Support tile sources without configured projection

This change adds a lot of flexibility to working with tile
layers: Sources where the server projection or tile grid do not
matter can now be constructed without specifying a projection or
tile grid.

The tileUrlFunction/imageUrlFunction now also creates updated
URLs when the params of the layer change, so things like
mergeNewParams in ol2 will be possible.

A nice side effect of this whole change is that there is no more
duplicated code between tiled and single image WMS layers.

While I was at it, I also fixed a WMS 1.1.1 axis order issue
and incorrect STYLES params (STYLES=& instead of STYLES&).

src/ol/source/tiledwmssource.js

@@ -4,12 +4,9 @@ goog.provide('ol.source.TiledWMS');
 
 
 goog.require('goog.array');
-goog.require('goog.object');
-goog.require('goog.uri.utils');
 goog.require('ol.Extent');
 goog.require('ol.TileCoord');
 goog.require('ol.TileUrlFunction');
-goog.require('ol.projection');
 goog.require('ol.source.ImageTileSource');
 
 
@@ -20,64 +17,40 @@ goog.require('ol.source.ImageTileSource');
  * @param {ol.source.TiledWMSOptions} tiledWMSOptions options.
  */
 ol.source.TiledWMS = function(tiledWMSOptions) {
-  var projection = ol.projection.createProjection(
-      tiledWMSOptions.projection, 'EPSG:3857');
-  var projectionExtent = projection.getExtent();
-
-  var extent = goog.isDef(tiledWMSOptions.extent) ?
-      tiledWMSOptions.extent : projectionExtent;
-
-  var version = goog.isDef(tiledWMSOptions.version) ?
-      tiledWMSOptions.version : '1.3';
-
   var tileGrid;
   if (goog.isDef(tiledWMSOptions.tileGrid)) {
     tileGrid = tiledWMSOptions.tileGrid;
-  } else {
-    tileGrid = ol.tilegrid.createForProjection(projection,
-        tiledWMSOptions.maxZoom);
   }
+  var version = tiledWMSOptions.version;
 
-  var baseParams = {
-    'SERVICE': 'WMS',
-    'VERSION': version,
-    'REQUEST': 'GetMap',
-    'STYLES': '',
-    'FORMAT': 'image/png',
-    'TRANSPARENT': true
-  };
-  baseParams[version >= '1.3' ? 'CRS' : 'SRS'] = projection.getCode();
-  goog.object.extend(baseParams, tiledWMSOptions.params);
-
-  var axisOrientation = projection.getAxisOrientation();
   var tileUrlFunction;
   if (tiledWMSOptions.urls) {
     var tileUrlFunctions = goog.array.map(
         tiledWMSOptions.urls, function(url) {
-          url = goog.uri.utils.appendParamsFromMap(url, baseParams);
-          return ol.TileUrlFunction.createBboxParam(
-              url, tileGrid, axisOrientation);
+          return ol.TileUrlFunction.createWMSParams(
+              url, tiledWMSOptions.params, version);
         });
     tileUrlFunction = ol.TileUrlFunction.createFromTileUrlFunctions(
         tileUrlFunctions);
   } else if (tiledWMSOptions.url) {
-    var url = goog.uri.utils.appendParamsFromMap(
-        tiledWMSOptions.url, baseParams);
-    tileUrlFunction =
-        ol.TileUrlFunction.createBboxParam(url, tileGrid, axisOrientation);
+    tileUrlFunction = ol.TileUrlFunction.createWMSParams(
+        tiledWMSOptions.url, tiledWMSOptions.params, version);
   } else {
     tileUrlFunction = ol.TileUrlFunction.nullTileUrlFunction;
   }
 
-  var tileCoordTransform = function(tileCoord) {
+  var extent = tiledWMSOptions.extent;
+
+  var tileCoordTransform = function(tileCoord, tileGrid, projection) {
     if (tileGrid.getResolutions().length <= tileCoord.z) {
       return null;
     }
     var x = tileCoord.x;
     var tileExtent = tileGrid.getTileCoordExtent(tileCoord);
+    var projectionExtent = projection.getExtent();
     // FIXME do we want a wrapDateLine param? The code below will break maps
     // with projections that do not span the whole world width.
-    if (extent.minX === projectionExtent.minX &&
+    if (extent && extent.minX === projectionExtent.minX &&
         extent.maxX === projectionExtent.maxX) {
       var numCols = Math.ceil(
           (extent.maxX - extent.minX) / (tileExtent.maxX - tileExtent.minX));
@@ -96,8 +69,8 @@ ol.source.TiledWMS = function(tiledWMSOptions) {
     attributions: tiledWMSOptions.attributions,
     crossOrigin: tiledWMSOptions.crossOrigin,
     extent: extent,
-    tileGrid: tileGrid,
-    projection: projection,
+    tileGrid: tiledWMSOptions.tileGrid,
+    projection: tiledWMSOptions.projection,
     tileUrlFunction: ol.TileUrlFunction.withTileCoordTransform(
         tileCoordTransform, tileUrlFunction)
   });