merged from master

js/utils/FrameUtils.js

@@ -91,6 +91,62 @@
       }
       colorCache[c] = color;
       return color;
+    },
+
+    /*
+     * Create a pskl.model.Frame from an Image object.
+     * Transparent pixels will either be converted to completely opaque or completely transparent pixels.
+     * @param  {Image} image source image
+     * @return {pskl.model.Frame} corresponding frame
+     */
+    createFromImage : function (image) {
+      var w = image.width,
+        h = image.height;
+      var canvas = pskl.CanvasUtils.createCanvas(w, h);
+      var context = canvas.getContext('2d');
+
+      context.drawImage(image, 0,0,w,h,0,0,w,h);
+      var imgData = context.getImageData(0,0,w,h).data;
+      // Draw the zoomed-up pixels to a different canvas context
+      var frame = [];
+      for (var x=0;x<image.width;++x){
+        frame[x] = [];
+        for (var y=0;y<image.height;++y){
+          // Find the starting index in the one-dimensional image data
+          var i = (y*image.width + x)*4;
+          var r = imgData[i  ];
+          var g = imgData[i+1];
+          var b = imgData[i+2];
+          var a = imgData[i+3];
+          if (a < 125) {
+            frame[x][y] = "TRANSPARENT";
+          } else {
+            frame[x][y] = this.rgbToHex(r,g,b);
+          }
+        }
+      }
+      return frame;
+    },
+
+    /**
+     * Convert a rgb(Number, Number, Number) color to hexadecimal representation
+     * @param  {Number} r red value, between 0 and 255
+     * @param  {Number} g green value, between 0 and 255
+     * @param  {Number} b blue value, between 0 and 255
+     * @return {String} hex representation of the color '#ABCDEF'
+     */
+    rgbToHex : function (r, g, b) {
+      return "#" + this.componentToHex(r) + this.componentToHex(g) + this.componentToHex(b);
+    },
+
+    /**
+     * Convert a color component (as a Number between 0 and 255) to its string hexa representation
+     * @param  {Number} c component value, between 0 and 255
+     * @return {String} eg. '0A'
+     */
+    componentToHex : function (c) {
+      var hex = c.toString(16);
+      return hex.length == 1 ? "0" + hex : hex;
     }
   };
 })();