Feature : merge layers

Added feature to merge a layer with the layer below
Done at #jsconfeu2014 :)

New icon in icons : merge-icon.png
TODO : reorder the icons folder, it's waaaaaaay too messy !!

src/js/controller/LayersListController.js

@@ -67,6 +67,9 @@
     } else if (el.classList.contains('edit-icon')) {
       index = el.parentNode.dataset.layerIndex;
       this.renameLayerAt_(index);
+    } else if (el.classList.contains('merge-icon')) {
+      index = el.parentNode.dataset.layerIndex;
+      this.mergeDownLayerAt_(index);
     }
   };
 
@@ -79,6 +82,11 @@
     }
   };
 
+  ns.LayersListController.prototype.mergeDownLayerAt_ = function (index) {
+    this.piskelController.mergeDownLayerAt(index);
+    this.renderLayerList_();
+  };
+
   ns.LayersListController.prototype.onButtonClick_ = function (button) {
     var action = button.getAttribute('data-action');
     if (action == 'up') {

src/js/controller/piskel/PiskelController.js

@@ -205,6 +205,18 @@
     }
   };
 
+  ns.PiskelController.prototype.mergeDownLayerAt = function (index) {
+    var layer = this.getLayerByIndex(index);
+    var downLayer = this.getLayerByIndex(index-1);
+    if (layer && downLayer) {
+      var mergedLayer = pskl.utils.LayerUtils.mergeLayers(layer, downLayer);
+      this.removeLayerAt(index);
+      this.piskel.addLayerAt(mergedLayer, index);
+      this.removeLayerAt(index-1);
+      this.selectLayer(mergedLayer);
+    }
+  };
+
   ns.PiskelController.prototype.generateLayerName_ = function () {
     var name = "Layer " + this.layerIdCounter;
     while (this.hasLayerForName_(name)) {

src/js/controller/piskel/PublicPiskelController.js

@@ -99,6 +99,12 @@
     $.publish(Events.PISKEL_RESET);
   };
 
+  ns.PublicPiskelController.prototype.mergeDownLayerAt = function (index) {
+    this.raiseSaveStateEvent_(this.piskelController.mergeDownLayerAt, [index]);
+    this.piskelController.mergeDownLayerAt(index);
+    $.publish(Events.PISKEL_RESET);
+  };
+
   ns.PublicPiskelController.prototype.moveLayerUp = function () {
     this.raiseSaveStateEvent_(this.piskelController.moveLayerUp, []);
     this.piskelController.moveLayerUp();