support chunked layerData in regular deserializer

Gruntfile.js

@@ -90,13 +90,15 @@ module.exports = function(grunt) {
         browser : true,
         trailing : true,
         curly : true,
-        globals : {'$':true, 'jQuery' : true, 'pskl':true, 'Events':true, 'Constants':true, 'console' : true, 'module':true, 'require':true, 'Q':true}
+        globals : {'$':true, 'jQuery' : true, 'pskl':true, 'Events':true, 'Constants':true, 'console' : true, 'module':true, 'require':true, 'Q':true, 'Promise': true}
       },
       files: [
+        // Includes
         'Gruntfile.js',
         'package.json',
         'src/js/**/*.js',
-        '!src/js/**/lib/**/*.js' // Exclude lib folder (note the leading !)
+        // Excludes
+        '!src/js/**/lib/**/*.js'
       ]
     },
 

karma.conf.js

@@ -11,7 +11,7 @@ module.exports = function(config) {
 
   // Polyfill for Object.assign (missing in PhantomJS)
   piskelScripts.push('./node_modules/phantomjs-polyfill-object-assign/object-assign-polyfill.js');
-  
+
   config.set({
 
     // base path that will be used to resolve all patterns (eg. files, exclude)
@@ -24,7 +24,9 @@ module.exports = function(config) {
 
 
     // list of files / patterns to load in the browser
-    files: piskelScripts,
+    files: piskelScripts.concat([
+      './node_modules/promise-polyfill/promise.js'
+    ]),
 
 
     // list of files to exclude

package.json

@@ -52,7 +52,8 @@
     "karma-phantomjs-launcher": "0.2.3",
     "load-grunt-tasks": "3.5.0",
     "phantomjs": "2.1.7",
-    "phantomjs-polyfill-object-assign": "0.0.2"
+    "phantomjs-polyfill-object-assign": "0.0.2",
+    "promise-polyfill": "6.0.2"
   },
   "window": {
     "title": "Piskel",

src/js/utils/FrameUtils.js

@@ -177,74 +177,60 @@
     },
 
     /**
-     * Alpha compositing using porter duff algorithm :
-     * http://en.wikipedia.org/wiki/Alpha_compositing
-     * http://keithp.com/~keithp/porterduff/p253-porter.pdf
-     * @param  {String} strColor1 color over
-     * @param  {String} strColor2 color under
-     * @return {String} the composite color
+     * Create a Frame array from an Image object.
+     * Transparent pixels will either be converted to completely opaque or completely transparent pixels.
+     *
+     * @param  {Image} image source image
+     * @param  {Number} frameCount number of frames in the spritesheet
+     * @return {Array<Frame>}
      */
-    mergePixels__ : function (strColor1, strColor2, globalOpacity1) {
-      var col1 = pskl.utils.FrameUtils.toRgba__(strColor1);
-      var col2 = pskl.utils.FrameUtils.toRgba__(strColor2);
-      if (typeof globalOpacity1 == 'number') {
-        col1 = JSON.parse(JSON.stringify(col1));
-        col1.a = globalOpacity1 * col1.a;
+    createFramesFromSpritesheet : function (image, frameCount) {
+      var layout = [];
+      for (var i = 0 ; i < frameCount ; i++) {
+        layout.push([i]);
       }
-      var a = col1.a + col2.a * (1 - col1.a);
-
-      var r = ((col1.r * col1.a + col2.r * col2.a * (1 - col1.a)) / a) | 0;
-      var g = ((col1.g * col1.a + col2.g * col2.a * (1 - col1.a)) / a) | 0;
-      var b = ((col1.b * col1.a + col2.b * col2.a * (1 - col1.a)) / a) | 0;
-
-      return 'rgba(' + r + ',' + g + ',' + b + ',' + a + ')';
+      var chunkFrames = pskl.utils.FrameUtils.createFramesFromChunk(image, layout);
+      return chunkFrames.map(function (chunkFrame) {
+        return chunkFrame.frame;
+      });
     },
 
     /**
-     * Convert a color defined as a string (hex, rgba, rgb, 'TRANSPARENT') to an Object with r,g,b,a properties.
-     * r, g and b are integers between 0 and 255, a is a float between 0 and 1
-     * @param  {String} c color as a string
-     * @return {Object} {r:Number,g:Number,b:Number,a:Number}
+     * Create a Frame array from an Image object.
+     * Transparent pixels will either be converted to completely opaque or completely transparent pixels.
+     *
+     * @param  {Image} image source image
+     * @param  {Array <Array>} layout description of the frame indexes expected to be found in the chunk
+     * @return {Array<Object>} array of objects containing: {index: frame index, frame: frame instance}
      */
-    toRgba__ : function (c) {
-      if (colorCache[c]) {
-        return colorCache[c];
-      }
-      var color, matches;
-      if (c === 'TRANSPARENT') {
-        color = {
-          r : 0,
-          g : 0,
-          b : 0,
-          a : 0
-        };
-      } else if (c.indexOf('rgba(') != -1) {
-        matches = /rgba\((\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*,\s*(1|0\.\d+)\s*\)/.exec(c);
-        color = {
-          r : parseInt(matches[1], 10),
-          g : parseInt(matches[2], 10),
-          b : parseInt(matches[3], 10),
-          a : parseFloat(matches[4])
-        };
-      } else if (c.indexOf('rgb(') != -1) {
-        matches = /rgb\((\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)/.exec(c);
-        color = {
-          r : parseInt(matches[1], 10),
-          g : parseInt(matches[2], 10),
-          b : parseInt(matches[3], 10),
-          a : 1
-        };
-      } else {
-        matches = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(c);
-        color = {
-          r : parseInt(matches[1], 16),
-          g : parseInt(matches[2], 16),
-          b : parseInt(matches[3], 16),
-          a : 1
-        };
+    createFramesFromChunk : function (image, layout) {
+      var width = image.width;
+      var height = image.height;
+
+      // Recalculate the expected frame dimensions from the layout information
+      var frameWidth = width / layout.length;
+      var frameHeight = height / layout[0].length;
+
+      // Create a canvas adapted to the image size
+      var canvas = pskl.utils.CanvasUtils.createCanvas(frameWidth, frameHeight);
+      var context = canvas.getContext('2d');
+
+      // Draw the zoomed-up pixels to a different canvas context
+      var chunkFrames = [];
+      for (var i = 0 ; i < layout.length ; i++) {
+        var row = layout[i];
+        for (var j = 0 ; j < row.length ; j++) {
+          context.clearRect(0, 0 , frameWidth, frameHeight);
+          context.drawImage(image, frameWidth * i, frameHeight * j, frameWidth, frameHeight, 0, 0, frameWidth, height);
+          var frame = pskl.utils.FrameUtils.createFromCanvas(canvas, 0, 0, frameWidth, height);
+          chunkFrames.push({
+            index : layout[i][j],
+            frame : frame
+          });
+        }
       }
-      colorCache[c] = color;
-      return color;
+
+      return chunkFrames;
     }
   };
 })();

src/js/utils/LayerUtils.js

@@ -2,34 +2,6 @@
   var ns = $.namespace('pskl.utils');
 
   ns.LayerUtils = {
-    /**
-     * Create a Frame array from an Image object.
-     * Transparent pixels will either be converted to completely opaque or completely transparent pixels.
-     * TODO : move to FrameUtils
-     *
-     * @param  {Image} image source image
-     * @param  {Number} frameCount number of frames in the spritesheet
-     * @return {Array<Frame>}
-     */
-    createFramesFromSpritesheet : function (image, frameCount) {
-      var width = image.width;
-      var height = image.height;
-      var frameWidth = width / frameCount;
-
-      var canvas = pskl.utils.CanvasUtils.createCanvas(frameWidth, height);
-      var context = canvas.getContext('2d');
-
-      // Draw the zoomed-up pixels to a different canvas context
-      var frames = [];
-      for (var i = 0 ; i < frameCount ; i++) {
-        context.clearRect(0, 0 , frameWidth, height);
-        context.drawImage(image, frameWidth * i, 0, frameWidth, height, 0, 0, frameWidth, height);
-        var frame = pskl.utils.FrameUtils.createFromCanvas(canvas, 0, 0, frameWidth, height);
-        frames.push(frame);
-      }
-      return frames;
-    },
-
     mergeLayers : function (layerA, layerB) {
       var framesA = layerA.getFrames();
       var framesB = layerB.getFrames();

src/js/utils/serialization/Deserializer.js

@@ -31,52 +31,49 @@
     this.piskel_ = new pskl.model.Piskel(piskelData.width, piskelData.height, piskelData.fps, descriptor);
 
     this.layersToLoad_ = piskelData.layers.length;
-    if (piskelData.expanded) {
-      piskelData.layers.forEach(this.loadExpandedLayer.bind(this));
-    } else {
-      piskelData.layers.forEach(this.deserializeLayer.bind(this));
-    }
+    piskelData.layers.forEach(this.deserializeLayer.bind(this));
   };
 
   ns.Deserializer.prototype.deserializeLayer = function (layerString, index) {
     var layerData = JSON.parse(layerString);
     var layer = new pskl.model.Layer(layerData.name);
     layer.setOpacity(layerData.opacity);
 
-    // 1 - create an image to load the base64PNG representing the layer
-    var base64PNG = layerData.base64PNG;
-    var image = new Image();
-
-    // 2 - attach the onload callback that will be triggered asynchronously
-    image.onload = function () {
-      // 5 - extract the frames from the loaded image
-      var frames = pskl.utils.LayerUtils.createFramesFromSpritesheet(image, layerData.frameCount);
-      // 6 - add each image to the layer
-      this.addFramesToLayer(frames, layer, index);
-    }.bind(this);
+    // Backward compatibility: if the layerData is not chunked but contains a single base64PNG,
+    // create a fake chunk, expected to represent all frames side-by-side.
+    if (typeof layerData.chunks === 'undefined' && layerData.base64PNG) {
+      this.normalizeLayerData_(layerData);
+    }
 
-    // 3 - set the source of the image
-    image.src = base64PNG;
-    return layer;
-  };
+    var chunks = layerData.chunks;
 
-  ns.Deserializer.prototype.loadExpandedLayer = function (layerData, index) {
-    var width = this.piskel_.getWidth();
-    var height = this.piskel_.getHeight();
-    var layer = new pskl.model.Layer(layerData.name);
-    layer.setOpacity(layerData.opacity);
-    var frames = layerData.grids.map(function (grid) {
-      return pskl.model.Frame.fromPixelGrid(grid, width, height);
+    // Prepare a frames array to store frame objects extracted from the chunks.
+    var frames = [];
+    Promise.all(chunks.map(function (chunk) {
+      // Create a promise for each chunk.
+      return new Promise(function (resolve, reject) {
+        var image = new Image();
+        // Load the chunk image in an Image object.
+        image.onload = function () {
+          // extract the chunkFrames from the chunk image
+          var chunkFrames = pskl.utils.FrameUtils.createFramesFromChunk(image, chunk.layout);
+          // add each image to the frames array, at the extracted index
+          chunkFrames.forEach(function (chunkFrame) {
+            frames[chunkFrame.index] = chunkFrame.frame;
+          });
+          resolve();
+        };
+        image.src = chunk.base64PNG;
+      });
+    })).then(function () {
+      frames.forEach(layer.addFrame.bind(layer));
+      this.layers_[index] = layer;
+      this.onLayerLoaded_();
+    }.bind(this)).catch(function () {
+      console.error('Failed to deserialize layer');
     });
-    this.addFramesToLayer(frames, layer, index);
-    return layer;
-  };
 
-  ns.Deserializer.prototype.addFramesToLayer = function (frames, layer, index) {
-    frames.forEach(layer.addFrame.bind(layer));
-
-    this.layers_[index] = layer;
-    this.onLayerLoaded_();
+    return layer;
   };
 
   ns.Deserializer.prototype.onLayerLoaded_ = function () {
@@ -88,4 +85,19 @@
       this.callback_(this.piskel_);
     }
   };
+
+  /**
+   * Backward comptibility only. Create a chunk for layerData objects that only contain
+   * an single base64PNG without chunk/layout information.
+   */
+  ns.Deserializer.prototype.normalizeLayerData_ = function (layerData) {
+    var layout = [];
+    for (var i = 0 ; i < layerData.frameCount ; i++) {
+      layout.push([i]);
+    }
+    layerData.chunks = [{
+      base64PNG : layerData.base64PNG,
+      layout : layout
+    }];
+  };
 })();

src/js/utils/serialization/arraybuffer/ArrayBufferDeserializer.js

@@ -96,7 +96,7 @@
       var loadLayerImage = function(layer, cb) {
         var image = new Image();
         image.onload = function() {
-          var frames = pskl.utils.LayerUtils.createFramesFromSpritesheet(this, layer.frameCount);
+          var frames = pskl.utils.FrameUtils.createFramesFromSpritesheet(this, layer.frameCount);
           frames.forEach(function (frame) {
             layer.model.addFrame(frame);
           });

src/js/utils/serialization/arraybuffer/ArrayBufferSerializer.js

@@ -85,7 +85,7 @@
       return bytes;
     },
 
-    serialize : function (piskel, expanded) {
+    serialize : function (piskel) {
       var i;
       var j;
       var layers;

test/js/utils/FrameUtilsTest.js

@@ -86,7 +86,7 @@ describe("FrameUtils suite", function() {
     var spritesheet = pskl.utils.FrameUtils.toImage(frame);
 
     // split the spritesheet by 4
-    var frames = pskl.utils.LayerUtils.createFramesFromSpritesheet(spritesheet, 4);
+    var frames = pskl.utils.FrameUtils.createFramesFromSpritesheet(spritesheet, 4);
 
     // expect 4 frames of 1x2
     expect(frames.length).toBe(4);