Merge pull request #121 from twpayne/attribution-control-refactoring

Attribution control refactoring

src/ol/renderer/dom/domtilelayerrenderer.js

@@ -236,6 +236,8 @@ ol.renderer.dom.TileLayer.prototype.renderFrame =
     frameState.animate = true;
   }
 
+  this.updateTileUsage(frameState.tileUsage, tileSource, z, tileRange);
+
 };
 
 

src/ol/renderer/layerrenderer.js

@@ -3,6 +3,7 @@ goog.provide('ol.renderer.Layer');
 goog.require('goog.events');
 goog.require('goog.events.EventType');
 goog.require('ol.Object');
+goog.require('ol.TileRange');
 goog.require('ol.layer.Layer');
 goog.require('ol.layer.LayerProperty');
 
@@ -125,3 +126,28 @@ ol.renderer.Layer.prototype.handleLayerSaturationChange = goog.nullFunction;
  * @protected
  */
 ol.renderer.Layer.prototype.handleLayerVisibleChange = goog.nullFunction;
+
+
+/**
+ * @protected
+ * @param {Object.<string, Object.<string, ol.TileRange>>} tileUsage Tile usage.
+ * @param {ol.source.Source} source Source.
+ * @param {number} z Z.
+ * @param {ol.TileRange} tileRange Tile range.
+ */
+ol.renderer.Layer.prototype.updateTileUsage =
+    function(tileUsage, source, z, tileRange) {
+  // FIXME should we use tilesToDrawByZ instead?
+  var sourceKey = goog.getUid(source).toString();
+  var zKey = z.toString();
+  if (sourceKey in tileUsage) {
+    if (z in tileUsage[sourceKey]) {
+      tileUsage[sourceKey][zKey].extend(tileRange);
+    } else {
+      tileUsage[sourceKey][zKey] = tileRange;
+    }
+  } else {
+    tileUsage[sourceKey] = {};
+    tileUsage[sourceKey][zKey] = tileRange;
+  }
+};

src/ol/renderer/webgl/webgltilelayerrenderer.js

@@ -277,7 +277,6 @@ ol.renderer.webgl.TileLayer.prototype.renderFrame =
       frameState.extent, tileResolution);
 
   var framebufferExtent;
-
   if (!goog.isNull(this.renderedTileRange_) &&
       this.renderedTileRange_.equals(tileRange)) {
     framebufferExtent = this.renderedFramebufferExtent_;
@@ -460,6 +459,8 @@ ol.renderer.webgl.TileLayer.prototype.renderFrame =
 
   }
 
+  this.updateTileUsage(frameState.tileUsage, tileSource, z, tileRange);
+
   goog.vec.Mat4.makeIdentity(this.matrix_);
   goog.vec.Mat4.translate(this.matrix_,
       (view2DState.center.x - framebufferExtent.minX) /