Add specialized ol.tilegrid.XYZ.forEachTileCoordParentTileBounds

src/ol/tile/xyz.js

@@ -40,6 +40,30 @@ ol.tilegrid.XYZ = function(maxZoom, opt_tileSize) {
 goog.inherits(ol.tilegrid.XYZ, ol.TileGrid);
 
 
+/**
+ * @inheritDoc
+ */
+ol.tilegrid.XYZ.prototype.forEachTileCoordParentTileBounds =
+    function(tileCoord, callback, opt_obj) {
+  var x = tileCoord.x;
+  var y = tileCoord.y;
+  var z = tileCoord.z;
+  var tileBounds;
+  while (true) {
+    z -= 1;
+    if (z < 0) {
+      break;
+    }
+    x = Math.floor(x / 2);
+    y = Math.floor(y / 2);
+    tileBounds = new ol.TileBounds(x, y, x, y);
+    if (callback.call(opt_obj, z, tileBounds)) {
+      break;
+    }
+  }
+};
+
+
 
 /**
  * @constructor

src/ol/tile/xyz_test.js

@@ -77,3 +77,53 @@ function testXYZCropY() {
   assertUndefined(tileUrl);
 
 }
+
+
+function testXYZTileGridForEachTileCoordParentTileBounds() {
+
+  var xyzTileGrid = new ol.tilegrid.XYZ(6);
+
+  var tileCoord = new ol.TileCoord(5, 11, 21);
+  var zs = [], tileBoundss = [];
+  xyzTileGrid.forEachTileCoordParentTileBounds(
+      tileCoord,
+      function(z, tileBounds) {
+        zs.push(z);
+        tileBoundss.push(tileBounds);
+        return false;
+      });
+
+  assertEquals(5, zs.length);
+  assertEquals(5, tileBoundss.length);
+
+  assertEquals(4, zs[0]);
+  assertEquals(5, tileBoundss[0].minX);
+  assertEquals(10, tileBoundss[0].minY);
+  assertEquals(5, tileBoundss[0].maxX);
+  assertEquals(10, tileBoundss[0].maxY);
+
+  assertEquals(3, zs[1]);
+  assertEquals(2, tileBoundss[1].minX);
+  assertEquals(5, tileBoundss[1].minY);
+  assertEquals(2, tileBoundss[1].maxX);
+  assertEquals(5, tileBoundss[1].maxY);
+
+  assertEquals(2, zs[2]);
+  assertEquals(1, tileBoundss[2].minX);
+  assertEquals(2, tileBoundss[2].minY);
+  assertEquals(1, tileBoundss[2].maxX);
+  assertEquals(2, tileBoundss[2].maxY);
+
+  assertEquals(1, zs[3]);
+  assertEquals(0, tileBoundss[3].minX);
+  assertEquals(1, tileBoundss[3].minY);
+  assertEquals(0, tileBoundss[3].maxX);
+  assertEquals(1, tileBoundss[3].maxY);
+
+  assertEquals(0, zs[4]);
+  assertEquals(0, tileBoundss[4].minX);
+  assertEquals(0, tileBoundss[4].minY);
+  assertEquals(0, tileBoundss[4].maxX);
+  assertEquals(0, tileBoundss[4].maxY);
+
+}