removed auto-script loader from VirtualEarth.js, beginning adding accessor and translation functions so that it can be used as a base layer. still not complete.

git-svn-id: http://svn.openlayers.org/trunk/openlayers@947 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Layer/VirtualEarth.js

@@ -1,12 +1,55 @@
 /* Copyright (c) 2006 MetaCarta, Inc., published under the BSD license.
  * See http://svn.openlayers.org/trunk/openlayers/license.txt for the full
  * text of the license. */
+
 // @require: OpenLayers/Layer.js
-
+
-// load VE map control script
+if (typeof VEMap != "undefined") {
-document.write("<script src='http://dev.virtualearth.net/mapcontrol/v3/mapcontrol.js'></script>");
+    
-
+    /** Hack-on function because VE does not give it to us
-
+     * 
+     * @param {VELatLong} veLatLng 
+     *
+     * @returns A Pixel specifying veLatLong translated into "Container" coords
+     * @type Pixel
+     */
+    VEMap.prototype.fromLatLngToContainerPixel = function(veLatLong) {
+    
+        // first we translate into "DivPixel"
+        var pixel = this.LatLongToPixel(veLatLong);
+    
+        // locate the upper-left tile
+        var tile = this.mapelement.firstChild.childNodes[2];
+    
+        // adjust by the offset of tile
+        pixel.x += tile.offsetLeft;
+        pixel.y += tile.offsetTop;
+    
+        return pixel;
+    };
+
+    /** Hack-on function because VE does not give it to us
+     * 
+     * @param {Pixel} pixel
+     *
+     * @returns A VELatLong specifying "Container" pixel translated to lonlat
+     * @type VELatLong
+     */
+    VEMap.prototype.fromContainerPixelToLatLng = function(pixel) {
+    
+        // locate the upper-left tile
+        var tile = this.mapelement.firstChild.childNodes[2];
+    
+        // adjust by the offset of tile
+        pixel.x -= tile.offsetLeft;
+        pixel.y -= tile.offsetTop;
+
+        // first we translate into "DivPixel"
+        return this.PixelToLatLong(pixel);
+    };
+
+}
+
 /**
  * @class 
  */
@@ -74,20 +117,74 @@ OpenLayers.Layer.VirtualEarth.prototype =
         veDiv.style.height = sz.h;
         this.div.appendChild(veDiv);
 
-        // create VEMap, hide nav controls
+        try {
-        this.vemap = new VEMap(this.name);
+
-        this.vemap.LoadMap();
+            // create VEMap, hide nav controls
-        this.vemap.HideDashboard();
+            this.vemap = new VEMap(this.name);
-
+            this.vemap.LoadMap();
-        // catch pans and zooms from VE Map
+            this.vemap.HideDashboard();
-        this.vemap.AttachEvent("onendcontinuouspan", 
+    
-                               this.catchPanZoom.bindAsEventListener(this)); 
+            // catch pans and zooms from VE Map
-        this.vemap.AttachEvent("onendzoom", 
+            this.vemap.AttachEvent("onendcontinuouspan", 
-                               this.catchPanZoom.bindAsEventListener(this)); 
+                                   this.catchPanZoom.bindAsEventListener(this)); 
-        
+            this.vemap.AttachEvent("onendzoom", 
-
+                                   this.catchPanZoom.bindAsEventListener(this)); 
+        } catch (e) {
+            this.loadWarningMessage();
+        }
+ 
     },
 
+    /** If we can't load the vemap, then display an error message to the 
+     *   user and tell them where to go for help.
+     * 
+     * @private
+     * 
+     */
+    loadWarningMessage:function() {
+
+        this.div.style.backgroundColor = "red";
+
+        var html = "";
+        html += "The VE Layer was unable to load correctly.<br>";
+        html += "<br>";
+        html += "To get rid of this message, click on the VE Layer's "
+        html += "tab in the layer switcher in the upper-right corner.<br>";
+        html += "<br>";
+        html += "Most likely, this is because the VE library";
+        html += " script was either not correctly included.<br>";
+        html += "<br>";
+        html += "Developers: For help getting this working correctly, ";
+        html += "<a href='http://trac.openlayers.org/wiki/VE' "
+        html +=  "target='_blank'>";
+        html +=     "click here";
+        html += "</a>";
+        
+        var viewSize = this.map.getSize();
+        
+        msgW = Math.min(viewSize.w, 300);
+        msgH = Math.min(viewSize.h, 200);
+        var size = new OpenLayers.Size(msgW, msgH);
+
+        var centerPx = new OpenLayers.Pixel(viewSize.w/2, viewSize.h/2);
+
+        var topLeft = centerPx.add(-size.w/2, -size.h/2);            
+
+        var div = OpenLayers.Util.createDiv("veWarning", 
+                                            topLeft, 
+                                            size,
+                                            null,
+                                            null,
+                                            null,
+                                            "auto");
+
+        div.style.padding = "7px";
+        div.style.backgroundColor = "yellow";
+
+        div.innerHTML = html;
+        this.div.appendChild(div);
+    },
+    
     /**
      * @param {event} e
      */
@@ -95,13 +192,256 @@ OpenLayers.Layer.VirtualEarth.prototype =
         var veCenter = this.vemap.GetCenter();
         var veZoom = this.vemap.GetZoomLevel();
         
-        var olCenter = new OpenLayers.LonLat(veCenter.Longitude,
+        var olCenter = this.getOLLonLatFromVELatLong(veCenter);
-                                             veCenter.Latitude);
+        var olZoom = this.getOLZoomFromVEZoom(veZoom);
-                                             
+        
-        this.map.setCenter(olCenter, veZoom - 1);
+        this.map.setCenter(olCenter, olZoom);
-        
     },
-
+
+
+
+  /********************************************************/
+  /*                                                      */
+  /*                 Baselayer Functions                  */
+  /*                                                      */
+  /********************************************************/
+
+    /**
+     * @param {OpenLayers.Pixel} viewPortPx
+     *
+     * @returns An OpenLayers.LonLat which is the passed-in view port
+     *          OpenLayers.Pixel, translated into lon/lat by VE
+     *          If vemap is not loaded, returns null.
+     * @type OpenLayers.LonLat
+     */
+    getLonLatFromViewPortPx: function (viewPortPx) {
+        var lonlat = null;
+        if (this.vemap != null) {
+            var pixel = this.getPixelFromOLPixel(viewPortPx);
+
+            // note we use special hacked function here
+            var veLatLong = this.vemap.fromContainerPixelToLatLng(pixel)
+
+            lonlat = this.getOLLonLatFromVELatLong(veLatLong);
+        }
+        return lonlat;
+    },
+
+ 
+    /**
+     * @param {OpenLayers.LonLat} lonlat
+     *
+     * @returns An OpenLayers.Pixel which is the passed-in OpenLayers.LonLat, 
+     *          translated into view port pixels BY VE
+     *          If vemap is not loaded, returns null.
+     * @type OpenLayers.Pixel
+     */
+    getViewPortPxFromLonLat: function (lonlat) {
+        var viewPortPx = null;
+        if (this.vemap != null) {
+            var veLatLong = this.getVELatLongFromOLLonLat(lonlat);
+        
+            // note we use special hacked function here
+            var pixel = this.vemap.fromLatLngToContainerPixel(veLatLong);
+        
+            viewPortPx = this.getOLPixelFromPixel(pixel);
+        }
+        return viewPortPx;
+    },
+
+
+    /**
+     * @param {OpenLayers.Bounds} bounds
+     *
+     * @returns Corresponding zoom level for a specified Bounds. 
+     *          If vemap is not loaded, returns null.
+     * @type int
+     */
+    getZoomForExtent: function (bounds) {
+        var zoom = null;
+        if (this.vemap != null) {
+            var gBounds = this.getVELatLongBoundsFromOLBounds(bounds);
+            var gZoom = this.vemap.getBoundsZoomLevel(gBounds);
+            zoom = this.getOLZoomFromGZoom(gZoom);
+        }
+        return zoom;
+    },
+
+    /**
+     * @returns A Bounds object which represents the lon/lat bounds of the 
+     *          current viewPort.
+     *          If vemap is not loaded, returns null
+     * @type OpenLayers.Bounds
+     */
+    getExtent: function () {
+        var extent = null;
+        if (this.vemap != null) {
+            if (this.vemap.getCenter() == null) {
+                this.moveTo();
+            }
+            var veLatLongBounds = this.vemap.getBounds();
+            extent = this.getOLBoundsFromVELatLongBounds(veLatLongBounds);
+        }
+        return extent;
+    },
+ 
+ 
+  /********************************************************/
+  /*                                                      */
+  /*             Translation Functions                    */
+  /*                                                      */
+  /*    The following functions translate GMaps and OL    */ 
+  /*     formats for Pixel, LonLat, Bounds, and Zoom      */
+  /*                                                      */
+  /********************************************************/
+
+  //
+  // TRANSLATION: GZoom <-> OpenLayers Zoom
+  //
+  
+    /**
+     * @param {int} veZoom
+     * 
+     * @returns An OpenLayers Zoom level, translated from the passed in veZoom
+     *          Returns null if null value is passed in
+     * @type int
+     */
+    getOLZoomFromVEZoom: function(veZoom) {
+        var zoom = null;
+        if (veZoom != null) {
+            zoom = veZoom - 1;
+        }
+        return zoom;
+    },
+    
+    /**
+     * @param {int} olZoom
+     * 
+     * @returns A VEZoom level, translated from the passed in olZoom
+     *          Returns null if null value is passed in
+     * @type int
+     */
+    getVEZoomFromOLZoom: function(olZoom) {
+        var zoom = null; 
+        if (olZoom != null) {
+            zoom = olZoom + 1;
+        }
+        return zoom;
+    },
+
+  //
+  // TRANSLATION: VELatLong <-> LonLat
+  //
+
+    /**
+     * @param {VELatLong} veLatLong
+     * 
+     * @returns An OpenLayers.LonLat, translated from the passed in VELatLong
+     *          Returns null if null value is passed in
+     * @type OpenLayers.LonLat
+     */
+    getOLLonLatFromVELatLong: function(veLatLong) {
+        var olLonLat = null;
+        if (veLatLong != null) {
+            olLonLat = new OpenLayers.LonLat(veLatLong.Longitude, 
+                                             veLatLong.Latitude);
+        }
+        return olLonLat;
+    },
+
+    /**
+     * @param {OpenLayers.LonLat} olLonLat
+     * 
+     * @returns A VELatLong, translated from the passed in OpenLayers.LonLat
+     *          Returns null if null value is passed in
+     * @type VELatLong
+     */
+    getVELatLongFromOLLonLat: function(olLonLat) {
+        var veLatLong = null;
+        if (olLonLat != null) {
+            veLatLong = new VELatLong(olLonLat.lat, olLonLat.lon);
+        }
+        return veLatLong;
+    },
+
+
+  //
+  // TRANSLATION: Pixel <-> OpenLayers.Pixel
+  //
+
+    /**
+     * @param {Pixel} pixel
+     * 
+     * @returns An OpenLayers.Pixel, translated from the passed in Pixel
+     *          Returns null if null value is passed in
+     * @type OpenLayers.Pixel
+     */
+    getOLPixelFromPixel: function(pixel) {
+        var olPixel = null;
+        if (pixel != null) {
+            olPixel = new OpenLayers.Pixel(pixel.x, pixel.y);
+        }
+        return olPixel;
+    },
+
+    /**
+     * @param {OpenLayers.Pixel} olPixel
+     * 
+     * @returns A Pixel, translated from the passed in OpenLayers.Pixel
+     *          Returns null if null value is passed in
+     * 
+     *          As it turns out, the only specifications we can see for the
+     *          VE-compatible Pixel is an x & y property, which every 
+     *          OpenLayers.Pixel has by default. So just leave it as-is.
+     * 
+     * @type GPoint
+     */
+    getGPointFromOLPixel: function(olPixel) {
+        return olPixel;
+    },
+
+  //
+  // TRANSLATION: VELatLongBounds <-> OpenLayers.Bounds
+  //
+
+    /**
+     * @param {VELatLongBounds} veLatLongBounds
+     * 
+     * @returns An OpenLayers.Bounds, translated from veLatLongBounds
+     *          Returns null if null value is passed in
+     * @type OpenLayers.Bounds
+     */
+    getOLBoundsFromVELatLongBounds: function(veLatLongBounds) {
+        var olBounds = null;
+        if (veLatLongBounds != null) {
+            var sw = veLatLongBounds.getSouthWest();
+            var ne = veLatLongBounds.getNorthEast();
+            olBounds = new OpenLayers.Bounds(sw.lng(), 
+                                             sw.lat(), 
+                                             ne.lng(), 
+                                             ne.lat() );
+        }
+        return olBounds;
+    },
+
+    /**
+     * @param {OpenLayers.Bounds} olBounds
+     * 
+     * @returns A VELatLongBounds, translated from olBounds
+     *          Returns null if null value is passed in
+     * @type VELatLongBounds
+     */
+    getVELatLongBoundsFromOLBounds: function(olBounds) {
+        var veLatLongBounds = null;
+        if (olBounds != null) {
+            var sw = new VELatLong(olBounds.bottom, olBounds.left);
+            var ne = new VELatLong(olBounds.top, olBounds.right);
+            veLatLongBounds = new VELatLongBounds(sw, ne);
+        }
+        return veLatLongBounds;
+    },
+
+    
 
     /** @final @type String */
     CLASS_NAME: "OpenLayers.Layer.VirtualEarth"