fixed #2712 - a costume-shrinkWrap edgecase bug

thanks, @brianharvey, for reporting it!

HISTORY.md

@@ -2,8 +2,13 @@
 
 ## in development:
 
+* **Notable Fixes:**
+    * fixed a costume-shrinkWrap edgecase bug, thanks, Brian, for reporting it!
+
+
 ### 2020-11-09
 * new dev version
+* objects: fixed #2712 - a costume-shrinkWrap edgecase bug, thanks, Brian, for reporting it!
 
 ## 6.3.1
 * **Notable Fixes:**

snap.html

@@ -10,7 +10,7 @@
         <script src="src/widgets.js?version=2020-10-06"></script>
         <script src="src/blocks.js?version=2020-11-02"></script>
         <script src="src/threads.js?version=2020-11-02"></script>
-        <script src="src/objects.js?version=2020-11-05"></script>
+        <script src="src/objects.js?version=2020-11-09"></script>
         <script src="src/gui.js?version=2020-11-09"></script>
         <script src="src/paint.js?version=2020-05-17"></script>
         <script src="src/lists.js?version=2020-07-01"></script>

src/objects.js

@@ -84,7 +84,7 @@ BlockEditorMorph, BlockDialogMorph, PrototypeHatBlockMorph,  BooleanSlotMorph,
 localize, TableMorph, TableFrameMorph, normalizeCanvas, VectorPaintEditorMorph,
 AlignmentMorph, Process, WorldMap, copyCanvas, useBlurredShadows*/
 
-modules.objects = '2020-November-05';
+modules.objects = '2020-November-09';
 
 var SpriteMorph;
 var StageMorph;
@@ -9689,8 +9689,8 @@ Costume.prototype.canvasBoundingBox = function (pic) {
     }
 
     function getLeft() {
-        for (col = 0; col <= w; col += 1) {
-            for (row = 0; row <= h; row += 1) {
+        for (col = 0; col < w; col += 1) {
+            for (row = 0; row < h; row += 1) {
                 if (getAlpha(col, row)) {
                     return col;
                 }
@@ -9700,8 +9700,8 @@ Costume.prototype.canvasBoundingBox = function (pic) {
     }
 
     function getTop() {
-        for (row = 0; row <= h; row += 1) {
-            for (col = 0; col <= w; col += 1) {
+        for (row = 0; row < h; row += 1) {
+            for (col = 0; col < w; col += 1) {
                 if (getAlpha(col, row)) {
                     return row;
                 }
@@ -9711,8 +9711,8 @@ Costume.prototype.canvasBoundingBox = function (pic) {
     }
 
     function getRight() {
-        for (col = w; col >= 0; col -= 1) {
-            for (row = h; row >= 0; row -= 1) {
+        for (col = w - 1; col >= 0; col -= 1) {
+            for (row = h - 1; row >= 0; row -= 1) {
                 if (getAlpha(col, row)) {
                     return Math.min(col + 1, w);
                 }
@@ -9722,8 +9722,8 @@ Costume.prototype.canvasBoundingBox = function (pic) {
     }
 
     function getBottom() {
-        for (row = h; row >= 0; row -= 1) {
-            for (col = w; col >= 0; col -= 1) {
+        for (row = h - 1; row >= 0; row -= 1) {
+            for (col = w - 1; col >= 0; col -= 1) {
                 if (getAlpha(col, row)) {
                     return Math.min(row + 1, h);
                 }