBe(false)
-    expect(wrapper.find('.waveform-chart__axis').exists()).toBe(false)
+    const xAxis = wrapper.get('.waveform-chart__axis--x')
+    const yAxes = wrapper.findAll('.waveform-chart__axis--y')
+    expect(yAxes).toHaveLength(2)
+    expect(xAxis.findAll('.tick line').length).toBeGreaterThan(0)
+    expect(xAxis.findAll('.tick text').length).toBeGreaterThan(0)
+    yAxes.forEach((axis) => {
+      expect(axis.findAll('.tick line').length).toBeGreaterThan(0)
+      expect(axis.findAll('.tick text').length).toBeGreaterThan(0)
+      expect(axis.get('path.domain').attributes('display')).toBe('none')
+    })
+    expect(xAxis.get('path.domain').attributes('display')).toBe('none')
+    expect(wrapper.findAll('.waveform-chart__axis-endpoint')).toHaveLength(2)
+    expect(wrapper.find('.waveform-chart__axis-exponent--x').exists()).toBe(false)
+    expect(yAxes.some((axis) => axis.text().includes('E+04 '))).toBe(true)
+    expect(wrapper.find('.waveform-chart__axis-exponent--y').exists()).toBe(false)
    expect(wrapper.find('.waveform-chart__grid').exists()).toBe(false)
-    expect(wrapper.find('.waveform-chart__plot-frame').exists()).toBe(false)
+    expect(wrapper.get('.waveform-chart__plot-frame').attributes()).toMatchObject({
+      stroke: '#dc2626',
+      'stroke-width': '2',
+      'stroke-dasharray': '6 4',
+    })
    expect(wrapper.find('.waveform-chart__plot-background').exists()).toBe(false)
    expect(wrapper.find('.waveform-chart__watermark').exists()).toBe(false)
    expect(wrapper.find('.waveform-chart__legend-layer').exists()).toBe(false)
    expect(wrapper.find('.waveform-chart__label').exists()).toBe(false)
+    expect(wrapper.find('.waveform-chart__y-axis-label').exists()).toBe(false)
    expect(wrapper.find('.waveform-chart__zero-line').exists()).toBe(false)
    expect(wrapper.find('.waveform-annotation-layer').exists()).toBe(false)
    expect(wrapper.find('.ant-pagination').exists()).toBe(false)
--- a/src/components/waveformChartCases/presentationMode.test.ts
+++ b/src/components/waveformChartCases/presentationMode.test.ts
@@ -241,7 +241,7 @@ describe('WaveformChart presentation mode', () => {
    await flushPromises()
    overlay.element.dispatchEvent(
      new WheelEvent('wheel', {
-        deltaY: -200,
+        deltaY: 200,
        clientX: width / 2,
        clientY: height / 2,
        bubbles: true,
--- a/src/components/waveformChartCases/sizingAndTitles.test.ts
+++ b/src/components/waveformChartCases/sizingAndTitles.test.ts
@@ -105,6 +105,65 @@ describe('WaveformChart', () => {
    expect(wrapper.get('.waveform-chart__svg').attributes('height')).toBe('300')
  })

+  it('configures plot top and bottom margins and reacts to updates', async () => {
+    const wrapper = await mountSizedChart(
+      { kind: 'samples', values: [0, 1], sampleRate: 1 },
+      {
+        displayMode: 'compact',
+        grid: { rowCount: 1, columnCount: 1 },
+        plotMargin: { top: 30, bottom: 70 },
+      },
+    )
+
+    expect(wrapper.attributes('data-plot-margin-top')).toBe('30')
+    expect(wrapper.attributes('data-plot-margin-bottom')).toBe('70')
+    expect(wrapper.get('.waveform-chart__overlay').attributes('height')).toBe('260')
+    expect(wrapper.get('.waveform-chart__svg > g').attributes('transform')).toContain(', 30)')
+
+    await wrapper.setProps({ plotMargin: { top: 12 } })
+
+    expect(wrapper.attributes('data-plot-margin-top')).toBe('12')
+    expect(wrapper.attributes('data-plot-margin-bottom')).toBe('52')
+    expect(wrapper.get('.waveform-chart__overlay').attributes('height')).toBe('296')
+  })
+
+  it('falls back to default plot margins for invalid values', async () => {
+    const wrapper = await mountSizedChart(
+      { kind: 'samples', values: [0, 1], sampleRate: 1 },
+      {
+        displayMode: 'compact',
+        grid: { rowCount: 1, columnCount: 1 },
+        plotMargin: { top: -1, bottom: Number.NaN },
+      },
+    )
+
+    expect(wrapper.attributes('data-plot-margin-top')).toBe('18')
+    expect(wrapper.attributes('data-plot-margin-bottom')).toBe('52')
+    expect(wrapper.get('.waveform-chart__overlay').attributes('height')).toBe('290')
+  })
+
+  it('keeps the chart title and X-axis title fixed when plot margins change', async () => {
+    const wrapper = await mountSizedChart(
+      { kind: 'samples', values: [0, 1], sampleRate: 1 },
+      {
+        displayMode: 'compact',
+        grid: { rowCount: 1, columnCount: 1 },
+        title: { text: '固定标题' },
+      },
+    )
+    const titleAreaStyle = wrapper.get('.waveform-chart__title-area').attributes('style')
+    const xAxisTitle = wrapper.get('.waveform-chart__x-label')
+    const initialX = xAxisTitle.attributes('x')
+    const initialY = xAxisTitle.attributes('y')
+
+    await wrapper.setProps({ plotMargin: { top: 60, bottom: 90 } })
+
+    expect(wrapper.get('.waveform-chart__title-area').attributes('style')).toBe(titleAreaStyle)
+    expect(wrapper.get('.waveform-chart__x-label').attributes('x')).toBe(initialX)
+    expect(wrapper.get('.waveform-chart__x-label').attributes('y')).toBe(initialY)
+    expect(wrapper.get('.waveform-chart__svg > g').attributes('transform')).toContain(', 60)')
+  })
+
  it('does not render or reserve space for missing, hidden, or blank titles', async () => {
    for (const title of [undefined, { visible: false, text: '隐藏标题' }, { text: '   ' }]) {
      const wrapper = await mountSizedChart(
--- a/src/components/waveformChartCases/viewportBoxAndPan.test.ts
+++ b/src/components/waveformChartCases/viewportBoxAndPan.test.ts
@@ -38,6 +38,21 @@ describe('WaveformChart', () => {
    expect(domain[1]).toBeLessThanOrEqual(1)
    expect(endpoints()[0]).not.toBe(initialEndpoints[0])
    expect(endpoints()[1]).toBe(initialEndpoints[1])
+
+    overlays[0].element.dispatchEvent(
+      new WheelEvent('wheel', {
+        deltaY: 4_000,
+        clientX: firstWidth - 1,
+        clientY: 130,
+        bubbles: true,
+        cancelable: true,
+      }),
+    )
+    flushAnimationFrames()
+    await flushPromises()
+
+    expect(endpoints()[0]).toBe(initialEndpoints[0])
+    expect(endpoints()[1]).toBe(initialEndpoints[1])
  })

  it('emits one zoom-end payload after a shared zoom gesture completes', async () => {
@@ -224,6 +239,56 @@ describe('WaveformChart', () => {
    window.dispatchEvent(new KeyboardEvent('keyup', { code: 'Space' }))
  })

+  it('keeps a fixed Y domain through panning and viewport reset', async () => {
+    const wrapper = await mountSizedChart(
+      {
+        kind: 'points',
+        points: [
+          { x: 0, y: 0 },
+          { x: 1, y: 100 },
+        ],
+      },
+      { pannable: true, yDomain: [3, 97] },
+    )
+    const overlay = wrapper.get('.waveform-chart__overlay--independent')
+    const width = Number(overlay.attributes('width'))
+    const height = Number(overlay.attributes('height'))
+    Object.defineProperty(overlay.element, 'getBoundingClientRect', {
+      value: () => ({ left: 0, top: 0, width, height }),
+    })
+    const yTickLabels = () =>
+      wrapper
+        .get('.waveform-chart__axis--y')
+        .findAll('.tick text')
+        .map((tick) => tick.text())
+    const initialLabels = yTickLabels()
+
+    await wrapper.trigger('pointerenter')
+    window.dispatchEvent(new KeyboardEvent('keydown', { code: 'Space', cancelable: true }))
+    const down = new MouseEvent('pointerdown', {
+      button: 0,
+      clientX: width / 2,
+      clientY: height / 2,
+      bubbles: true,
+    })
+    Object.defineProperty(down, 'pointerId', { value: 34 })
+    overlay.element.dispatchEvent(down)
+    const move = new MouseEvent('pointermove', {
+      clientX: width / 2 + 20,
+      clientY: height / 2 + 40,
+      bubbles: true,
+    })
+    Object.defineProperty(move, 'pointerId', { value: 34 })
+    overlay.element.dispatchEvent(move)
+    await flushPromises()
+
+    expect(yTickLabels()).toEqual(initialLabels)
+    ;(wrapper.vm as unknown as { resetViewport: () => void }).resetViewport()
+    await flushPromises()
+    expect(yTickLabels()).toEqual(initialLabels)
+    window.dispatchEvent(new KeyboardEvent('keyup', { code: 'Space' }))
+  })
+
  it('does not activate pannable on a chart that the pointer is outside', async () => {
    const data: WaveformData = {
      kind: 'points',
--- a/src/components/waveformChartCases/viewportConstraintsAndReset.test.ts
+++ b/src/components/waveformChartCases/viewportConstraintsAndReset.test.ts
@@ -79,8 +79,8 @@ describe('WaveformChart', () => {

    expect(wrapper.emitted('zoom-change')).toBeUndefined()
    expect(wrapper.emitted('zoom-end')).toBeUndefined()
-    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).toBe('0.00')
-    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('2.00')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).toBe('0')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('2000')
  })

  it('ignores independent viewport dragging', async () => {
@@ -207,7 +207,7 @@ describe('WaveformChart', () => {
    expect(secondDomain[1] - secondDomain[0]).toBeCloseTo(10)
  })

-  it('keeps one global domain while loading narrower and wider windows', async () => {
+  it('zooms a shared viewport back out after loading a narrower data window', async () => {
    const wrapper = await mountSizedChart(
      {
        kind: 'points',
@@ -256,9 +256,57 @@ describe('WaveformChart', () => {

    const eventCount = wrapper.emitted('zoom-change')?.length ?? 0
    await dispatchWheel(4000)
-    const currentDomain = wrapper.emitted('zoom-change')?.at(-1)?.[0] as [number, number]
+    const zoomedOutDomain = wrapper.emitted('zoom-change')?.at(-1)?.[0] as [number, number]
+    expect(wrapper.emitted('zoom-change')?.length ?? 0).toBe(eventCount + 1)
+    expect(zoomedOutDomain[1] - zoomedOutDomain[0]).toBeCloseTo(100)
+
+    const fullDomainEventCount = wrapper.emitted('zoom-change')?.length ?? 0
+    await dispatchWheel(4000)
+    expect(wrapper.emitted('zoom-change')?.length ?? 0).toBe(fullDomainEventCount)
+  })
+
+  it('allows zooming out when the minimum visible point count blocks zooming in', async () => {
+    const wrapper = await mountSizedChart({
+      kind: 'points',
+      points: [
+        { x: 0, y: 0 },
+        { x: 1, y: 10 },
+        { x: 2, y: 20 },
+      ],
+    })
+    const overlay = wrapper.get('.waveform-chart__overlay--independent')
+    const width = Number(overlay.attributes('width'))
+    Object.defineProperty(overlay.element, 'getBoundingClientRect', {
+      value: () => ({ left: 0, top: 0, width, height: 290 }),
+    })
+    const dispatchWheel = async (deltaY: number) => {
+      overlay.element.dispatchEvent(
+        new WheelEvent('wheel', {
+          deltaY,
+          clientX: width / 2,
+          clientY: 145,
+          bubbles: true,
+          cancelable: true,
+        }),
+      )
+      flushAnimationFrames()
+      await flushPromises()
+    }
+
+    await dispatchWheel(-4000)
+    const zoomedDomain = wrapper.emitted('zoom-change')?.at(-1)?.[0] as [number, number]
+    expect(zoomedDomain[1] - zoomedDomain[0]).toBeCloseTo(0.05)
+
+    await wrapper.setProps({ minVisiblePoints: 10 })
+    await flushPromises()
+    const eventCount = wrapper.emitted('zoom-change')?.length ?? 0
+    await dispatchWheel(-1000)
    expect(wrapper.emitted('zoom-change')?.length ?? 0).toBe(eventCount)
-    expect(currentDomain[1] - currentDomain[0]).toBeCloseTo(2.5)
+
+    await dispatchWheel(4000)
+    const zoomedOutDomain = wrapper.emitted('zoom-change')?.at(-1)?.[0] as [number, number]
+    expect(wrapper.emitted('zoom-change')?.length ?? 0).toBe(eventCount + 1)
+    expect(zoomedOutDomain).toEqual([0, 2])
  })

  it('resets a shared viewport on double-click and emits zoom-reset', async () => {
@@ -285,14 +333,14 @@ describe('WaveformChart', () => {
    )
    flushAnimationFrames()
    await flushPromises()
-    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).not.toBe('0.00')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).not.toBe('0')

    overlay.element.dispatchEvent(new MouseEvent('dblclick', { bubbles: true, cancelable: true }))
    await flushPromises()

    expect(wrapper.emitted('zoom-reset')).toHaveLength(1)
-    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).toBe('0.00')
-    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('2.00')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).toBe('0')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--end').text()).toBe('2000')
  })

  it('exposes resetViewport for independent tracks', async () => {
@@ -316,13 +364,13 @@ describe('WaveformChart', () => {
    )
    flushAnimationFrames()
    await flushPromises()
-    expect(wrapper.findAll('.waveform-chart__axis-endpoint--start')[0].text()).not.toBe('0.00')
+    expect(wrapper.findAll('.waveform-chart__axis-endpoint--start')[0].text()).not.toBe('0')

    const chart = wrapper.vm as unknown as { resetViewport: () => void }
    chart.resetViewport()
    await flushPromises()

-    expect(wrapper.findAll('.waveform-chart__axis-endpoint--start')[0].text()).toBe('0.00')
-    expect(wrapper.findAll('.waveform-chart__axis-endpoint--end')[0].text()).toBe('1.00')
+    expect(wrapper.findAll('.waveform-chart__axis-endpoint--start')[0].text()).toBe('0')
+    expect(wrapper.findAll('.waveform-chart__axis-endpoint--end')[0].text()).toBe('1000')
  })
 })
--- a/src/components/waveformChartCases/wheelZoomOut.test.ts
+++ b/src/components/waveformChartCases/wheelZoomOut.test.ts
@@ -0,0 +1,114 @@
+import { flushPromises } from '@vue/test-utils'
+import { describe, expect, it, vi } from 'vitest'
+
+import { flushAnimationFrames } from '../../test/setup'
+import { mountSizedChart } from '../../test/waveformChart'
+
+describe('WaveformChart wheel zoom out', () => {
+  it('restores an independent initial domain after replacing data with a narrow window', async () => {
+    const createData = (start: number, end: number) => ({
+      kind: 'series' as const,
+      series: [
+        {
+          id: 'channel-a',
+          name: '通道 A',
+          data: {
+            kind: 'points' as const,
+            points: [
+              { x: start, y: 0 },
+              { x: end, y: 1 },
+            ],
+          },
+        },
+      ],
+    })
+    const wrapper = await mountSizedChart(createData(-5, 5), {
+      displayMode: 'independent',
+      initialXDomain: [-5, 5],
+    })
+    const overlay = wrapper.get('.waveform-chart__overlay--independent')
+    const overlayWidth = Number(overlay.attributes('width'))
+    Object.defineProperty(overlay.element, 'getBoundingClientRect', {
+      value: () => ({ left: 0, top: 0, width: overlayWidth, height: 290 }),
+    })
+    const dispatchWheel = async (deltaY: number) => {
+      overlay.element.dispatchEvent(
+        new WheelEvent('wheel', {
+          deltaY,
+          clientX: overlayWidth / 2,
+          clientY: 145,
+          bubbles: true,
+          cancelable: true,
+        }),
+      )
+      flushAnimationFrames()
+      await flushPromises()
+    }
+    const endpoints = () => ({
+      start: wrapper.get('.waveform-chart__axis-endpoint--start').text(),
+      end: wrapper.get('.waveform-chart__axis-endpoint--end').text(),
+    })
+
+    expect(endpoints()).toEqual({ start: '-5000', end: '5000' })
+    await dispatchWheel(-4000)
+    expect(endpoints()).not.toEqual({ start: '-5000', end: '5000' })
+
+    await wrapper.setProps({ data: createData(-0.125, 0.125) })
+    await flushPromises()
+    await dispatchWheel(4000)
+
+    expect(endpoints()).toEqual({ start: '-5000', end: '5000' })
+  })
+
+  it('emits one zoom-end payload after zooming a shared viewport out', async () => {
+    vi.useFakeTimers()
+    try {
+      const wrapper = await mountSizedChart({
+        kind: 'points',
+        points: [
+          { x: 0, y: 0 },
+          { x: 2, y: 1 },
+        ],
+      })
+      const overlay = wrapper.get('.waveform-chart__overlay')
+      const overlayWidth = Number(overlay.attributes('width'))
+      Object.defineProperty(overlay.element, 'getBoundingClientRect', {
+        value: () => ({ left: 0, top: 0, width: overlayWidth, height: 290 }),
+      })
+      const dispatchWheel = (deltaY: number) =>
+        overlay.element.dispatchEvent(
+          new WheelEvent('wheel', {
+            deltaY,
+            clientX: overlayWidth / 2,
+            clientY: 145,
+            bubbles: true,
+            cancelable: true,
+          }),
+        )
+
+      dispatchWheel(-4000)
+      flushAnimationFrames()
+      await vi.advanceTimersByTimeAsync(200)
+      await flushPromises()
+      const zoomedDomain = wrapper.emitted('zoom-change')?.at(-1)?.[0] as [number, number]
+      const zoomedSpan = zoomedDomain[1] - zoomedDomain[0]
+
+      dispatchWheel(1000)
+      flushAnimationFrames()
+      expect(wrapper.emitted('zoom-end')).toHaveLength(1)
+      await vi.advanceTimersByTimeAsync(200)
+      await flushPromises()
+
+      const zoomedOutPayload = wrapper.emitted('zoom-end')?.at(-1)?.[0] as {
+        start: number
+        end: number
+        gesture: string
+      }
+      expect(wrapper.emitted('zoom-end')).toHaveLength(2)
+      expect(zoomedOutPayload.end - zoomedOutPayload.start).toBeGreaterThan(zoomedSpan)
+      expect(zoomedOutPayload.gesture).toBe('wheel')
+    } finally {
+      vi.useRealTimers()
+    }
+  })
+})
--- a/src/core/rendering.ts
+++ b/src/core/rendering.ts
@@ -3,6 +3,10 @@ import { bisector } from 'd3'
 import type { WaveformPoint } from '@/types'
 import { resolveWaveformPointErrors } from './data'
 import type { ResolvedWaveformRenderingOptions } from './renderingOptions'
+import {
+  resolveRenderablePointSelectionStrategy,
+  type VisiblePointRange,
+} from './renderingStrategies'

 export {
  DEFAULT_WAVEFORM_RENDERING_OPTIONS,
@@ -13,11 +17,6 @@ export {
 const pointBisector = bisector((point: WaveformPoint) => point.x)
 const acceptAllPoints = () => true

-interface VisiblePointRange {
-  start: number
-  end: number
-}
-
 interface PointSeriesSource {
  points: WaveformPoint[]
 }
@@ -65,10 +64,6 @@ export function hasMinimumVisibleXValues(
  return false
 }

-function pushUniquePoint(target: WaveformPoint[], point: WaveformPoint | undefined) {
-  if (point && target[target.length - 1] !== point) target.push(point)
-}
-
 function selectRenderablePointsInRange(
  points: WaveformPoint[],
  range: VisiblePointRange,
@@ -76,82 +71,17 @@ function selectRenderablePointsInRange(
  width: number,
  options: ResolvedWaveformRenderingOptions,
 ): WaveformPoint[] {
-  const domainStart = Math.min(domain[0], domain[1])
-  const domainEnd = Math.max(domain[0], domain[1])
  const start = Math.max(0, range.start - 1)
  const end = Math.min(points.length, range.end + 1)
  const visibleCount = end - start
  if (visibleCount <= 0) return []
-  if (!options.downsample || visibleCount <= options.downsampleThreshold) {
-    return points.slice(start, end)
-  }
-
-  const maximumPointCount = Math.max(4, Math.floor(width * options.maxPointsPerPixel))
-  const bucketCount = Math.max(1, Math.floor(maximumPointCount / 4))
-  if (visibleCount <= maximumPointCount) return points.slice(start, end)
-
-  const result: WaveformPoint[] = []
-  const span = domainEnd - domainStart || 1
-  const bucketIndexes = Array.from({ length: 4 }, () => -1)
-  let activeBucket = -1
-  let firstIndex = -1
-  let lastIndex = -1
-  let minimumIndex = -1
-  let maximumIndex = -1
-
-  const addBucketIndex = (index: number, count: number) => {
-    if (index < 0) return count
-    for (let position = 0; position < count; position += 1) {
-      if (bucketIndexes[position] === index) return count
-    }
-    bucketIndexes[count] = index
-    return count + 1
-  }
-
-  const flushBucket = () => {
-    if (firstIndex < 0) return
-    let count = 0
-    count = addBucketIndex(firstIndex, count)
-    count = addBucketIndex(minimumIndex, count)
-    count = addBucketIndex(maximumIndex, count)
-    count = addBucketIndex(lastIndex, count)
-    for (let index = 1; index < count; index += 1) {
-      const value = bucketIndexes[index]
-      let position = index - 1
-      while (position >= 0 && bucketIndexes[position] > value) {
-        bucketIndexes[position + 1] = bucketIndexes[position]
-        position -= 1
-      }
-      bucketIndexes[position + 1] = value
-    }
-    for (let index = 0; index < count; index += 1) {
-      pushUniquePoint(result, points[bucketIndexes[index]])
-    }
-  }
-
-  pushUniquePoint(result, points[start])
-  for (let index = range.start; index < range.end; index += 1) {
-    const point = points[index]
-    const bucket = Math.min(
-      bucketCount - 1,
-      Math.max(0, Math.floor(((point.x - domainStart) / span) * bucketCount)),
-    )
-    if (bucket !== activeBucket) {
-      flushBucket()
-      activeBucket = bucket
-      firstIndex = index
-      lastIndex = index
-      minimumIndex = index
-      maximumIndex = index
-      continue
-    }
-    lastIndex = index
-    if (point.y < points[minimumIndex].y) minimumIndex = index
-    if (point.y > points[maximumIndex].y) maximumIndex = index
-  }
-  flushBucket()
-  pushUniquePoint(result, points[end - 1])
-  return result
+  return resolveRenderablePointSelectionStrategy({ visibleCount, width, options }).select({
+    points,
+    range,
+    domain,
+    width,
+    options,
+  })
 }

 /**
--- a/src/core/renderingStrategies.test.ts
+++ b/src/core/renderingStrategies.test.ts
@@ -0,0 +1,78 @@
+import { describe, expect, it } from 'vitest'
+
+import type { WaveformPoint } from '../types'
+import { DEFAULT_WAVEFORM_RENDERING_OPTIONS } from './renderingOptions'
+import {
+  CompletePointSelectionStrategy,
+  PeakPreservingPointSelectionStrategy,
+  resolveRenderablePointSelectionStrategy,
+} from './renderingStrategies'
+
+const denseOptions = {
+  ...DEFAULT_WAVEFORM_RENDERING_OPTIONS,
+  downsampleThreshold: 0,
+  maxPointsPerPixel: 1,
+}
+
+describe('renderable point selection strategies', () => {
+  it('resolves complete-point selection at the configured boundaries', () => {
+    const complete = resolveRenderablePointSelectionStrategy({
+      visibleCount: 100,
+      width: 100,
+      options: DEFAULT_WAVEFORM_RENDERING_OPTIONS,
+    })
+    const disabled = resolveRenderablePointSelectionStrategy({
+      visibleCount: 10_000,
+      width: 100,
+      options: { ...denseOptions, downsample: false },
+    })
+
+    expect(complete).toBeInstanceOf(CompletePointSelectionStrategy)
+    expect(disabled).toBeInstanceOf(CompletePointSelectionStrategy)
+  })
+
+  it('resolves peak-preserving selection for dense visible data', () => {
+    const strategy = resolveRenderablePointSelectionStrategy({
+      visibleCount: 1_000,
+      width: 100,
+      options: denseOptions,
+    })
+
+    expect(strategy).toBeInstanceOf(PeakPreservingPointSelectionStrategy)
+    expect(strategy.name).toBe('peak-preserving')
+  })
+
+  it('reuses the resolved strategy instance across selections', () => {
+    const request = { visibleCount: 100, width: 100, options: DEFAULT_WAVEFORM_RENDERING_OPTIONS }
+    const peakRequest = { visibleCount: 1_000, width: 100, options: denseOptions }
+
+    expect(resolveRenderablePointSelectionStrategy(request)).toBe(
+      resolveRenderablePointSelectionStrategy(request),
+    )
+    expect(resolveRenderablePointSelectionStrategy(peakRequest)).toBe(
+      resolveRenderablePointSelectionStrategy(peakRequest),
+    )
+  })
+
+  it('retains first, last, minimum, and maximum points in a peak bucket', () => {
+    const points: WaveformPoint[] = [
+      { x: 0, y: 5 },
+      { x: 1, y: 1 },
+      { x: 2, y: 10 },
+      { x: 3, y: 3 },
+      { x: 4, y: 7 },
+    ]
+    const strategy = new PeakPreservingPointSelectionStrategy()
+    const selected = strategy.select({
+      points,
+      range: { start: 0, end: points.length },
+      domain: [0, 4],
+      width: 4,
+      options: denseOptions,
+    })
+
+    expect(selected[0]).toBe(points[0])
+    expect(selected.at(-1)).toBe(points.at(-1))
+    expect(selected.map((point) => point.y)).toEqual(expect.arrayContaining([1, 10]))
+  })
+})
--- a/src/core/renderingStrategies.ts
+++ b/src/core/renderingStrategies.ts
@@ -0,0 +1,149 @@
+import type { WaveformPoint } from '../types'
+import type { ResolvedWaveformRenderingOptions } from './renderingOptions'
+
+export interface VisiblePointRange {
+  start: number
+  end: number
+}
+
+export interface RenderablePointSelectionContext {
+  points: WaveformPoint[]
+  range: VisiblePointRange
+  domain: [number, number]
+  width: number
+  options: ResolvedWaveformRenderingOptions
+}
+
+export interface RenderablePointSelectionStrategy {
+  readonly name: 'complete' | 'peak-preserving'
+  select(context: RenderablePointSelectionContext): WaveformPoint[]
+}
+
+function selectionBounds(range: VisiblePointRange, pointCount: number) {
+  return {
+    start: Math.max(0, range.start - 1),
+    end: Math.min(pointCount, range.end + 1),
+  }
+}
+
+function pushUniquePoint(target: WaveformPoint[], point: WaveformPoint | undefined) {
+  if (point && target[target.length - 1] !== point) target.push(point)
+}
+
+export class CompletePointSelectionStrategy implements RenderablePointSelectionStrategy {
+  readonly name = 'complete' as const
+
+  select(context: RenderablePointSelectionContext): WaveformPoint[] {
+    const { start, end } = selectionBounds(context.range, context.points.length)
+    return context.points.slice(start, end)
+  }
+}
+
+export class PeakPreservingPointSelectionStrategy implements RenderablePointSelectionStrategy {
+  readonly name = 'peak-preserving' as const
+
+  select(context: RenderablePointSelectionContext): WaveformPoint[] {
+    const { points, range, domain, width, options } = context
+    const { start, end } = selectionBounds(range, points.length)
+    const visibleCount = end - start
+    if (visibleCount <= 0) return []
+
+    const domainStart = Math.min(domain[0], domain[1])
+    const domainEnd = Math.max(domain[0], domain[1])
+    const maximumPointCount = Math.max(4, Math.floor(width * options.maxPointsPerPixel))
+    const bucketCount = Math.max(1, Math.floor(maximumPointCount / 4))
+    const result: WaveformPoint[] = []
+    const span = domainEnd - domainStart || 1
+    const bucketIndexes = Array.from({ length: 4 }, () => -1)
+    let activeBucket = -1
+    let firstIndex = -1
+    let lastIndex = -1
+    let minimumIndex = -1
+    let maximumIndex = -1
+
+    const addBucketIndex = (index: number, count: number) => {
+      if (index < 0) return count
+      for (let position = 0; position < count; position += 1) {
+        if (bucketIndexes[position] === index) return count
+      }
+      bucketIndexes[count] = index
+      return count + 1
+    }
+
+    const flushBucket = () => {
+      if (firstIndex < 0) return
+      let count = 0
+      count = addBucketIndex(firstIndex, count)
+      count = addBucketIndex(minimumIndex, count)
+      count = addBucketIndex(maximumIndex, count)
+      count = addBucketIndex(lastIndex, count)
+      for (let index = 1; index < count; index += 1) {
+        const value = bucketIndexes[index]
+        let position = index - 1
+        while (position >= 0 && bucketIndexes[position] > value) {
+          bucketIndexes[position + 1] = bucketIndexes[position]
+          position -= 1
+        }
+        bucketIndexes[position + 1] = value
+      }
+      for (let index = 0; index < count; index += 1) {
+        pushUniquePoint(result, points[bucketIndexes[index]])
+      }
+    }
+
+    pushUniquePoint(result, points[start])
+    for (let index = range.start; index < range.end; index += 1) {
+      const point = points[index]
+      const bucket = Math.min(
+        bucketCount - 1,
+        Math.max(0, Math.floor(((point.x - domainStart) / span) * bucketCount)),
+      )
+      if (bucket !== activeBucket) {
+        flushBucket()
+        activeBucket = bucket
+        firstIndex = index
+        lastIndex = index
+        minimumIndex = index
+        maximumIndex = index
+        continue
+      }
+      lastIndex = index
+      if (point.y < points[minimumIndex].y) minimumIndex = index
+      if (point.y > points[maximumIndex].y) maximumIndex = index
+    }
+    flushBucket()
+    pushUniquePoint(result, points[end - 1])
+    return result
+  }
+}
+
+export interface RenderablePointSelectionStrategyRequest {
+  visibleCount: number
+  width: number
+  options: ResolvedWaveformRenderingOptions
+}
+
+export class RenderablePointSelectionStrategyFactory {
+  private readonly complete = new CompletePointSelectionStrategy()
+  private readonly peakPreserving = new PeakPreservingPointSelectionStrategy()
+
+  resolve(request: RenderablePointSelectionStrategyRequest): RenderablePointSelectionStrategy {
+    const maximumPointCount = Math.max(
+      4,
+      Math.floor(request.width * request.options.maxPointsPerPixel),
+    )
+    const shouldUseCompletePoints =
+      !request.options.downsample ||
+      request.visibleCount <= request.options.downsampleThreshold ||
+      request.visibleCount <= maximumPointCount
+    return shouldUseCompletePoints ? this.complete : this.peakPreserving
+  }
+}
+
+const defaultRenderablePointSelectionStrategyFactory = new RenderablePointSelectionStrategyFactory()
+
+export function resolveRenderablePointSelectionStrategy(
+  request: RenderablePointSelectionStrategyRequest,
+): RenderablePointSelectionStrategy {
+  return defaultRenderablePointSelectionStrategyFactory.resolve(request)
+}
--- a/src/demo/DemoChartHost.vue
+++ b/src/demo/DemoChartHost.vue
@@ -45,6 +45,7 @@ defineExpose({ resetViewport })
      :clean-view="model.cleanView"
      :presentation-mode="model.presentationMode"
      :show-tooltip="model.showTooltip"
+      :plot-margin="model.plotMargin"
      :zero-line="model.zeroLine"
      :frame-number="model.frameWatermarkVisible ? 1 : undefined"
      :annotations-visible="model.annotationsVisible"
--- a/src/demo/DemoGridFrameControls.vue
+++ b/src/demo/DemoGridFrameControls.vue
@@ -8,6 +8,35 @@ const model = defineModel<DemoControlPanelModel>('model', { required: true })
 </script>

 <template>
+  <section class="control-section">
+    <h2>绘图区边距</h2>
+    <div class="plot-margin-controls">
+      <label class="frame-style-control">
+        <span>上边距</span>
+        <InputNumber
+          v-model:value="model.plotMarginTop"
+          :min="0"
+          :max="300"
+          :step="1"
+          addon-after="px"
+          size="small"
+          aria-label="绘图区上边距"
+        />
+      </label>
+      <label class="frame-style-control">
+        <span>下边距</span>
+        <InputNumber
+          v-model:value="model.plotMarginBottom"
+          :min="0"
+          :max="300"
+          :step="1"
+          addon-after="px"
+          size="small"
+          aria-label="绘图区下边距"
+        />
+      </label>
+    </div>
+  </section>
  <section class="control-section">
    <div class="control-section__header">
      <h2>零值参考线</h2>
@@ -96,6 +125,76 @@ const model = defineModel<DemoControlPanelModel>('model', { required: true })
        <Switch v-model:checked="model.yAxisLineVisible" size="small" aria-label="显示纵轴线" />
      </div>
    </div>
+    <div class="x-axis-label-controls">
+      <label class="frame-style-control frame-style-control--switch">
+        <span>自定义 Label</span>
+        <Switch
+          v-model:checked="model.xAxisLabelFormatterEnabled"
+          size="small"
+          aria-label="自定义 X 轴 Label"
+        />
+      </label>
+      <label v-if="model.xAxisLabelFormatterEnabled" class="frame-style-control">
+        <span>格式类型</span>
+        <Select
+          v-model:value="model.xAxisLabelFormat"
+          :options="model.xAxisLabelFormatOptions"
+          size="small"
+          aria-label="X 轴 Label 格式类型"
+        />
+      </label>
+      <label
+        v-if="model.xAxisLabelFormatterEnabled && model.xAxisLabelFormat === 'number'"
+        class="frame-style-control"
+      >
+        <span>运算倍率</span>
+        <InputNumber
+          v-model:value="model.xAxisLabelMultiplier"
+          :min="-1000000"
+          :max="1000000"
+          :step="0.1"
+          size="small"
+          aria-label="X 轴 Label 运算倍率"
+        />
+      </label>
+      <label
+        v-if="model.xAxisLabelFormatterEnabled && model.xAxisLabelFormat === 'number'"
+        class="frame-style-control"
+      >
+        <span>小数位数</span>
+        <InputNumber
+          v-model:value="model.xAxisLabelFractionDigits"
+          :min="0"
+          :max="12"
+          :step="1"
+          size="small"
+          aria-label="X 轴 Label 小数位数"
+        />
+      </label>
+      <label
+        v-if="model.xAxisLabelFormatterEnabled && model.xAxisLabelFormat === 'datetime'"
+        class="frame-style-control"
+      >
+        <span>时区</span>
+        <Select
+          v-model:value="model.xAxisLabelTimeZone"
+          :options="model.xAxisLabelTimeZoneOptions"
+          size="small"
+          aria-label="X 轴 Label 时区"
+        />
+      </label>
+      <label
+        v-if="model.xAxisLabelFormatterEnabled && model.xAxisLabelFormat === 'datetime'"
+        class="frame-style-control frame-style-control--switch"
+      >
+        <span>显示毫秒</span>
+        <Switch
+          v-model:checked="model.xAxisLabelShowMilliseconds"
+          size="small"
+          aria-label="X 轴 Label 显示毫秒"
+        />
+      </label>
+    </div>
  </section>
  <section class="control-section">
    <h2>图框样式</h2>
--- a/src/demo/plotMarginControls.test.ts
+++ b/src/demo/plotMarginControls.test.ts
@@ -0,0 +1,29 @@
+import { flushPromises, mount } from '@vue/test-utils'
+import { InputNumber } from 'ant-design-vue'
+import { describe, expect, it } from 'vitest'
+
+import App from '../App.vue'
+import { WaveformChart } from '../components'
+
+describe('plot margin demo controls', () => {
+  it('updates the chart top and bottom margins from the sidebar', async () => {
+    const wrapper = mount(App)
+    await flushPromises()
+    const chart = wrapper.getComponent(WaveformChart)
+    const controls = wrapper.get('.plot-margin-controls').findAllComponents(InputNumber)
+
+    expect(controls).toHaveLength(2)
+    expect(controls[0]?.props('value')).toBe(18)
+    expect(controls[1]?.props('value')).toBe(52)
+    expect(chart.props('plotMargin')).toEqual({ top: 18, bottom: 52 })
+
+    controls[0]?.vm.$emit('update:value', 30)
+    controls[1]?.vm.$emit('update:value', 70)
+    await flushPromises()
+
+    expect(chart.props('plotMargin')).toEqual({ top: 30, bottom: 70 })
+    expect(wrapper.get('.waveform-chart').attributes('data-plot-margin-top')).toBe('30')
+    expect(wrapper.get('.waveform-chart').attributes('data-plot-margin-bottom')).toBe('70')
+    wrapper.unmount()
+  })
+})
--- a/src/demo/types.ts
+++ b/src/demo/types.ts
@@ -10,10 +10,12 @@ import type {
  WaveformLegendPosition,
  WaveformLineStyle,
  WaveformOverlayMode,
+  WaveformPlotMargin,
  WaveformTitleOptions,
  WaveformZeroLineOptions,
  WaveformZoomEndPayload,
 } from '../components'
+import type { DemoXAxisLabelFormat, DemoXAxisLabelTimeZone } from './useDemoXAxisLabelControls'

 interface SelectOption<T> {
  label: string
@@ -25,6 +27,8 @@ export interface DemoControlPanelModel {
  displayMode: WaveformDisplayMode
  overlayMode: WaveformOverlayMode
  showTooltip: boolean
+  plotMarginTop: number
+  plotMarginBottom: number
  cleanView: boolean
  presentationMode: boolean
  selectedSeriesId: string
@@ -44,6 +48,14 @@ export interface DemoControlPanelModel {
  verticalGridColor: string
  xAxisLineVisible: boolean
  yAxisLineVisible: boolean
+  xAxisLabelFormatterEnabled: boolean
+  xAxisLabelFormat: DemoXAxisLabelFormat
+  xAxisLabelFormatOptions: Array<SelectOption<DemoXAxisLabelFormat>>
+  xAxisLabelMultiplier: number
+  xAxisLabelFractionDigits: number
+  xAxisLabelTimeZone: DemoXAxisLabelTimeZone
+  xAxisLabelTimeZoneOptions: Array<SelectOption<DemoXAxisLabelTimeZone>>
+  xAxisLabelShowMilliseconds: boolean
  frameBorderColor: string
  frameBackgroundColor: string
  frameBorderWidth: number
@@ -90,6 +102,7 @@ export interface DemoChartModel {
  cleanView: boolean
  presentationMode: boolean
  showTooltip: boolean
+  plotMargin: WaveformPlotMargin
  zeroLine: WaveformZeroLineOptions
  frameWatermarkVisible: boolean
  annotations: WaveformAnnotation[]
--- a/src/demo/useDemoXAxisLabelControls.ts
+++ b/src/demo/useDemoXAxisLabelControls.ts
@@ -0,0 +1,77 @@
+import { computed, ref } from 'vue'
+
+import type { WaveformXAxisLabelFormatter } from '../types'
+
+export type DemoXAxisLabelFormat = 'number' | 'datetime'
+export type DemoXAxisLabelTimeZone = 'local' | 'Asia/Shanghai' | 'UTC'
+
+const formatOptions = [
+  { label: '数值', value: 'number' as const },
+  { label: '固定时间', value: 'datetime' as const },
+]
+const timeZoneOptions = [
+  { label: '中国标准时间', value: 'Asia/Shanghai' as const },
+  { label: '本地时区', value: 'local' as const },
+  { label: 'UTC', value: 'UTC' as const },
+]
+
+function pad(value: number, length = 2): string {
+  return String(value).padStart(length, '0')
+}
+
+export function formatDemoTimestamp(
+  value: number,
+  timeZone: DemoXAxisLabelTimeZone,
+  showMilliseconds: boolean,
+): string {
+  const offset = timeZone === 'Asia/Shanghai' ? 8 * 60 * 60 * 1000 : 0
+  const date = new Date(value + offset)
+  if (!Number.isFinite(date.getTime())) return String(value)
+
+  const useUtcFields = timeZone !== 'local'
+  const year = useUtcFields ? date.getUTCFullYear() : date.getFullYear()
+  const month = (useUtcFields ? date.getUTCMonth() : date.getMonth()) + 1
+  const day = useUtcFields ? date.getUTCDate() : date.getDate()
+  const hours = useUtcFields ? date.getUTCHours() : date.getHours()
+  const minutes = useUtcFields ? date.getUTCMinutes() : date.getMinutes()
+  const seconds = useUtcFields ? date.getUTCSeconds() : date.getSeconds()
+  const milliseconds = useUtcFields ? date.getUTCMilliseconds() : date.getMilliseconds()
+  const suffix = showMilliseconds ? `.${pad(milliseconds, 3)}` : ''
+  return `${year}-${pad(month)}-${pad(day)} ${pad(hours)}:${pad(minutes)}:${pad(seconds)}${suffix}`
+}
+
+export function useDemoXAxisLabelControls() {
+  const xAxisLabelFormatterEnabled = ref(false)
+  const xAxisLabelFormat = ref<DemoXAxisLabelFormat>('number')
+  const xAxisLabelMultiplier = ref(1)
+  const xAxisLabelFractionDigits = ref(3)
+  const xAxisLabelTimeZone = ref<DemoXAxisLabelTimeZone>('Asia/Shanghai')
+  const xAxisLabelShowMilliseconds = ref(false)
+  const xAxisLabelFormatter = computed<WaveformXAxisLabelFormatter | undefined>(() => {
+    if (!xAxisLabelFormatterEnabled.value) return undefined
+    if (xAxisLabelFormat.value === 'datetime') {
+      return (value) =>
+        formatDemoTimestamp(value, xAxisLabelTimeZone.value, xAxisLabelShowMilliseconds.value)
+    }
+
+    const multiplier = Number.isFinite(xAxisLabelMultiplier.value) ? xAxisLabelMultiplier.value : 1
+    const fractionDigits = Number.isFinite(xAxisLabelFractionDigits.value)
+      ? Math.min(12, Math.max(0, Math.trunc(xAxisLabelFractionDigits.value)))
+      : 0
+    return (value) => (value * multiplier).toFixed(fractionDigits)
+  })
+
+  return {
+    controlModel: {
+      xAxisLabelFormatterEnabled,
+      xAxisLabelFormat,
+      xAxisLabelFormatOptions: formatOptions,
+      xAxisLabelMultiplier,
+      xAxisLabelFractionDigits,
+      xAxisLabelTimeZone,
+      xAxisLabelTimeZoneOptions: timeZoneOptions,
+      xAxisLabelShowMilliseconds,
+    },
+    xAxisLabelFormatter,
+  }
+}
--- a/src/demo/xAxisLabelControls.test.ts
+++ b/src/demo/xAxisLabelControls.test.ts
@@ -0,0 +1,86 @@
+import { flushPromises, mount } from '@vue/test-utils'
+import { InputNumber, Select } from 'ant-design-vue'
+import { describe, expect, it } from 'vitest'
+
+import App from '../App.vue'
+import { WaveformChart } from '../components'
+import { formatDemoTimestamp } from './useDemoXAxisLabelControls'
+
+describe('X-axis label demo controls', () => {
+  it('formats timestamps in fixed UTC and China-standard-time formats', () => {
+    expect(formatDemoTimestamp(0, 'UTC', false)).toBe('1970-01-01 00:00:00')
+    expect(formatDemoTimestamp(123, 'UTC', true)).toBe('1970-01-01 00:00:00.123')
+    expect(formatDemoTimestamp(0, 'Asia/Shanghai', false)).toBe('1970-01-01 08:00:00')
+    expect(formatDemoTimestamp(Number.NaN, 'UTC', false)).toBe('NaN')
+  })
+
+  it('configures numeric and timestamp labels from the sidebar', async () => {
+    const wrapper = mount(App)
+    await flushPromises()
+    const chart = wrapper.getComponent(WaveformChart)
+
+    expect(chart.props('axes')).toEqual({
+      x: { lineVisible: false },
+      y: { lineVisible: false },
+    })
+    expect(wrapper.find('[aria-label="自定义 X 轴 Label"]').exists()).toBe(true)
+    expect(wrapper.find('[aria-label="X 轴 Label 运算倍率"]').exists()).toBe(false)
+    expect(wrapper.find('[aria-label="X 轴 Label 小数位数"]').exists()).toBe(false)
+    expect(wrapper.find('[aria-label="X 轴 Label 格式类型"]').exists()).toBe(false)
+
+    await wrapper.get('[aria-label="自定义 X 轴 Label"]').trigger('click')
+    await flushPromises()
+    const inputNumbers = wrapper.findAllComponents(InputNumber)
+    const multiplierInput = inputNumbers.find((input) =>
+      input.find('[aria-label="X 轴 Label 运算倍率"]').exists(),
+    )
+    const fractionDigitsInput = inputNumbers.find((input) =>
+      input.find('[aria-label="X 轴 Label 小数位数"]').exists(),
+    )
+    expect(multiplierInput).toBeDefined()
+    expect(fractionDigitsInput).toBeDefined()
+    expect(multiplierInput?.props('value')).toBe(1)
+    expect(fractionDigitsInput?.props('value')).toBe(3)
+    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).toMatch(/\.000$/)
+
+    multiplierInput?.vm.$emit('update:value', 2)
+    fractionDigitsInput?.vm.$emit('update:value', 2)
+    await flushPromises()
+    const formatter = chart.props('axes')?.x?.labelFormatter
+    expect(formatter).toBeTypeOf('function')
+    expect(formatter?.(1.234, {} as never)).toBe('2.47')
+    expect(wrapper.get('.waveform-chart__axis-endpoint--start').text()).toMatch(/\.00$/)
+
+    const formatSelect = wrapper
+      .findAllComponents(Select)
+      .find((select) => select.find('[aria-label="X 轴 Label 格式类型"]').exists())
+    expect(formatSelect?.props('value')).toBe('number')
+    formatSelect?.vm.$emit('update:value', 'datetime')
+    await flushPromises()
+    expect(wrapper.find('[aria-label="X 轴 Label 运算倍率"]').exists()).toBe(false)
+    expect(wrapper.find('[aria-label="X 轴 Label 小数位数"]').exists()).toBe(false)
+    expect(wrapper.find('[aria-label="X 轴 Label 时区"]').exists()).toBe(true)
+    expect(wrapper.find('[aria-label="X 轴 Label 显示毫秒"]').exists()).toBe(true)
+    expect(chart.props('axes')?.x?.labelFormatter?.(0, {} as never)).toBe('1970-01-01 08:00:00')
+
+    await wrapper.get('[aria-label="X 轴 Label 显示毫秒"]').trigger('click')
+    await flushPromises()
+    expect(chart.props('axes')?.x?.labelFormatter?.(123, {} as never)).toBe(
+      '1970-01-01 08:00:00.123',
+    )
+    const timeZoneSelect = wrapper
+      .findAllComponents(Select)
+      .find((select) => select.find('[aria-label="X 轴 Label 时区"]').exists())
+    timeZoneSelect?.vm.$emit('update:value', 'UTC')
+    await flushPromises()
+    expect(chart.props('axes')?.x?.labelFormatter?.(123, {} as never)).toBe(
+      '1970-01-01 00:00:00.123',
+    )
+
+    await wrapper.get('[aria-label="自定义 X 轴 Label"]').trigger('click')
+    await flushPromises()
+    expect(chart.props('axes')?.x?.labelFormatter).toBeUndefined()
+    expect(wrapper.find('[aria-label="X 轴 Label 运算倍率"]').exists()).toBe(false)
+    wrapper.unmount()
+  })
+})
--- a/src/demoRoutes.css
+++ b/src/demoRoutes.css
@@ -0,0 +1,197 @@
+.demo-shell {
+  display: grid;
+  grid-template-rows: 48px minmax(0, 1fr);
+  width: 100%;
+  height: 100%;
+  overflow: hidden;
+}
+
+.demo-shell__header {
+  z-index: 40;
+  display: flex;
+  gap: 24px;
+  align-items: center;
+  min-width: 0;
+  padding: 0 16px;
+  background: #fff;
+  border-bottom: 1px solid #e4e7ec;
+}
+
+.demo-shell__brand {
+  flex: 0 0 auto;
+  color: #101828;
+  font-size: 14px;
+  font-weight: 700;
+  text-decoration: none;
+}
+
+.demo-shell__nav {
+  display: flex;
+  align-self: stretch;
+  min-width: 0;
+}
+
+.demo-shell__nav a {
+  display: inline-flex;
+  align-items: center;
+  padding: 0 14px;
+  color: #475467;
+  font-size: 13px;
+  text-decoration: none;
+  border-bottom: 2px solid transparent;
+}
+
+.demo-shell__nav a:hover,
+.demo-shell__nav a:focus-visible,
+.demo-shell__nav a.router-link-exact-active {
+  color: #0958d9;
+}
+
+.demo-shell__nav a.router-link-exact-active {
+  background: #f0f7ff;
+  border-bottom-color: #1677ff;
+}
+
+.demo-shell__content {
+  min-width: 0;
+  min-height: 0;
+  overflow: hidden;
+}
+
+.fixed-domain-demo {
+  display: grid;
+  grid-template-rows: auto auto minmax(0, 1fr);
+  gap: 12px;
+  width: 100%;
+  height: 100%;
+  padding: 16px;
+  overflow: hidden;
+}
+
+.fixed-domain-demo__toolbar {
+  display: flex;
+  gap: 24px;
+  align-items: center;
+  justify-content: space-between;
+  min-width: 0;
+}
+
+.fixed-domain-demo__toolbar h1 {
+  margin: 0;
+  color: #101828;
+  font-size: 18px;
+  font-weight: 700;
+  letter-spacing: 0;
+}
+
+.fixed-domain-demo__toolbar p {
+  margin: 4px 0 0;
+  color: #667085;
+  font-size: 12px;
+}
+
+.fixed-domain-demo__range-controls {
+  display: flex;
+  gap: 16px;
+  align-items: center;
+  min-height: 48px;
+  padding: 8px 12px;
+  background: #fff;
+  border: 1px solid #e4e7ec;
+  border-radius: 6px;
+}
+
+.fixed-domain-demo__range-controls label {
+  display: flex;
+  gap: 8px;
+  align-items: center;
+  color: #475467;
+  font-size: 12px;
+}
+
+.fixed-domain-demo__range-controls .ant-input-number {
+  width: 112px;
+}
+
+.fixed-domain-demo__range-controls strong {
+  color: #344054;
+  font-size: 12px;
+}
+
+.fixed-domain-demo__range-controls strong:not(:first-child) {
+  padding-left: 16px;
+  border-left: 1px solid #e4e7ec;
+}
+
+.fixed-domain-demo__auto-state {
+  color: #667085;
+  font-size: 12px;
+}
+
+.fixed-domain-demo__chart {
+  min-width: 0;
+  min-height: 0;
+  overflow: hidden;
+}
+
+.fixed-domain-demo__chart > .waveform-chart {
+  min-height: 0;
+}
+
+@media (max-width: 900px) {
+  .demo-shell {
+    grid-template-rows: 44px minmax(0, 1fr);
+  }
+
+  .demo-shell__header {
+    gap: 8px;
+    padding: 0 8px;
+  }
+
+  .demo-shell__brand {
+    display: none;
+  }
+
+  .demo-shell__nav {
+    width: 100%;
+  }
+
+  .demo-shell__nav a {
+    flex: 1 1 0;
+    justify-content: center;
+    padding: 0 6px;
+  }
+
+  .fixed-domain-demo {
+    gap: 8px;
+    padding: 10px;
+  }
+
+  .fixed-domain-demo__toolbar {
+    display: grid;
+    gap: 8px;
+  }
+
+  .fixed-domain-demo__toolbar .ant-radio-group {
+    display: flex;
+    width: 100%;
+  }
+
+  .fixed-domain-demo__toolbar .ant-radio-button-wrapper {
+    flex: 1 1 0;
+    padding-inline: 6px;
+    text-align: center;
+  }
+
+  .fixed-domain-demo__range-controls {
+    flex-wrap: wrap;
+    gap: 8px 12px;
+  }
+
+  .fixed-domain-demo__range-controls strong:not(:first-child) {
+    width: 100%;
+    padding: 8px 0 0;
+    border-top: 1px solid #e4e7ec;
+    border-left: 0;
+  }
+}
--- a/src/index.ts
+++ b/src/index.ts
@@ -17,12 +17,16 @@ export type {
  WaveformAnnotationStyle,
  WaveformAnnotation,
  WaveformRenderingOptions,
+  WaveformPlotMargin,
  WaveformTitleTextStyle,
  WaveformTitleOptions,
  WaveformLegendPosition,
  WaveformLegendOrientation,
  WaveformLegendOptions,
  WaveformFrameStyle,
+  WaveformXAxisLabelKind,
+  WaveformXAxisLabelFormatterContext,
+  WaveformXAxisLabelFormatter,
  WaveformAxesOptions,
  WaveformZeroLineOptions,
  // 数据类型
--- a/src/main.ts
+++ b/src/main.ts
@@ -1,7 +1,9 @@
 import { createApp } from 'vue'
 import 'ant-design-vue/dist/antd.css'

-import App from './App.vue'
+import DemoRouterApp from './DemoRouterApp.vue'
+import { router } from './router'
+import './demoRoutes.css'
 import './styles.css'

-createApp(App).mount('#app')
+createApp(DemoRouterApp).use(router).mount('#app')
--- a/src/router.ts
+++ b/src/router.ts
@@ -0,0 +1,21 @@
+import { createRouter, createWebHashHistory, type RouteRecordRaw } from 'vue-router'
+
+import App from './App.vue'
+
+export const routes: RouteRecordRaw[] = [
+  {
+    path: '/',
+    name: 'workspace',
+    component: App,
+  },
+  {
+    path: '/fixed-y-domain',
+    name: 'fixed-y-domain',
+    component: () => import('./views/FixedYDomainDemo.vue'),
+  },
+]
+
+export const router = createRouter({
+  history: createWebHashHistory(),
+  routes,
+})
--- a/src/styles.css
+++ b/src/styles.css
@@ -35,8 +35,7 @@ body {
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 12px;
  width: 100%;
-  height: 100vh;
-  height: 100dvh;
+  height: 100%;
  padding: 12px;
  overflow: hidden;
 }
@@ -134,6 +133,14 @@ body {
  grid-template-columns: minmax(0, 1fr) auto;
 }

+.x-axis-label-controls {
+  display: grid;
+  gap: 10px;
+  margin-top: 12px;
+  padding-top: 12px;
+  border-top: 1px solid #eaecf0;
+}
+
 .grid-line-color-picker,
 .grid-line-color-picker .vc-color-wrap {
  width: 48px;
@@ -188,6 +195,7 @@ body {
 }

 .frame-style-controls,
+.plot-margin-controls,
 .auxiliary-style-controls {
  display: grid;
  gap: 10px;
--- a/src/types/chart.ts
+++ b/src/types/chart.ts
@@ -74,6 +74,14 @@ export interface WaveformRenderingOptions {
  errorBarMinSpacing?: number
 }

+/** Pixel margins reserved above and below the waveform plotting area. */
+export interface WaveformPlotMargin {
+  /** Space between the top of the drawing SVG and the plotting area. Defaults to 18. */
+  top?: number
+  /** Space between the plotting area and the bottom of the drawing SVG. Defaults to 52. */
+  bottom?: number
+}
+
 /** Text styling for the chart-level title. */
 export interface WaveformTitleTextStyle {
  color?: string
@@ -121,10 +129,31 @@ export interface WaveformFrameStyle {
  backgroundColor?: string
 }

+export type WaveformXAxisLabelKind = 'tick' | 'start' | 'end'
+
+/** Context passed to custom X-axis label formatters. */
+export interface WaveformXAxisLabelFormatterContext {
+  kind: WaveformXAxisLabelKind
+  /** X coordinate in the source data, before time-unit conversion. */
+  rawValue: number
+  timeUnit: 's' | 'ms'
+  /** Current visible X domain in source coordinates. */
+  domain: [number, number]
+  /** Current visible X domain converted to the selected display unit. */
+  displayDomain: [number, number]
+}
+
+export type WaveformXAxisLabelFormatter = (
+  value: number,
+  context: WaveformXAxisLabelFormatterContext,
+) => string
+
 /** Controls axis baseline visibility while preserving tick marks and axis text. */
 export interface WaveformAxesOptions {
  x?: {
    lineVisible?: boolean
+    /** Formats display-unit X values for ticks and visible-range endpoints. */
+    labelFormatter?: WaveformXAxisLabelFormatter
  }
  y?: {
    lineVisible?: boolean
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -12,12 +12,16 @@ export type {
  WaveformAnnotationStyle,
  WaveformAnnotation,
  WaveformRenderingOptions,
+  WaveformPlotMargin,
  WaveformTitleTextStyle,
  WaveformTitleOptions,
  WaveformLegendPosition,
  WaveformLegendOrientation,
  WaveformLegendOptions,
  WaveformFrameStyle,
+  WaveformXAxisLabelKind,
+  WaveformXAxisLabelFormatterContext,
+  WaveformXAxisLabelFormatter,
  WaveformAxesOptions,
  WaveformZeroLineOptions,
 } from './chart'
--- a/src/utils/formatters.test.ts
+++ b/src/utils/formatters.test.ts
@@ -1,71 +1,112 @@
 import { describe, expect, it } from 'vitest'

+import type { WaveformXAxisLabelFormatter, WaveformXAxisLabelFormatterContext } from '../types'
 import {
  formatAnnotationTime,
  formatAxisTime,
-  formatAxisTimeExponent,
  formatEndpointTime,
  formatPlainNumber,
  formatScientificAxisExponent,
  formatScientificAxisLabel,
  formatTooltipNumber,
+  formatTooltipTime,
+  formatXAxisLabel,
+  resolveScientificAxisExponent,
  shouldUseScientificAxisLabel,
 } from './formatters'

 describe('waveform number formatters', () => {
  it('uses the reference Y-axis scientific notation boundaries', () => {
    expect(shouldUseScientificAxisLabel(0)).toBe(false)
-    expect(shouldUseScientificAxisLabel(0.009)).toBe(true)
-    expect(shouldUseScientificAxisLabel(0.01)).toBe(false)
-    expect(shouldUseScientificAxisLabel(99.99)).toBe(false)
-    expect(shouldUseScientificAxisLabel(100)).toBe(true)
+    expect(shouldUseScientificAxisLabel(0.000999)).toBe(true)
+    expect(shouldUseScientificAxisLabel(0.001)).toBe(false)
+    expect(shouldUseScientificAxisLabel(999.999)).toBe(false)
+    expect(shouldUseScientificAxisLabel(1000)).toBe(true)
  })

-  it('shares one separate exponent across an axis', () => {
-    const positiveAxis = { axisMin: 0, axisMax: 254 }
-    expect(formatScientificAxisLabel(127, positiveAxis)).toBe('1.27')
-    expect(formatScientificAxisLabel(254, positiveAxis)).toBe('2.54')
-    expect(formatScientificAxisExponent(0, 254)).toBe('E+02')
+  it('prefixes one shared exponent to the largest visible tick', () => {
+    const positiveAxis = { axisMin: 1000, axisMax: 3000 }
+    expect(formatScientificAxisLabel(1000, positiveAxis)).toBe('1')
+    expect(formatScientificAxisLabel(2000, positiveAxis)).toBe('2')
+    expect(formatScientificAxisLabel(3000, positiveAxis)).toBe('E+03 3')
+    expect(formatScientificAxisLabel(2000, { ...positiveAxis, topTickValue: 2000 })).toBe('E+03 2')
+    expect(formatScientificAxisExponent(1000, 3000)).toBe('E+03')
    expect(formatScientificAxisExponent(0, 1e120)).toBe('E+120')

-    const tinyAxis = { axisMin: 0, axisMax: 0.0002 }
-    expect(formatScientificAxisLabel(0.0001, tinyAxis)).toBe('1.00')
-    expect(formatScientificAxisLabel(0.0002, tinyAxis)).toBe('2.00')
-    expect(formatScientificAxisExponent(0, 0.0002)).toBe('E-04')
-
-    const negativeAxis = { axisMin: -254, axisMax: 0 }
-    expect(formatScientificAxisLabel(-254, negativeAxis)).toBe('-2.54')
-    expect(formatScientificAxisLabel(0, negativeAxis)).toBe('0.00')
-    expect(formatScientificAxisExponent(-254, 0)).toBe('E+02')
+    const tinyAxis = { axisMin: 0.0001, axisMax: 0.0003 }
+    expect(formatScientificAxisLabel(0.0001, tinyAxis)).toBe('1')
+    expect(formatScientificAxisLabel(0.0002, tinyAxis)).toBe('2')
+    expect(formatScientificAxisLabel(0.0003, tinyAxis)).toBe('E-04 3')
+    expect(formatScientificAxisExponent(0.0001, 0.0003)).toBe('E-04')
  })

-  it('keeps plain axes at two decimals and removes negative zero', () => {
-    expect(formatScientificAxisLabel(99.99, { axisMin: 0, axisMax: 99.99 })).toBe('99.99')
-    expect(formatScientificAxisLabel(0.01, { axisMin: 0, axisMax: 0.01 })).toBe('0.01')
-    expect(formatScientificAxisLabel(-0.001, { axisMin: -1, axisMax: 1 })).toBe('0.00')
+  it('derives the exponent from Math.max(axisMin, axisMax)', () => {
+    expect(resolveScientificAxisExponent(-9000, -1000)).toBe(3)
+    expect(resolveScientificAxisExponent(-10_000, 3000)).toBe(3)
+    expect(resolveScientificAxisExponent(-1000, 0)).toBeNull()
+    expect(resolveScientificAxisExponent(0, 0)).toBeNull()
+  })
+
+  it('keeps five significant digits, removes trailing zeroes, and limits decimals to four', () => {
+    expect(formatScientificAxisLabel(123.456, { axisMin: 0, axisMax: 999 })).toBe('123.46')
+    expect(formatScientificAxisLabel(1234.56, { axisMin: 0, axisMax: 9999 })).toBe('1.2346')
+    expect(formatScientificAxisLabel(3000, { axisMin: 1000, axisMax: 3000 })).toBe('E+03 3')
+    expect(formatScientificAxisLabel(-0, { axisMin: -1, axisMax: 1 })).toBe('0')
    expect(formatScientificAxisLabel(Number.NaN)).toBe('NaN')
    expect(formatScientificAxisLabel(Number.POSITIVE_INFINITY)).toBe('Infinity')
    expect(formatScientificAxisExponent(0, 0)).toBeNull()
  })

-  it('formats X-axis ticks and endpoints from the selected display unit', () => {
+  it('formats X-axis ticks and endpoints as complete plain values in the display unit', () => {
    const domain: [number, number] = [0, 1]
-    expect(formatAxisTime(0.5, 'ms', domain)).toBe('0.50')
-    expect(formatEndpointTime(1, domain, 'ms')).toBe('1.00')
-    expect(formatAxisTimeExponent(domain, 'ms')).toBe('E+03')
-    expect(formatAxisTime(0.5, 's', domain)).toBe('0.50')
-    expect(formatEndpointTime(1, domain, 's')).toBe('1.00')
-    expect(formatAxisTimeExponent(domain, 's')).toBeNull()
+    expect(formatAxisTime(0.5004, 'ms', domain)).toBe('500.4')
+    expect(formatEndpointTime(1, domain, 'ms')).toBe('1000')
+    expect(formatAxisTime(0.5, 's', domain)).toBe('0.5')
+    expect(formatEndpointTime(1, domain, 's')).toBe('1')

    const tinyDomain: [number, number] = [0, 0.000001]
-    expect(formatEndpointTime(0.000001, tinyDomain, 's')).toBe('1.00')
-    expect(formatAxisTimeExponent(tinyDomain, 's')).toBe('E-06')
+    expect(formatEndpointTime(0.000001, tinyDomain, 's')).toBe('0.000001')
+    expect(formatAxisTime(-0.000001, 's', tinyDomain)).toBe('-0.000001')
+    expect(formatAxisTime(-0, 's')).toBe('0')
+    expect(formatAxisTime(1e21, 's')).toBe('1000000000000000000000')
+    expect(formatAxisTime(Number.POSITIVE_INFINITY, 's')).toBe('Infinity')
+  })
+
+  it('passes display values and complete source context to X-axis label formatters', () => {
+    const domain: [number, number] = [0.125, 1.875]
+    const formatter: WaveformXAxisLabelFormatter = (value, context) =>
+      `${context.kind}:${value / 10}`
+
+    expect(formatXAxisLabel(0.5, domain, 'ms', 'tick', formatter)).toBe('tick:50')
+    expect(formatXAxisLabel(domain[0], domain, 'ms', 'start', formatter)).toBe('start:12.5')
+    expect(formatXAxisLabel(domain[1], domain, 'ms', 'end', formatter)).toBe('end:187.5')
+
+    let receivedContext: WaveformXAxisLabelFormatterContext | undefined
+    formatXAxisLabel(0.5, domain, 'ms', 'tick', (value, context) => {
+      receivedContext = context
+      return String(value)
+    })
+    expect(receivedContext).toEqual({
+      kind: 'tick',
+      rawValue: 0.5,
+      timeUnit: 'ms',
+      domain: [0.125, 1.875],
+      displayDomain: [125, 1875],
+    })
+
+    expect(() =>
+      formatXAxisLabel(0.5, domain, 's', 'tick', () => {
+        throw new Error('formatter failed')
+      }),
+    ).toThrow('formatter failed')
  })

  it('formats tooltip and raw values for their display contexts', () => {
    expect(formatTooltipNumber(12345.67891)).toBe('12,345.6789')
    expect(formatTooltipNumber(-0)).toBe('0')
    expect(formatTooltipNumber(Number.POSITIVE_INFINITY)).toBe('Infinity')
+    expect(formatTooltipTime(1.234567, 's')).toBe('1.2346')
+    expect(formatTooltipTime(1, 'ms')).toBe('1,000')
    expect(formatPlainNumber(0.0000001)).toBe('0.0000001')
    expect(formatPlainNumber(1e21)).toBe('1000000000000000000000')
    expect(formatPlainNumber(-0)).toBe('0')
--- a/src/utils/formatters.ts
+++ b/src/utils/formatters.ts
@@ -1,22 +1,26 @@
+import type { WaveformXAxisLabelFormatter, WaveformXAxisLabelKind } from '../types'
+
 /**
 * 时间单位类型
 */
 export type TimeUnit = 'ms' | 's'

 export interface ScientificAxisLabelOptions {
+  /** @deprecated Y-axis labels always use five significant digits before localization. */
  precision?: number
  axisMin?: number
  axisMax?: number
-}
-
-/** @deprecated Use ScientificAxisLabelOptions. */
-export type ScientificYAxisLabelOptions = ScientificAxisLabelOptions & {
  topTickValue?: number
 }

-const DEFAULT_Y_AXIS_PRECISION = 2
-const SCIENTIFIC_MIN_ABSOLUTE_VALUE = 0.01
-const SCIENTIFIC_MAX_PLAIN_ABSOLUTE_VALUE = 100
+/** @deprecated Use ScientificAxisLabelOptions. */
+export type ScientificYAxisLabelOptions = ScientificAxisLabelOptions
+
+const SCIENTIFIC_MIN_ABSOLUTE_VALUE = 0.001
+const SCIENTIFIC_MAX_PLAIN_ABSOLUTE_VALUE = 1000
+const Y_AXIS_NUMBER_FORMATTER = new Intl.NumberFormat('zh-CN', {
+  maximumFractionDigits: 4,
+})
 const TOOLTIP_NUMBER_FORMATTER = new Intl.NumberFormat('zh-CN', {
  maximumFractionDigits: 4,
 })
@@ -38,9 +42,10 @@ export function shouldUseScientificAxisLabel(maxAbsoluteValue: number): boolean
 export function resolveScientificAxisExponent(axisMin?: number, axisMax?: number): number | null {
  if (typeof axisMin !== 'number' || typeof axisMax !== 'number') return null

-  const maxAbsoluteValue = Math.max(Math.abs(axisMin), Math.abs(axisMax))
-  return shouldUseScientificAxisLabel(maxAbsoluteValue)
-    ? Math.floor(Math.log10(maxAbsoluteValue))
+  const maxValue = Math.max(axisMin, axisMax)
+  const absoluteMaxValue = Math.abs(maxValue)
+  return shouldUseScientificAxisLabel(absoluteMaxValue)
+    ? Math.floor(Math.log10(absoluteMaxValue))
    : null
 }

@@ -49,6 +54,13 @@ function formatExponent(exponent: number): string {
  return `E${sign}${Math.abs(exponent).toString().padStart(2, '0')}`
 }

+function formatYAxisNumber(value: number): string {
+  if (Object.is(value, -0)) return '0'
+  const roundedValue = value === 0 ? 0 : Number(value.toPrecision(5))
+  const formatted = Y_AXIS_NUMBER_FORMATTER.format(roundedValue)
+  return formatted === '-0' ? '0' : formatted
+}
+
 /** Format a Y-axis tick, sharing one exponent derived from the complete axis domain. */
 export function formatScientificAxisLabel(
  value: number,
@@ -56,10 +68,13 @@ export function formatScientificAxisLabel(
 ): string {
  if (!Number.isFinite(value)) return String(value)

-  const precision = options.precision ?? DEFAULT_Y_AXIS_PRECISION
  const exponent = resolveScientificAxisExponent(options.axisMin, options.axisMax)
  const scaledValue = exponent === null ? value : value / 10 ** exponent
-  return formatFixedNumber(scaledValue, precision)
+  const formattedValue = formatYAxisNumber(scaledValue)
+  const topTickValue = options.topTickValue ?? options.axisMax
+  return exponent !== null && value === topTickValue
+    ? `${formatExponent(exponent)} ${formattedValue}`
+    : formattedValue
 }

 /** Return the shared E-style multiplier for an axis, or null for a plain axis. */
@@ -119,6 +134,26 @@ export function displayTime(value: number, timeUnit: TimeUnit): number {
  return timeUnit === 'ms' ? value * 1000 : value
 }

+/** Format an X-axis value without changing its source coordinate. */
+export function formatXAxisLabel(
+  rawValue: number,
+  domain: [number, number],
+  timeUnit: TimeUnit,
+  kind: WaveformXAxisLabelKind,
+  formatter?: WaveformXAxisLabelFormatter,
+): string {
+  const value = displayTime(rawValue, timeUnit)
+  if (!formatter) return formatPlainNumber(value)
+
+  return formatter(value, {
+    kind,
+    rawValue,
+    timeUnit,
+    domain: [domain[0], domain[1]],
+    displayDomain: [displayTime(domain[0], timeUnit), displayTime(domain[1], timeUnit)],
+  })
+}
+
 /**
 * 计算端点标签的小数位数
 * @param domain 数据域 [最小值, 最大值]
@@ -134,54 +169,33 @@ export function endpointFractionDigits(domain: [number, number], timeUnit: TimeU
 }

 /**
- * 按完整 X 轴显示域格式化端点时间
+ * 将 X 轴端点时间格式化为当前显示单位下的普通十进制文本
 * @param value 时间值（秒）
- * @param domain 数据域
+ * @param _domain 数据域（为保持现有调用签名而保留）
 * @param timeUnit 时间单位
 * @returns 格式化的时间字符串
 */
 export function formatEndpointTime(
  value: number,
-  domain: [number, number],
+  _domain: [number, number],
  timeUnit: TimeUnit,
 ): string {
-  const [axisMin, axisMax] = domain.map((domainValue) => displayTime(domainValue, timeUnit)) as [
-    number,
-    number,
-  ]
-  return formatScientificAxisLabel(displayTime(value, timeUnit), {
-    axisMin,
-    axisMax,
-  })
+  return formatXAxisLabel(value, _domain, timeUnit, 'end')
 }

 /**
- * 按完整 X 轴显示域格式化时间刻度
+ * 将 X 轴时间刻度格式化为当前显示单位下的普通十进制文本
 * @param value 时间值（秒）
 * @param timeUnit 时间单位
+ * @param _domain 数据域（为保持现有调用签名而保留）
 * @returns 格式化的时间字符串
 */
 export function formatAxisTime(
  value: number,
  timeUnit: TimeUnit,
-  domain?: [number, number],
+  _domain?: [number, number],
 ): string {
-  const displayValue = displayTime(value, timeUnit)
-  const displayDomain = domain?.map((domainValue) => displayTime(domainValue, timeUnit)) as
-    [number, number] | undefined
-  return formatScientificAxisLabel(displayValue, {
-    axisMin: displayDomain?.[0],
-    axisMax: displayDomain?.[1],
-  })
-}
-
-/** Return the shared multiplier for an X-axis domain in its selected display unit. */
-export function formatAxisTimeExponent(
-  domain: [number, number],
-  timeUnit: TimeUnit,
-): string | null {
-  const [axisMin, axisMax] = domain.map((value) => displayTime(value, timeUnit)) as [number, number]
-  return formatScientificAxisExponent(axisMin, axisMax)
+  return formatXAxisLabel(value, _domain ?? [value, value], timeUnit, 'tick')
 }

 /**
@@ -191,11 +205,7 @@ export function formatAxisTimeExponent(
 * @returns 格式化的时间字符串
 */
 export function formatTooltipTime(value: number, timeUnit: TimeUnit): string {
-  const displayValue = displayTime(value, timeUnit)
-  return displayValue.toLocaleString('zh-CN', {
-    minimumFractionDigits: 4,
-    maximumFractionDigits: 4,
-  })
+  return formatTooltipNumber(displayTime(value, timeUnit))
 }

 /** Format an annotation X coordinate in the selected display time unit. */
--- a/src/utils/index.ts
+++ b/src/utils/index.ts
@@ -11,7 +11,7 @@ export {
  endpointFractionDigits,
  formatEndpointTime,
  formatAxisTime,
-  formatAxisTimeExponent,
+  formatXAxisLabel,
  formatTooltipTime,
  formatAnnotationTime,
  formatPlainNumber,
--- a/src/views/FixedYDomainDemo.test.ts
+++ b/src/views/FixedYDomainDemo.test.ts
@@ -0,0 +1,44 @@
+import { flushPromises, mount } from '@vue/test-utils'
+import { describe, expect, it } from 'vitest'
+
+import { WaveformChart } from '../components'
+import { routes } from '../router'
+import FixedYDomainDemo from './FixedYDomainDemo.vue'
+
+describe('fixed Y-domain demo route', () => {
+  it('registers the example route', () => {
+    expect(routes).toEqual(
+      expect.arrayContaining([
+        expect.objectContaining({
+          path: '/fixed-y-domain',
+          name: 'fixed-y-domain',
+        }),
+      ]),
+    )
+  })
+
+  it('switches between global, automatic, and per-channel ranges', async () => {
+    const wrapper = mount(FixedYDomainDemo)
+    await flushPromises()
+    const chart = () => wrapper.getComponent(WaveformChart)
+    const modeInputs = wrapper.get('[aria-label="Y 轴范围模式"]').findAll('input[type="radio"]')
+
+    expect(chart().props('yDomain')).toEqual([-80, 80])
+    expect(chart().props('yDomains')).toBeUndefined()
+
+    await modeInputs[0]?.setValue(true)
+    await flushPromises()
+    expect(chart().props('yDomain')).toBeUndefined()
+    expect(chart().props('yDomains')).toBeUndefined()
+
+    await modeInputs[2]?.setValue(true)
+    await flushPromises()
+    expect(chart().props('yDomain')).toBeUndefined()
+    expect(chart().props('yDomains')).toEqual({
+      voltage: [-65, 65],
+      current: [-260, 260],
+    })
+
+    wrapper.unmount()
+  })
+})
--- a/src/views/FixedYDomainDemo.vue
+++ b/src/views/FixedYDomainDemo.vue
@@ -0,0 +1,149 @@
+<script setup lang="ts">
+import { computed, ref } from 'vue'
+import { InputNumber, RadioButton, RadioGroup } from 'ant-design-vue'
+
+import { WaveformChart, type WaveformData } from '../components'
+
+type RangeMode = 'auto' | 'global' | 'channel'
+
+const rangeMode = ref<RangeMode>('global')
+const globalMinimum = ref(-80)
+const globalMaximum = ref(80)
+const voltageMinimum = ref(-65)
+const voltageMaximum = ref(65)
+const currentMinimum = ref(-260)
+const currentMaximum = ref(260)
+
+const chartData: WaveformData = {
+  kind: 'series',
+  series: [
+    {
+      id: 'voltage',
+      name: '电压',
+      unit: 'V',
+      color: '#1677ff',
+      data: {
+        kind: 'points',
+        points: Array.from({ length: 800 }, (_, index) => {
+          const x = index / 80
+          const pulse = index % 240 >= 112 && index % 240 <= 122 ? 58 : 0
+          return { x, y: 48 * Math.sin(x * Math.PI * 1.5) + pulse }
+        }),
+      },
+    },
+    {
+      id: 'current',
+      name: '电流',
+      unit: 'mA',
+      color: '#d4380d',
+      data: {
+        kind: 'points',
+        points: Array.from({ length: 800 }, (_, index) => {
+          const x = index / 80
+          const pulse = index % 300 >= 184 && index % 300 <= 192 ? -210 : 0
+          return { x, y: 185 * Math.cos(x * Math.PI) + pulse }
+        }),
+      },
+    },
+  ],
+}
+
+function orderedDomain(minimum: number, maximum: number): [number, number] | undefined {
+  if (!Number.isFinite(minimum) || !Number.isFinite(maximum) || minimum === maximum) {
+    return undefined
+  }
+  return minimum < maximum ? [minimum, maximum] : [maximum, minimum]
+}
+
+const yDomain = computed<[number, number] | undefined>(() =>
+  rangeMode.value === 'global'
+    ? orderedDomain(globalMinimum.value, globalMaximum.value)
+    : undefined,
+)
+const yDomains = computed<Record<string, [number, number]> | undefined>(() => {
+  if (rangeMode.value !== 'channel') return undefined
+  const voltage = orderedDomain(voltageMinimum.value, voltageMaximum.value)
+  const current = orderedDomain(currentMinimum.value, currentMaximum.value)
+  return {
+    ...(voltage ? { voltage } : {}),
+    ...(current ? { current } : {}),
+  }
+})
+const rangeSummary = computed(() => {
+  if (rangeMode.value === 'auto') return '自动计算'
+  if (rangeMode.value === 'global') {
+    return yDomain.value ? `${yDomain.value[0]} ～ ${yDomain.value[1]}` : '自动计算'
+  }
+  const voltage = yDomains.value?.voltage
+  const current = yDomains.value?.current
+  return `电压 ${voltage?.[0] ?? '-'} ～ ${voltage?.[1] ?? '-'} V · 电流 ${
+    current?.[0] ?? '-'
+  } ～ ${current?.[1] ?? '-'} mA`
+})
+</script>
+
+<template>
+  <main class="fixed-domain-demo">
+    <header class="fixed-domain-demo__toolbar">
+      <div>
+        <h1>固定振幅范围</h1>
+        <p>当前范围：{{ rangeSummary }}</p>
+      </div>
+      <RadioGroup v-model:value="rangeMode" button-style="solid" aria-label="Y 轴范围模式">
+        <RadioButton value="auto">自动</RadioButton>
+        <RadioButton value="global">全局固定</RadioButton>
+        <RadioButton value="channel">按通道固定</RadioButton>
+      </RadioGroup>
+    </header>
+
+    <section class="fixed-domain-demo__range-controls">
+      <template v-if="rangeMode === 'global'">
+        <label>
+          <span>下限</span>
+          <InputNumber v-model:value="globalMinimum" aria-label="全局振幅下限" />
+        </label>
+        <label>
+          <span>上限</span>
+          <InputNumber v-model:value="globalMaximum" aria-label="全局振幅上限" />
+        </label>
+      </template>
+      <template v-else-if="rangeMode === 'channel'">
+        <strong>电压</strong>
+        <label>
+          <span>下限</span>
+          <InputNumber v-model:value="voltageMinimum" aria-label="电压振幅下限" />
+        </label>
+        <label>
+          <span>上限</span>
+          <InputNumber v-model:value="voltageMaximum" aria-label="电压振幅上限" />
+        </label>
+        <strong>电流</strong>
+        <label>
+          <span>下限</span>
+          <InputNumber v-model:value="currentMinimum" aria-label="电流振幅下限" />
+        </label>
+        <label>
+          <span>上限</span>
+          <InputNumber v-model:value="currentMaximum" aria-label="电流振幅上限" />
+        </label>
+      </template>
+      <span v-else class="fixed-domain-demo__auto-state">根据可见数据自动计算</span>
+    </section>
+
+    <section class="fixed-domain-demo__chart">
+      <WaveformChart
+        :data="chartData"
+        :y-domain="yDomain"
+        :y-domains="yDomains"
+        display-mode="independent"
+        :grid="{ rowCount: 2, columnCount: 1, showPagination: false }"
+        :title="{ visible: true, text: '振幅上下限示例', align: 'left' }"
+        :zero-line="{ visible: true, color: '#98a2b3', width: 1, dash: '5 4' }"
+        :legend="{ position: 'top-right', backgroundColor: 'rgba(255,255,255,0.8)' }"
+        x-label="时间（s）"
+        time-unit="s"
+        :show-tooltip="true"
+      />
+    </section>
+  </main>
+</template>
Author	SHA1	Message	Date
李启源	7646bf4907	merge: integrate hybrid domain architecture	2026-08-07 15:59:38 +08:00
李启源	e2725e5569	refactor(chart): introduce hybrid domain architecture	2026-08-07 15:59:26 +08:00
李启源	9eb1f0f137	feat(chart): support configurable plot margins All checks were successful Package component / package (push) Successful in 7m2s Details	2026-08-05 15:16:52 +08:00
李启源	fbf10fdb88	feat(chart): support configurable x-axis labels All checks were successful Package component / package (push) Successful in 4m35s Details	2026-08-05 10:58:40 +08:00
李启源	c5aa3c662a	fix(chart): refine axis number formatting All checks were successful Package component / package (push) Successful in 4m2s Details	2026-08-04 11:28:42 +08:00
李启源	f98c264562	fix(chart): support wheel zoom out All checks were successful Package component / package (push) Successful in 3m50s Details	2026-07-31 12:07:08 +08:00
李启源	979b698156	fix(chart): retain axes in clean view All checks were successful Package component / package (push) Successful in 3m58s Details	2026-07-31 10:27:27 +08:00
李启源	a12002ba11	feat(chart): support fixed y-axis domains All checks were successful Package component / package (push) Successful in 9m22s Details	2026-07-29 15:50:25 +08:00