From e30109913e8be94517b1a0a2e5890ddab97c626f Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Tue, 9 Apr 2013 15:53:31 +0200
Subject: [PATCH] Enable ol.TileRange re-use

---
 src/ol/tilegrid/tilegrid.js    | 28 ++++++++++++++++++----------
 src/ol/tilegrid/xyztilegrid.js | 13 ++++++++-----
 2 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/src/ol/tilegrid/tilegrid.js b/src/ol/tilegrid/tilegrid.js
index 91863a9540..d80e21878f 100644
--- a/src/ol/tilegrid/tilegrid.js
+++ b/src/ol/tilegrid/tilegrid.js
@@ -96,16 +96,17 @@ ol.tilegrid.TileGrid = function(options) {
  * @param {ol.TileCoord} tileCoord Tile coordinate.
  * @param {function(this: T, number, ol.TileRange): boolean} callback Callback.
  * @param {T=} opt_obj Object.
+ * @param {ol.TileRange=} opt_tileRange Temporary ol.TileRange object.
  * @return {boolean} Callback succeeded.
  * @template T
  */
 ol.tilegrid.TileGrid.prototype.forEachTileCoordParentTileRange =
-    function(tileCoord, callback, opt_obj) {
+    function(tileCoord, callback, opt_obj, opt_tileRange) {
   var tileCoordExtent = this.getTileCoordExtent(tileCoord);
   var z = tileCoord.z - 1;
   while (z >= 0) {
-    if (callback.call(
-        opt_obj, z, this.getTileRangeForExtentAndZ(tileCoordExtent, z))) {
+    if (callback.call(opt_obj, z,
+        this.getTileRangeForExtentAndZ(tileCoordExtent, z, opt_tileRange))) {
       return true;
     }
     --z;
@@ -168,13 +169,15 @@ ol.tilegrid.TileGrid.prototype.getResolutions = function() {
 
 /**
  * @param {ol.TileCoord} tileCoord Tile coordinate.
+ * @param {ol.TileRange=} opt_tileRange Temporary ol.TileRange object.
  * @return {ol.TileRange} Tile range.
  */
 ol.tilegrid.TileGrid.prototype.getTileCoordChildTileRange =
-    function(tileCoord) {
+    function(tileCoord, opt_tileRange) {
   if (tileCoord.z < this.resolutions_.length) {
     var tileCoordExtent = this.getTileCoordExtent(tileCoord);
-    return this.getTileRangeForExtentAndZ(tileCoordExtent, tileCoord.z + 1);
+    return this.getTileRangeForExtentAndZ(
+        tileCoordExtent, tileCoord.z + 1, opt_tileRange);
   } else {
     return null;
   }
@@ -201,28 +204,33 @@ ol.tilegrid.TileGrid.prototype.getTileRangeExtent = function(z, tileRange) {
 /**
  * @param {ol.Extent} extent Extent.
  * @param {number} resolution Resolution.
+ * @param {ol.TileRange=} opt_tileRange Temporary tile range object.
  * @return {ol.TileRange} Tile range.
  */
-ol.tilegrid.TileGrid.prototype.getTileRangeForExtentAndResolution = function(
-    extent, resolution) {
+ol.tilegrid.TileGrid.prototype.getTileRangeForExtentAndResolution =
+    function(extent, resolution, opt_tileRange) {
   var tileCoord = this.getTileCoordForXYAndResolution_(
       extent.minX, extent.minY, resolution, false);
   var minX = tileCoord.x;
   var minY = tileCoord.y;
   tileCoord = this.getTileCoordForXYAndResolution_(
       extent.maxX, extent.maxY, resolution, true, tileCoord);
-  return new ol.TileRange(minX, minY, tileCoord.x, tileCoord.y);
+  return ol.TileRange.createOrUpdate(
+      minX, minY, tileCoord.x, tileCoord.y, opt_tileRange);
 };
 
 
 /**
  * @param {ol.Extent} extent Extent.
  * @param {number} z Z.
+ * @param {ol.TileRange=} opt_tileRange Temporary tile range object.
  * @return {ol.TileRange} Tile range.
  */
-ol.tilegrid.TileGrid.prototype.getTileRangeForExtentAndZ = function(extent, z) {
+ol.tilegrid.TileGrid.prototype.getTileRangeForExtentAndZ =
+    function(extent, z, opt_tileRange) {
   var resolution = this.getResolution(z);
-  return this.getTileRangeForExtentAndResolution(extent, resolution);
+  return this.getTileRangeForExtentAndResolution(
+      extent, resolution, opt_tileRange);
 };
 
 
diff --git a/src/ol/tilegrid/xyztilegrid.js b/src/ol/tilegrid/xyztilegrid.js
index 49829503b2..036c414640 100644
--- a/src/ol/tilegrid/xyztilegrid.js
+++ b/src/ol/tilegrid/xyztilegrid.js
@@ -42,11 +42,13 @@ goog.inherits(ol.tilegrid.XYZ, ol.tilegrid.TileGrid);
 /**
  * @inheritDoc
  */
-ol.tilegrid.XYZ.prototype.getTileCoordChildTileRange = function(tileCoord) {
+ol.tilegrid.XYZ.prototype.getTileCoordChildTileRange =
+    function(tileCoord, opt_tileRange) {
   if (tileCoord.z < this.maxZoom_) {
-    return new ol.TileRange(
+    return ol.TileRange.createOrUpdate(
         tileCoord.x << 1, tileCoord.y << 1,
-        tileCoord.x + 1 << 1, tileCoord.y + 1 << 1);
+        tileCoord.x + 1 << 1, tileCoord.y + 1 << 1,
+        opt_tileRange);
   } else {
     return null;
   }
@@ -57,8 +59,9 @@ ol.tilegrid.XYZ.prototype.getTileCoordChildTileRange = function(tileCoord) {
  * @inheritDoc
  */
 ol.tilegrid.XYZ.prototype.forEachTileCoordParentTileRange =
-    function(tileCoord, callback, opt_obj) {
-  var tileRange = new ol.TileRange(0, 0, tileCoord.x, tileCoord.y);
+    function(tileCoord, callback, opt_obj, opt_tileRange) {
+  var tileRange = ol.TileRange.createOrUpdate(
+      0, 0, tileCoord.x, tileCoord.y, opt_tileRange);
   var z;
   for (z = tileCoord.z - 1; z >= 0; --z) {
     tileRange.minX = tileRange.maxX >>= 1;