Merge pull request #79 from ahocevar/projection

Projection handling improvements. r=@twpayne, @elemoine

examples/wms-custom-proj.js

@@ -13,11 +13,12 @@ if (goog.DEBUG) {
   goog.debug.Logger.getLogger('ol').setLevel(goog.debug.Logger.Level.INFO);
 }
 
+var epsg21781 = new ol.Projection('EPSG:21781', ol.ProjectionUnits.METERS,
+    // Validity extent from http://spatialreference.org
+    new ol.Extent(485869.5728, 76443.1884, 837076.5648, 299941.7864));
+ol.Projection.addProjection(epsg21781);
+
 var extent = new ol.Extent(420000, 30000, 900000, 350000);
-
-var epsg21781 = new ol.Projection('EPSG:21781',
-    ol.ProjectionUnits.METERS, extent);
-
 var layers = new ol.Collection([
   new ol.layer.TileLayer({
     source: new ol.source.TiledWMS({
@@ -28,7 +29,8 @@ var layers = new ol.Collection([
           'Pixelmap 1:1000000 / geo.admin.ch</a>')],
       crossOrigin: null,
       params: {'LAYERS': 'ch.swisstopo.pixelkarte-farbe-pk1000.noscale'},
-      projection: epsg21781
+      projection: epsg21781,
+      extent: extent
     })
   }),
   new ol.layer.TileLayer({
@@ -40,7 +42,8 @@ var layers = new ol.Collection([
           'National parks / geo.admin.ch</a>')],
       crossOrigin: null,
       params: {'LAYERS': 'ch.bafu.schutzgebiete-paerke_nationaler_bedeutung'},
-      projection: epsg21781
+      projection: epsg21781,
+      extent: extent
     })
   })
 ]);
@@ -49,6 +52,9 @@ var map = new ol.Map({
   renderer: ol.RendererHint.DOM,
   center: new ol.Coordinate(660000, 190000),
   projection: epsg21781,
+  // By setting userProjection to the same as projection, we do not need
+  // proj4js because we do not need any transforms.
+  userProjection: epsg21781,
   layers: layers,
   target: 'map',
   zoom: 9

src/ol/map.js

@@ -980,7 +980,7 @@ ol.Map.createOptionsInternal = function(mapOptions) {
   values[ol.MapProperty.LAYERS] = goog.isDef(mapOptions.layers) ?
       mapOptions.layers : new ol.Collection();
 
-  values[ol.MapProperty.PROJECTION] = ol.Map.createProjection_(
+  values[ol.MapProperty.PROJECTION] = ol.Projection.createProjection(
       mapOptions.projection, 'EPSG:3857');
 
   if (goog.isDef(mapOptions.resolution)) {
@@ -990,7 +990,7 @@ ol.Map.createOptionsInternal = function(mapOptions) {
         ol.Projection.EPSG_3857_HALF_SIZE / (128 << mapOptions.zoom);
   }
 
-  values[ol.MapProperty.USER_PROJECTION] = ol.Map.createProjection_(
+  values[ol.MapProperty.USER_PROJECTION] = ol.Projection.createProjection(
       mapOptions.userProjection, 'EPSG:4326');
 
   /**
@@ -1183,21 +1183,3 @@ ol.Map.createInteractions_ = function(mapOptions) {
   return interactions;
 
 };
-
-
-/**
- * @private
- * @param {ol.Projection|string|undefined} projection Projection.
- * @param {string} defaultCode Default code.
- * @return {ol.Projection} Projection.
- */
-ol.Map.createProjection_ = function(projection, defaultCode) {
-  if (!goog.isDefAndNotNull(projection)) {
-    return ol.Projection.getFromCode(defaultCode);
-  } else if (goog.isString(projection)) {
-    return ol.Projection.getFromCode(projection);
-  } else {
-    goog.asserts.assert(projection instanceof ol.Projection);
-    return projection;
-  }
-};

src/ol/projection.js

@@ -137,8 +137,10 @@ ol.Projection.addEquivalentProjections_ = function(projections) {
   ol.Projection.addProjections(projections);
   goog.array.forEach(projections, function(source) {
     goog.array.forEach(projections, function(destination) {
-      ol.Projection.addTransform(
-          source, destination, ol.Projection.cloneTransform);
+      if (source !== destination) {
+        ol.Projection.addTransform(
+            source, destination, ol.Projection.cloneTransform);
+      }
     });
   });
 };
@@ -181,6 +183,8 @@ ol.Projection.addProjection = function(projection) {
   var code = projection.getCode();
   goog.asserts.assert(!goog.object.containsKey(projections, code));
   projections[code] = projection;
+  ol.Projection.addTransform(
+      projection, projection, ol.Projection.cloneTransform);
 };
 
 
@@ -194,6 +198,23 @@ ol.Projection.addProjections = function(projections) {
 };
 
 
+/**
+ * @param {ol.Projection|string|undefined} projection Projection.
+ * @param {string} defaultCode Default code.
+ * @return {ol.Projection} Projection.
+ */
+ol.Projection.createProjection = function(projection, defaultCode) {
+  if (!goog.isDefAndNotNull(projection)) {
+    return ol.Projection.getFromCode(defaultCode);
+  } else if (goog.isString(projection)) {
+    return ol.Projection.getFromCode(projection);
+  } else {
+    goog.asserts.assert(projection instanceof ol.Projection);
+    return projection;
+  }
+};
+
+
 /**
  * @param {ol.Projection} source Source.
  * @param {ol.Projection} destination Destination.

src/ol/source/tiledwmssource.js

@@ -2,6 +2,7 @@
 
 goog.provide('ol.source.TiledWMS');
 
+
 goog.require('goog.asserts');
 goog.require('goog.object');
 goog.require('ol.Attribution');
@@ -19,8 +20,8 @@ goog.require('ol.tilegrid.TileGrid');
  * @param {ol.source.TiledWMSOptions} tiledWMSOptions options.
  */
 ol.source.TiledWMS = function(tiledWMSOptions) {
-  var projection = goog.isDef(tiledWMSOptions.projection) ?
-      tiledWMSOptions.projection : ol.Projection.getFromCode('EPSG:3857');
+  var projection = ol.Projection.createProjection(
+      tiledWMSOptions.projection, 'EPSG:3857');
   var projectionExtent = projection.getExtent();
 
   var extent = goog.isDef(tiledWMSOptions.extent) ?
@@ -39,7 +40,7 @@ ol.source.TiledWMS = function(tiledWMSOptions) {
         tiledWMSOptions.maxZoom : 18;
     var resolutions = new Array(maxZoom + 1);
     for (var z = 0, zz = resolutions.length; z < zz; ++z) {
-      resolutions[z] = size / (256 << z);
+      resolutions[z] = ol.Projection.EPSG_3857_HALF_SIZE / (128 << z);
     }
     tileGrid = new ol.tilegrid.TileGrid({
       origin: projectionExtent.getTopLeft(),
@@ -85,15 +86,17 @@ ol.source.TiledWMS = function(tiledWMSOptions) {
       return null;
     }
     var x = tileCoord.x;
+    var tileExtent = tileGrid.getTileCoordExtent(tileCoord);
     // 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 &&
         extent.maxX === projectionExtent.maxX) {
-      var n = 1 << tileCoord.z;
-      x = goog.math.modulo(x, n);
+      var numCols = Math.ceil(
+          (extent.maxX - extent.minX) / (tileExtent.maxX - tileExtent.minX));
+      x = goog.math.modulo(x, numCols);
+      tileExtent = tileGrid.getTileCoordExtent(
+          new ol.TileCoord(tileCoord.z, x, tileCoord.y));
     }
-    var tileExtent = tileGrid.getTileCoordExtent(
-        new ol.TileCoord(tileCoord.z, x, tileCoord.y));
     // FIXME We shouldn't need a typecast here.
     if (!tileExtent.intersects(/** @type {ol.Extent} */ (extent))) {
       return null;