update CHANGELOG with new version

src/shapes/Transformer.ts

@@ -662,14 +662,20 @@ export class Transformer extends Group {
     stage.setPointersPositions(e);
 
     const pp = stage.getPointerPosition();
-    var newNodePos = {
+    let newNodePos = {
       x: pp.x - this._anchorDragOffset.x,
       y: pp.y - this._anchorDragOffset.y,
     };
     const oldAbs = anchorNode.getAbsolutePosition();
+
+    if (this.anchorDragBoundFunc()) {
+      newNodePos = this.anchorDragBoundFunc()(oldAbs, newNodePos, e);
+    }
     anchorNode.setAbsolutePosition(newNodePos);
     const newAbs = anchorNode.getAbsolutePosition();
 
+    // console.log(oldAbs, newNodePos, newAbs);
+
     if (oldAbs.x === newAbs.x && oldAbs.y === newAbs.y) {
       return;
     }
@@ -1235,6 +1241,10 @@ export class Transformer extends Group {
   flipEnabled: GetSet<boolean, this>;
   ignoreStroke: GetSet<boolean, this>;
   boundBoxFunc: GetSet<(oldBox: Box, newBox: Box) => Box, this>;
+  anchorDragBoundFunc: GetSet<
+    (oldPos: Vector2d, newPos: Vector2d, e: MouseEvent) => Box,
+    this
+  >;
   shouldOverdrawWholeArea: GetSet<boolean, this>;
   useSingleNodeRotation: GetSet<boolean, this>;
 }
@@ -1641,6 +1651,26 @@ Factory.addGetterSetter(Transformer, 'nodes');
  */
 Factory.addGetterSetter(Transformer, 'boundBoxFunc');
 
+/**
+ * get/set dragging func for transformer anchors
+ * @name Konva.Transformer#anchorDragBoundFunc
+ * @method
+ * @param {Function} func
+ * @returns {Function}
+ * @example
+ * // get
+ * var anchorDragBoundFunc = transformer.anchorDragBoundFunc();
+ *
+ * // set
+ * transformer.anchorDragBoundFunc(function(oldAbsPos, newAbsPos, event) {
+ *  return {
+ *   x: 0,
+ *   y: newAbsolutePosition.y
+ *  }
+ * });
+ */
+Factory.addGetterSetter(Transformer, 'anchorDragBoundFunc');
+
 /**
  * using this setting you can drag transformer group by dragging empty space between attached nodes
  * shouldOverdrawWholeArea = true may temporary disable all events on attached nodes