WebGL MapRender - initial not finished version.

src/ol/renderer/WebGL.js

@@ -0,0 +1,130 @@
+/**
+ * @fileoverview WebGL based MapRenderer drawing all the supplied layers in OpenGL
+ */
+
+goog.provide('ol.renderer.WebGL');
+
+goog.require('ol.renderer.MapRenderer');
+goog.require('ol.layer.Layer');
+goog.require('ol.Loc');
+
+/**
+ * Initialization of the native WebGL renderer (canvas, context, layers)
+ * @constructor
+ * @param {!Element} target
+ * @extends {ol.renderer.MapRenderer}
+ */
+ol.renderer.WebGL = function(target) {
+    
+    /** @type {!Element} */
+    var canvasEl = goog.dom.createDom('canvas',
+        {style: 'width:100%;height:100%;'});
+
+
+    var upgradeRedirector = function() {
+      /** @type {!Element} */
+      var upgradeLinkEl = goog.dom.createDom('a',
+          {style: 'font-size:110%;display:block;width:100%;top:50%;' +
+                'position:relative;text-align:center;color:#800000;' +
+                'text-shadow:rgba(0,0,0,0.4) 0 0 6px;',
+            href: 'http://get.webgl.org/'
+          }, 'You need a WebGL-enabled browser to run this application.');
+      goog.dom.append(/** @type {!Element} */ (divEl), upgradeLinkEl);
+    };
+
+    /**
+     * @type {!we.gl.Context}
+     */
+    this.context = new we.gl.Context(canvasEl, null, upgradeRedirector);
+
+    if (!goog.isDefAndNotNull(this.context)) return;
+    
+    goog.base(this, target);
+    
+    /**
+     * @type Array.<ol.renderer.LayerRenderer>
+     * @private
+     */
+    this.renderers_ = [];
+    
+};
+
+goog.inherits(ol.renderer.WebGL, ol.renderer.MapRenderer);
+
+/**
+ * @param {Array.<ol.layer.Layer>} layers
+ * @param {ol.Loc} center
+ * @param {number} resolution
+ */
+ol.renderer.WebGL.prototype.draw = function(layers, center, resolution) {
+};
+
+/**
+ * @param {ol.layer.Layer} layer
+ */
+ol.renderer.WebGL.prototype.getRenderer = function(layer) {
+    function finder(candidate) {
+        return candidate.getLayer() === layer;
+    }
+    return goog.array.find(this.renderers_, finder);
+};
+
+/**
+ * @param {ol.layer.Layer} layer
+ */
+ol.renderer.WebGL.prototype.createRenderer = function(layer) {
+};
+
+/**
+ * List of preferred renderer types.  Layer renderers have a getType method
+ * that returns a string describing their type.  This list determines the 
+ * preferences for picking a layer renderer.
+ *
+ * @type {Array.<string>}
+ */
+ol.renderer.WebGL.preferredRenderers = ["svg", "canvas", "vml"];
+
+/**
+ * @param {ol.layer.Layer} layer
+ * @returns {Function}
+ */
+ol.renderer.WebGL.prototype.pickRendererType = function(layer) {
+    // maps candidate renderer types to candidate renderers
+    var types = {};
+
+    function picker(Candidate) {
+        var supports = Candidate.isSupported() && Candidate.canRender(layer);
+        if (supports) {
+            types[Candidate.getType()] = Candidate;
+        }
+        return supports;
+    }
+    var Candidates = goog.array.some(ol.renderer.WebGL.registry_, picker);
+    
+    // check to see if any preferred renderers are available
+    var preferences = ol.renderer.WebGL.preferredRenderers;
+
+    var Renderer;
+    for (var i=0, ii=preferences.length; i<ii; ++i) {
+        Renderer = preferences[i];
+        if (Renderer) {
+            break;
+        }
+    }
+    
+    // if we didn't find any of the preferred renderers, use the first
+    return Renderer || Candidates[0] || null;
+};
+
+/**
+ * @type {Array.<Function>}
+ * @private
+ */
+ol.renderer.WebGL.registry_ = [];
+
+/**
+ * @param {Function} Renderer
+ */
+ol.renderer.WebGL.register = function(Renderer) {
+    ol.renderer.WebGL.registry_.push(Renderer);
+};