Give tile grids a width

src/ol/tilegrid/tilegrid.js

@@ -92,6 +92,16 @@ ol.tilegrid.TileGrid = function(options) {
       (!goog.isDef(this.tileSize_) && !goog.isNull(this.tileSizes_)) ||
       (goog.isDef(this.tileSize_) && goog.isNull(this.tileSizes_)));
 
+  /**
+   * @private
+   * @type {Array.<number>}
+   */
+  this.widths_ = null;
+  if (goog.isDef(options.widths)) {
+    this.widths_ = options.widths;
+    goog.asserts.assert(this.widths_.length == this.resolutions_.length);
+  }
+
 };
 
 
@@ -373,6 +383,25 @@ ol.tilegrid.TileGrid.prototype.getTileCoordResolution = function(tileCoord) {
 };
 
 
+/**
+ * @param {number} z Zoom level.
+ * @param {ol.proj.Projection} projection Projection.
+ * @param {ol.TileRange=} opt_tileRange Tile range.
+ * @return {ol.TileRange} Tile range.
+ */
+ol.tilegrid.TileGrid.prototype.getTileRange =
+    function(z, projection, opt_tileRange) {
+  var projectionExtentTileRange = this.getTileRangeForExtentAndZ(
+      ol.tilegrid.extentFromProjection(projection), z);
+  var width = this.getWidth(z);
+  if (!goog.isDef(width)) {
+    width = projectionExtentTileRange.getWidth();
+  }
+  return ol.TileRange.createOrUpdate(
+      0, width - 1, 0, projectionExtentTileRange.getHeight(), opt_tileRange);
+};
+
+
 /**
  * @param {number} z Z.
  * @return {number} Tile size.
@@ -389,6 +418,19 @@ ol.tilegrid.TileGrid.prototype.getTileSize = function(z) {
 };
 
 
+/**
+ * @param {number} z Zoom level.
+ * @return {number|undefined} Width for the specified zoom level or `undefined`
+ *     if unknown.
+ */
+ol.tilegrid.TileGrid.prototype.getWidth = function(z) {
+  if (!goog.isNull(this.widths_)) {
+    goog.asserts.assert(this.minZoom <= z && z <= this.maxZoom);
+    return this.widths_[z];
+  }
+};
+
+
 /**
  * @param {number} resolution Resolution.
  * @return {number} Z.
@@ -399,6 +441,26 @@ ol.tilegrid.TileGrid.prototype.getZForResolution = function(resolution) {
 };
 
 
+/**
+ * @param {number} z Zoom level.
+ * @param {ol.proj.Projection} projection Projection.
+ * @return {boolean} Whether the tile grid is defined for the whole globe when
+ *     used with the provided `projection` at zoom level `z`.
+ */
+ol.tilegrid.TileGrid.prototype.isGlobal = function(z, projection) {
+  var width = this.getWidth(z);
+  if (goog.isDef(width)) {
+    var projTileGrid = ol.tilegrid.getForProjection(projection);
+    var projExtent = projection.getExtent();
+    return this.getTileSize(z) * width ==
+        projTileGrid.getTileSize(z) *
+        projTileGrid.getTileRangeForExtentAndZ(projExtent, z).getWidth();
+  } else {
+    return projection.isGlobal();
+  }
+};
+
+
 /**
  * @param {ol.proj.Projection} projection Projection.
  * @return {ol.tilegrid.TileGrid} Default tile grid for the passed projection.
@@ -433,10 +495,17 @@ ol.tilegrid.createForExtent =
   var resolutions = ol.tilegrid.resolutionsFromExtent(
       extent, opt_maxZoom, tileSize);
 
+  var widths = new Array(resolutions.length);
+  var extentWidth = ol.extent.getWidth(extent);
+  for (var z = resolutions.length - 1; z >= 0; --z) {
+    widths[z] = extentWidth / tileSize / resolutions[z];
+  }
+
   return new ol.tilegrid.TileGrid({
     origin: ol.extent.getCorner(extent, corner),
     resolutions: resolutions,
-    tileSize: tileSize
+    tileSize: tileSize,
+    widths: widths
   });
 };
 

src/ol/tilegrid/wmtstilegrid.js

@@ -34,7 +34,8 @@ ol.tilegrid.WMTS = function(options) {
     origins: options.origins,
     resolutions: options.resolutions,
     tileSize: options.tileSize,
-    tileSizes: options.tileSizes
+    tileSizes: options.tileSizes,
+    widths: options.widths
   });
 
 };
@@ -77,6 +78,8 @@ ol.tilegrid.WMTS.createFromCapabilitiesMatrixSet =
   var origins = [];
   /** @type {!Array.<number>} */
   var tileSizes = [];
+  /** @type {!Array.<number>} */
+  var widths = [];
 
   var supportedCRSPropName = 'SupportedCRS';
   var matrixIdsPropName = 'TileMatrix';
@@ -112,12 +115,14 @@ ol.tilegrid.WMTS.createFromCapabilitiesMatrixSet =
         var tileHeight = elt[tileHeightPropName];
         goog.asserts.assert(tileWidth == tileHeight);
         tileSizes.push(tileWidth);
+        widths.push(elt['MatrixWidth']);
       });
 
   return new ol.tilegrid.WMTS({
     origins: origins,
     resolutions: resolutions,
     matrixIds: matrixIds,
-    tileSizes: tileSizes
+    tileSizes: tileSizes,
+    widths: widths
   });
 };