For gridded layers where the tile lattice on the server doesn't align with the maxExtent on the client, set the layer tileExtent property. r=ahocevar (closes #3002)

git-svn-id: http://svn.openlayers.org/trunk/openlayers@11002 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Layer/Grid.js

@@ -25,6 +25,12 @@ OpenLayers.Layer.Grid = OpenLayers.Class(OpenLayers.Layer.HTTPRequest, {
      */
     tileSize: null,
     
+    /**
+     * APIProperty: tileExtent
+     * {<OpenLayers.Bounds>}
+     */
+    tileExtent: null,
+    
     /** APIProperty: tileOptions
      *  {Object} optional configuration options for <OpenLayers.Tile> instances
      *  created by this Layer, if supported by the tile class.
@@ -446,7 +452,7 @@ OpenLayers.Layer.Grid = OpenLayers.Class(OpenLayers.Layer.HTTPRequest, {
      * {OpenLayers.Bounds}
      */
     getMaxExtent: function() {
-        return this.maxExtent;
+        return this.tileExtent || this.maxExtent;
     },
     
     /**

tests/Layer/WMS.html

@@ -154,7 +154,6 @@
         map.destroy();
     }
 
-
     function test_Layer_WMS_clone (t) {
         t.plan(4);
 
@@ -381,6 +380,39 @@
 
     }
 
+    function test_tileExtent(t) {
+        t.plan(4);
+        
+        var dummy = new OpenLayers.Layer(null, {isBaseLayer: true});
+        var unconstrained = new OpenLayers.Layer.WMS(
+            null, "http://example.com/wms", 
+            {layers: "unconstrained"}, 
+            {isBaseLayer: false, buffer: 0}
+        );
+        var constrained = new OpenLayers.Layer.WMS(
+            null, "http://example.com/wms-c", 
+            {layers: "constrained"}, 
+            {buffer: 0, isBaseLayer: false, tileExtent: new OpenLayers.Bounds(-180, -90, 180, 90)}
+        );
+        var map = new OpenLayers.Map({
+            div: "map",
+            maxExtent: new OpenLayers.Bounds(-185, -95, 185, 95),
+            layers: [dummy, unconstrained, constrained],
+            center: new OpenLayers.LonLat(0, 0),
+            zoom: 1
+        });
+        
+        t.eq(unconstrained.grid[1][0].bounds.bottom, -95, "unconstrained bottom correct");
+        t.eq(unconstrained.grid[1][0].bounds.left, -185, "unconstrained left correct");
+        t.eq(constrained.grid[1][0].bounds.bottom, -90, "constrained bottom correct");
+        t.eq(constrained.grid[1][0].bounds.left, -180, "constrained left correct");
+        
+        map.destroy();
+        
+    }
+
+
+
     // DEPRECATED -- REMOVE IN 3.0
     function test_Layer_Untiled_WMS(t) {
         t.plan(1);