Forgot 2 files !

js/rendering/layer/LayersRenderer.js

@@ -0,0 +1,58 @@
+(function () {
+  var ns = $.namespace('pskl.rendering.layer');
+
+  ns.LayersRenderer = function (container, renderingOptions, piskelController) {
+    pskl.rendering.CompositeRenderer.call(this);
+
+    this.piskelController = piskelController;
+
+    this.belowRenderer = new pskl.rendering.frame.CachedFrameRenderer(container, renderingOptions, ["layers-canvas", "layers-below-canvas"]);
+    this.aboveRenderer = new pskl.rendering.frame.CachedFrameRenderer(container, renderingOptions, ["layers-canvas", "layers-above-canvas"]);
+
+    this.add(this.belowRenderer);
+    this.add(this.aboveRenderer);
+
+    this.serializedRendering = '';
+  };
+
+  pskl.utils.inherit(pskl.rendering.layer.LayersRenderer, pskl.rendering.CompositeRenderer);
+
+  ns.LayersRenderer.prototype.render = function () {
+    var layers = this.piskelController.getLayers();
+    var currentFrameIndex = this.piskelController.currentFrameIndex;
+    var currentLayerIndex = this.piskelController.currentLayerIndex;
+
+    var serializedRendering = [
+      this.getZoom(),
+      currentFrameIndex,
+      currentLayerIndex,
+      layers.length
+    ].join("-");
+
+    if (this.serializedRendering != serializedRendering) {
+      this.serializedRendering = serializedRendering;
+
+      this.clear();
+
+      var downLayers = layers.slice(0, currentLayerIndex);
+      if (downLayers.length > 0) {
+        var downFrame = this.getFrameForLayersAt_(currentFrameIndex, downLayers);
+        this.belowRenderer.render(downFrame);
+      }
+
+      var upLayers = layers.slice(currentLayerIndex + 1, layers.length);
+      if (upLayers.length > 0) {
+        var upFrame = this.getFrameForLayersAt_(currentFrameIndex, upLayers);
+        this.aboveRenderer.render(upFrame);
+      }
+
+    }
+  };
+
+  ns.LayersRenderer.prototype.getFrameForLayersAt_ = function (frameIndex, layers) {
+    var frames = layers.map(function (l) {
+      return l.getFrameAt(frameIndex);
+    });
+    return pskl.utils.FrameUtils.merge(frames);
+  };
+})();