[OpenLayers-Commits] r11859 - trunk/openlayers/lib/OpenLayers/Renderer

[commits-20090109 at openlayers.org]

Author: tschaub
Date: 2011-04-02 21:58:49 -0700 (Sat, 02 Apr 2011)
New Revision: 11859

Modified:
   trunk/openlayers/lib/OpenLayers/Renderer/Canvas.js
Log:
Simplifying hit detection for external graphics rendered with canvas.  With this change, events within the graphic bounds will be considered hits (previously only events over visible pixels in the external graphic were considered hits).  This simplification gets around same origin limitations.  r=erilem (closes #3238)

Modified: trunk/openlayers/lib/OpenLayers/Renderer/Canvas.js
===================================================================
--- trunk/openlayers/lib/OpenLayers/Renderer/Canvas.js	2011-04-01 23:10:04 UTC (rev 11858)
+++ trunk/openlayers/lib/OpenLayers/Renderer/Canvas.js	2011-04-03 04:58:49 UTC (rev 11859)
@@ -60,8 +60,6 @@
         if (this.hitDetection) {
             this.hitCanvas = document.createElement("canvas");
             this.hitContext = this.hitCanvas.getContext("2d");
-            this.hitGraphicCanvas = document.createElement("canvas");
-            this.hitGraphicContext = this.hitGraphicCanvas.getContext("2d");
         }
     },
     
@@ -113,11 +111,6 @@
             hitCanvas.style.height = size.h + "px";
             hitCanvas.width = size.w;
             hitCanvas.height = size.h;
-            var hitGraphicCanvas = this.hitGraphicCanvas;
-            hitGraphicCanvas.style.width = size.w + "px";
-            hitGraphicCanvas.style.height = size.h + "px";
-            hitGraphicCanvas.width = size.w;
-            hitGraphicCanvas.height = size.h;
         }
     },
     
@@ -232,26 +225,8 @@
                 img, x, y, width, height
             );
             if (this.hitDetection) {
-                var hitGraphicContext = this.hitGraphicContext;
-                var hitContext = this.hitContext;
-                hitGraphicContext.clearRect(0, 0, numRows, numCols);
-                hitGraphicContext.drawImage(
-                    img, 0, 0, width, height
-                );
-                var imagePixels = hitGraphicContext.getImageData(0, 0, width, height).data;
-                var indexData = hitContext.createImageData(width, height);
-                var indexPixels = indexData.data;
-                var pixelIndex;
-                for (var i=0, len=imagePixels.length; i<len; i+=4) {
-                    // look for visible pixels
-                    if (imagePixels[i+3] > 0) {
-                        indexData[i] = red;
-                        indexPixels[i+1] = green;
-                        indexPixels[i+2] = blue;
-                        indexPixels[i+3] = 255;
-                    }
-                }
-                hitContext.putImageData(indexData, x, y);
+                this.setHitContextStyle("fill", featureId);
+                this.hitContext.fillRect(x, y, width, height);
             }
         };