Sources may be configured with a projection, tile grids with an extent

An XYZ tile grid is constructed with an extent defining the bounds of the tile grid.

src/ol/source/bingmapssource.js

@@ -89,7 +89,9 @@ ol.source.BingMaps.prototype.handleImageryMetadataResponse =
   var resource = response.resourceSets[0].resources[0];
 
   goog.asserts.assert(resource.imageWidth == resource.imageHeight);
+  var sourceProjection = this.getProjection();
   var tileGrid = new ol.tilegrid.XYZ({
+    extent: ol.tilegrid.extentFromProjection(sourceProjection),
     minZoom: resource.zoomMin,
     maxZoom: resource.zoomMax,
     tileSize: resource.imageWidth
@@ -97,7 +99,6 @@ ol.source.BingMaps.prototype.handleImageryMetadataResponse =
   this.tileGrid = tileGrid;
 
   var culture = this.culture_;
-  var sourceProjection = this.getProjection();
   this.tileUrlFunction = ol.TileUrlFunction.withTileCoordTransform(
       tileGrid.createTileCoordTransform(),
       ol.TileUrlFunction.createFromTileUrlFunctions(

src/ol/source/tilejsonsource.js

@@ -54,10 +54,11 @@ ol.source.TileJSON.prototype.handleTileJSONResponse = function(tileJSON) {
 
   var epsg4326Projection = ol.proj.get('EPSG:4326');
 
+  var sourceProjection = this.getProjection();
   var extent;
   if (goog.isDef(tileJSON.bounds)) {
     var transform = ol.proj.getTransformFromProjections(
-        epsg4326Projection, this.getProjection());
+        epsg4326Projection, sourceProjection);
     extent = ol.extent.applyTransform(tileJSON.bounds, transform);
   }
 
@@ -67,6 +68,7 @@ ol.source.TileJSON.prototype.handleTileJSONResponse = function(tileJSON) {
   var minZoom = tileJSON.minzoom || 0;
   var maxZoom = tileJSON.maxzoom || 22;
   var tileGrid = new ol.tilegrid.XYZ({
+    extent: ol.tilegrid.extentFromProjection(sourceProjection),
     maxZoom: maxZoom,
     minZoom: minZoom
   });

src/ol/source/xyzsource.js

@@ -17,13 +17,12 @@ goog.require('ol.tilegrid.XYZ');
  * @api
  */
 ol.source.XYZ = function(options) {
-
   var projection = goog.isDef(options.projection) ?
       options.projection : 'EPSG:3857';
 
   var tileGrid = new ol.tilegrid.XYZ({
-    maxZoom: options.maxZoom,
-    projection: options.projection
+    extent: ol.tilegrid.extentFromProjection(projection),
+    maxZoom: options.maxZoom
   });
 
   goog.base(this, {

src/ol/tilegrid/xyztilegrid.js

@@ -7,6 +7,7 @@ goog.require('ol.TileRange');
 goog.require('ol.extent');
 goog.require('ol.extent.Corner');
 goog.require('ol.proj');
+goog.require('ol.proj.EPSG3857');
 goog.require('ol.tilecoord');
 goog.require('ol.tilegrid.TileGrid');
 
@@ -23,19 +24,16 @@ goog.require('ol.tilegrid.TileGrid');
  * @api
  */
 ol.tilegrid.XYZ = function(options) {
-  var projection = goog.isDef(options.projection) ?
-      options.projection : 'EPSG:3857';
-  var extent = ol.tilegrid.extentFromProjection(projection);
-
+  // TODO: accept a tileSize option
   var tileSize = ol.DEFAULT_TILE_SIZE;
+  var extent = goog.isDef(options.extent) ?
+      options.extent : ol.proj.EPSG3857.EXTENT;
   var resolutions = ol.tilegrid.resolutionsFromExtent(
       extent, options.maxZoom, tileSize);
 
-  var origin = ol.extent.getCorner(extent, ol.extent.Corner.TOP_LEFT);
-
   goog.base(this, {
     minZoom: options.minZoom,
-    origin: origin,
+    origin: ol.extent.getCorner(extent, ol.extent.Corner.TOP_LEFT),
     resolutions: resolutions,
     tileSize: tileSize
   });