Add frameState to postcompose event and minimise calls to getTransform

src/ol/render/renderevent.js

@@ -20,11 +20,12 @@ ol.render.RenderEventType = {
  * @param {ol.render.RenderEventType} type Type.
  * @param {Object=} opt_target Target.
  * @param {ol.render.IRender=} opt_render Render.
+ * @param {ol.FrameState=} opt_frameState Frame state.
  * @param {?CanvasRenderingContext2D=} opt_context Context.
  * @param {?WebGLRenderingContext=} opt_gl GL.
  */
-ol.render.RenderEvent =
-    function(type, opt_target, opt_render, opt_context, opt_gl) {
+ol.render.RenderEvent = function(
+    type, opt_target, opt_render, opt_frameState, opt_context, opt_gl) {
 
   goog.base(this, type, opt_target);
 
@@ -34,6 +35,12 @@ ol.render.RenderEvent =
    */
   this.render_ = opt_render;
 
+  /**
+   * @type {ol.FrameState|undefined}
+   * @private
+   */
+  this.frameState_ = opt_frameState;
+
   /**
    * @type {CanvasRenderingContext2D|null|undefined}
    * @private
@@ -58,6 +65,14 @@ ol.render.RenderEvent.prototype.getContext = function() {
 };
 
 
+/**
+ * @return {ol.FrameState|undefined} Frame state.
+ */
+ol.render.RenderEvent.prototype.getFrameState = function() {
+  return this.frameState_;
+};
+
+
 /**
  * @return {WebGLRenderingContext|null|undefined} GL.
  */