Improve coordinate frames, see #95

js/least-squares-regression/model/DataPoint.ts

@@ -57,7 +57,7 @@ export default class DataPoint {
   /**
    * Function that animates the DataPoint back to the bucket.
    */
-  public animate(): void {
+  public animateBackToBucket(): void {
     this.animatingProperty.set( true );
 
     const distance = this.positionProperty.initialValue.distance( this.positionProperty.value );

js/least-squares-regression/model/LeastSquaresRegressionModel.ts

@@ -187,7 +187,7 @@ export default class LeastSquaresRegressionModel {
    */
   public returnAllDataPointsToBucket(): void {
     this.dataPoints.forEach( dataPoint => {
-      dataPoint.animate();
+      dataPoint.animateBackToBucket();
     } );
   }
 
@@ -210,7 +210,7 @@ export default class LeastSquaresRegressionModel {
       const isOnGraph = this.graph.isDataPointPositionOverlappingGraph( dataPoint.positionProperty.value );
       if ( !isOnGraph && !userControlled ) {
         // return the dataPoint to the bucket
-        dataPoint.animate();
+        dataPoint.animateBackToBucket();
       }
     };
 

js/least-squares-regression/view/DataPointCreatorNode.ts

@@ -45,10 +45,12 @@ export default class DataPointCreatorNode extends Node {
     this.addInputListener( DragListener.createForwardingListener( event => {
 
       // Determine the initial position (set to be one circle radius above the pointer point)
-      const initialPosition = event.pointer.point;
+      const viewPosition = this.globalToParentPoint( event.pointer.point );
 
       // Create and add the new model element.
-      const dataPoint = new DataPoint( modelViewTransform.viewToModelPosition( initialPosition ) );
+      const modelPosition = modelViewTransform.viewToModelPosition( viewPosition );
+
+      const dataPoint = new DataPoint( modelPosition );
       dataPoint.userControlledProperty.set( true );
       const dynamicDataPointNode = addDataPointToModel( dataPoint );