speed-up talk bubble positioning by 5x

HISTORY.md

@@ -1,12 +1,15 @@
 # Snap! (BYOB) History
 
 ## in development:
+* **Notable Changes:**
+    * speed-up  talk bubble positioning by 5x
 * **Notable Fixes:**
     * work around a floating point precision glitch in "ray length"
 
 ### 2021-04-17
 * new dev version
 * threads: worked around a floating point precision glitch in "ray length"
+* objects: speed-up  talk bubble positioning by 5x
 
 ## 6.7.4
 * **Notable Fixes:**

snap.html

@@ -10,7 +10,7 @@
         <script src="src/widgets.js?version=2021-01-05"></script>
         <script src="src/blocks.js?version=2021-02-27"></script>
         <script src="src/threads.js?version=2021-04-17"></script>
-        <script src="src/objects.js?version=2021-04-09"></script>
+        <script src="src/objects.js?version=2021-04-17"></script>
         <script src="src/gui.js?version=2021-04-17"></script>
         <script src="src/paint.js?version=2020-05-17"></script>
         <script src="src/lists.js?version=2021-03-15"></script>

src/objects.js

@@ -84,7 +84,7 @@ BlockEditorMorph, BlockDialogMorph, PrototypeHatBlockMorph,  BooleanSlotMorph,
 localize, TableMorph, TableFrameMorph, normalizeCanvas, VectorPaintEditorMorph,
 AlignmentMorph, Process, WorldMap, copyCanvas, useBlurredShadows*/
 
-modules.objects = '2021-April-09';
+modules.objects = '2021-April-17';
 
 var SpriteMorph;
 var StageMorph;
@@ -5377,7 +5377,12 @@ SpriteMorph.prototype.positionTalkBubble = function () {
     var stage = this.parentThatIsA(StageMorph),
         stageScale = stage ? stage.scale : 1,
         bubble = this.talkBubble(),
-        middle = this.center().y;
+        middle = this.center().y,
+        // step = new Point(-10, 10);
+        step = this.extent().divideBy(10)
+            .max(new Point(5, 5).scaleBy(stageScale))
+            .multiplyBy(new Point(-1, 1));
+
     if (!bubble) {return null; }
     bubble.show();
     if (!bubble.isPointingRight) {
@@ -5388,8 +5393,9 @@ SpriteMorph.prototype.positionTalkBubble = function () {
     bubble.setLeft(this.right());
     bubble.setBottom(this.top());
     while (!this.isTouching(bubble) && bubble.bottom() < middle) {
-        bubble.moveBy(new Point(-1, 1).scaleBy(stageScale));
+        bubble.moveBy(step);
     }
+    bubble.moveBy(step.mirror());
     if (!stage) {return null; }
     if (bubble.right() > stage.right()) {
         bubble.isPointingRight = false;