docs: update the scroll-canvas docs

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - feat: scroll-canvas behavior;
 - feat: iconfont for node icon;
+- feat: percentage of scalable range for drag-canvas;
 - fix: missing brushStyle in type ModeOption;
 - fix: the comboId remains in the node after uncombo(), closes #2801;
 - fix: disappearing edges when combos are expanded/collapsed, closes #2798;

packages/site/docs/manual/middle/states/defaultBehavior.en.md

@@ -106,7 +106,10 @@ const graph = new G6.Graph({
   - `direction`: The direction of dragging that is allowed. Options: `'x'`, `'y'`, `'both'`. `'both'` by default;
   - `enableOptimize`: whether enable optimization, `false` by default. `enableOptimize: true` means hiding all edges and the shapes beside keyShapes of nodes while dragging canvas;
   - `shouldBegin(e)`: Whether allow the behavior happen on the current item (e.item);
-  - `scalableRange`: scaleable range when drag canvas, `zero` by default;
+  - `scalableRange`: scalable range when drag canvas, `zero` by default. -1 to 1 means the scalable percentage of the viewport; the image bellow illustrate the situation when it is smaller than -1 or bigger than 1: 
+
+  <img src='https://gw.alipayobjects.com/mdn/rms_f8c6a0/afts/img/A*IFfoS67_HssAAAAAAAAAAAAAARQnAQ' width='650' alt="" />
+
   - `allowDragOnItem`: whether response when the users drag on items(node/edge/combo), `false` by default;
 - Related timing events:
   - `canvas:dragstart`: Triggered when drag start. Listened by `graph.on('canvas:dragstart', e => {...})`;
@@ -142,6 +145,51 @@ const graph = new G6.Graph({
 
 The canvas can be dragged along x direction only.<br /><img src='https://gw.alipayobjects.com/mdn/rms_f8c6a0/afts/img/A*54yxRrW1A7sAAAAAAAAAAABkARQnAQ' width=400 alt='img'/>
 
+
+### scroll-canvas
+
+- Description: Scroll the canvas by wheeling, *supported after v4.2.6*;
+- Configurations:
+  - `type: 'scroll-canvas'`;
+  - `direction`: The direction of dragging that is allowed. Options: `'x'`, `'y'`, `'both'`. `'both'` by default;
+  - `enableOptimize`: whether enable optimization, `false` by default. `enableOptimize: true` means hiding all edges and the shapes beside keyShapes of nodes while dragging canvas;
+  - `zoomKey`: switch to zooming while pressing the key and wheeling. Options: `'shift'`, `'ctrl'`, `'alt'`, `'control'`;
+  - `scalableRange`: scalable range when drag canvas, `zero` by default. -1 to 1 means the scalable percentage of the viewport; the image bellow illustrate the situation when it is smaller than -1 or bigger than 1: 
+
+  <img src='https://gw.alipayobjects.com/mdn/rms_f8c6a0/afts/img/A*IFfoS67_HssAAAAAAAAAAAAAARQnAQ' width='650' alt="" />
+
+- Related timing events:
+  - `wheel`: Triggered when wheeling. Listened by `graph.on('wheel', e => {...})`.
+
+**Using Default Configuration**
+
+```javascript
+const graph = new G6.Graph({
+  modes: {
+    default: ['drag-canvas'],
+  },
+});
+```
+
+By default, the x and y directions are both allowed.
+
+**Using Customized Configuration**
+
+```javascript
+const graph = new G6.Graph({
+  modes: {
+    default: [
+      {
+        type: 'drag-canvas',
+        direction: 'x',
+      },
+    ],
+  },
+});
+```
+
+The canvas can be dragged along x direction only.<br /><img src='https://gw.alipayobjects.com/mdn/rms_f8c6a0/afts/img/A*54yxRrW1A7sAAAAAAAAAAABkARQnAQ' width=400 alt='img'/>
+
 ### zoom-canvas
 
 - Description: Zoom the canvas;
@@ -163,6 +211,7 @@ The canvas can be dragged along x direction only.<br /><img src='https://gw.alip
 
 **Tips: Assign values for `minZoom` and  `maxZoom` on the graph to limit the zooming ratio.**
 
+
 ### drag-node
 
 - Description: Allows users drag nodes;

packages/site/docs/manual/middle/states/defaultBehavior.zh.md

@@ -108,7 +108,7 @@ const graph = new G6.Graph({
   - `enableOptimize`：是否开启优化，开启后拖动画布过程中隐藏所有的边及节点上非 keyShape 部分，默认关闭；
   - `shouldBegin(e)`：是否允许触发该操作；
   - `allowDragOnItem`：是否允许用户在节点/边/ combo 上拖拽时响应，默认为 false；
-  - `scalableRange`：拖动 canvas 可扩展的范围，默认为 0，取值为正和负数时的效果如下图所示。
+  - `scalableRange`：拖动 canvas 可扩展的范围，默认为 0，值为 -1 ～ 1 代表可超出视口的范围的比例值（相对于视口大小）。值小于 -1 或大于 1 时，为正和负数时的效果如下图所示。
 
   <img src='https://gw.alipayobjects.com/mdn/rms_f8c6a0/afts/img/A*IFfoS67_HssAAAAAAAAAAAAAARQnAQ' width='650' />
 
@@ -146,6 +146,53 @@ const graph = new G6.Graph({
 
 此时只能在 x 方向上面拖动，y 方向上不允许拖动。<br /><img src='https://gw.alipayobjects.com/mdn/rms_f8c6a0/afts/img/A*54yxRrW1A7sAAAAAAAAAAABkARQnAQ' width=400 alt='img'/>
 
+
+### scroll-canvas
+
+- 含义：滚轮滚动画布，*v4.2.6 起支持*；
+- 配置项：
+
+  - `type: 'scroll-canvas'`；
+  - `direction`：允许拖拽方向，支持`'x'`，`'y'`，`'both'`，默认方向为 `'both'`；
+  - `enableOptimize`：是否开启优化，开启后拖动画布过程中隐藏所有的边及节点上非 keyShape 部分，默认关闭；
+  - `zoomKey`：切换为滚动缩放的键盘按钮，按住该键并滚动滚轮，则切换为滚轮缩放画布，可选项为：`'shift'`，`'ctrl'`，`'alt'`，`'control'`；
+  - `scalableRange`：拖动 canvas 可扩展的范围，默认为 0，值为 -1 ～ 1 代表可超出视口的范围的比例值（相对于视口大小）。值小于 -1 或大于 1 时，为正和负数时的效果如下图所示。
+
+  <img src='https://gw.alipayobjects.com/mdn/rms_f8c6a0/afts/img/A*IFfoS67_HssAAAAAAAAAAAAAARQnAQ' width='650' alt="" />
+
+- 相关时机事件：
+  - `onWheel`：滚轮滚动时触发，使用 `graph.on('onWheel', e => {...})` 监听。
+
+**使用默认配置**
+
+```javascript
+const graph = new G6.Graph({
+  modes: {
+    default: ['scroll-canvas'],
+  },
+});
+```
+
+默认配置下，可以在 x 和 y 两个方向上滚动画布。
+
+**使用自定义参数**
+
+```javascript
+const graph = new G6.Graph({
+  modes: {
+    default: [
+      {
+        type: 'scroll-canvas',
+        direction: 'x',
+      },
+    ],
+  },
+});
+```
+
+此时只能在 x 方向上面滚动，y 方向上不允许滚动。<br /><img src='https://gw.alipayobjects.com/mdn/rms_f8c6a0/afts/img/A*54yxRrW1A7sAAAAAAAAAAABkARQnAQ' width=400 alt='img'/>
+
+
 ### zoom-canvas
 
 - 含义：缩放画布；

packages/site/examples/algorithm/algoDemos/demo/louvain.js

@@ -34,7 +34,7 @@ const graph = new G6.Graph({
     default: ['drag-canvas', 'drag-node', 'zoom-canvas'],
   },
   layout: {
-    // type: 'gForce',
+    type: 'gForce',
     minMovement: 0.1,
   },
 });