add maxAnchorSize for drawing ployline

modules/plot/Plot.js

@@ -160,8 +160,11 @@ class Plot {
     if (this._currentWorker) {
       this._currentWorker.stop()
     }
+    let maxAnchorSize = style?.maxAnchorSize || 999
+    style && delete style['maxAnchorSize']
     this._currentWorker = this._createDrawWorker(type, style)?.start(this, {
       ...this._options,
+      maxAnchorSize: maxAnchorSize,
       onDrawStop: callback,
       clampToModel: clampToModel ?? this._options.clampToModel
     })

modules/plot/draw/DrawPolyline.js

@@ -61,8 +61,13 @@ class DrawPolyline extends Draw {
    * @private
    */
   _onDrawAnchor(position) {
+    let len = this._positions.length
     this._positions.push(position)
     this.drawTool.fire(PlotEventType.CREATE_ANCHOR, { position })
+    if (len >= this._options.maxAnchorSize) {
+      this._positions.pop()
+      this.drawTool.fire(PlotEventType.DRAW_STOP)
+    }
   }
 }
 

modules/tools/DrawTool.js

@@ -14,7 +14,8 @@ const DEF_OPTS = {
   icon_center: IMG_CIRCLE_YELLOW,
   icon_anchor: IMG_CIRCLE_RED,
   icon_size: [12, 12],
-  clampToModel: false
+  clampToModel: false,
+  maxAnchorSize: 999
 }
 
 class DrawTool {