Merge vector-2.4 branch back to trunk.

svn merge sandbox/vector-2.4/@2307 sandbox/vector-2.4/@HEAD trunk/openlayers/ git-svn-id: http://svn.openlayers.org/trunk/openlayers@2803 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
2007-03-16 13:23:56 +00:00
parent 8b9d974dc2
commit 3ca974acec
159 changed files with 10193 additions and 343 deletions
@@ -0,0 +1,151 @@
+/* Copyright (c) 2006 MetaCarta, Inc., published under a modified BSD license.
+ * See http://svn.openlayers.org/trunk/openlayers/repository-license.txt 
+ * for the full text of the license. */
+
+/**
+ * @class Renderer is the base class for all renderers.
+ *
+ * This is based on a merger code written by Paul Spencer and Bertil Chapuis.
+ * It is largely composed of virtual functions that are to be implemented
+ * in technology-specific subclasses, but there is some generic code too.
+ * 
+ * The functions that *are* implemented here merely deal with the maintenance
+ *  of the size and extent variables, as well as the cached 'resolution' 
+ *  value. 
+ * 
+ * A note to the user that all subclasses should use getResolution() instead
+ *  of directly accessing this.resolution in order to correctly use the 
+ *  cacheing system.
+ *
+ */
+OpenLayers.Renderer = OpenLayers.Class.create();
+OpenLayers.Renderer.prototype = 
+{
+    /** @type DOMElement */
+    container: null,
+    
+    /** @type OpenLayers.Bounds */
+    extent: null,
+    
+    /** @type OpenLayers.Size */
+    size: null,
+    
+    /** cache of current map resolution
+     * @type float */
+    resolution: null,
+    
+    /** Reference to the map -- this is set in Vector's setMap()
+     * @type OpenLayers.Map */
+    map: null,
+    
+    /**
+     * @constructor
+     * 
+     * @param {String} containerID
+     */
+    initialize: function(containerID) {
+        this.container = $(containerID);
+    },
+    
+    /**
+     * 
+     */
+    destroy: function() {
+        this.container = null;
+        this.extent = null;
+        this.size =  null;
+        this.resolution = null;
+        this.map = null;
+    },
+
+    /**
+     * This should be overridden by specific subclasses
+     * 
+     * @returns Whether or not the browser supports the VML renderer
+     * @type Boolean
+     */
+    supported: function() {
+        return false;
+    },    
+    
+    /**
+     * Set the visible part of the layer.
+     *
+     * Resolution has probably changed, so we nullify the resolution 
+     * cache (this.resolution) -- this way it will be re-computed when 
+     * next it is needed.
+     *
+     * @param {OpenLayers.Bounds} extent
+     */
+    setExtent: function(extent) {
+        this.extent = extent.clone();
+        this.resolution = null;
+    },
+    
+    /**
+     * Sets the size of the drawing surface.
+     * 
+     * Resolution has probably changed, so we nullify the resolution 
+     * cache (this.resolution) -- this way it will be re-computed when 
+     * next it is needed.
+     *
+     * @param {OpenLayers.Size} size
+     */
+    setSize: function(size) {
+        this.size = size.clone();
+        this.resolution = null;
+    },
+    
+    /** Uses cached copy of resolution if available to minimize computing
+     * 
+     * @returns The current map's resolution
+     * @type float
+     */
+    getResolution: function() {
+        this.resolution = this.resolution || this.map.getResolution();
+        return this.resolution;
+    },
+    
+    /** 
+     * virtual function
+     * 
+     * Draw a geometry on the specified layer.
+     *
+     * @param geometry {OpenLayers.Geometry}
+     * @param style {Object}
+     */
+    drawGeometry: function(geometry, style) {},
+        
+    /**
+     * virtual function
+     *
+     * Clear all vectors from the renderer
+     *
+     */    
+    clear: function() {},
+
+    /**
+     * virtual function
+     * 
+     * Returns a geometry from an event that happened on a layer.  
+     * How this happens is specific to the renderer.
+     * 
+     * @param evt {OpenLayers.Event}
+     *
+     * @returns A geometry from an event that happened on a layer
+     * @type OpenLayers.Geometry
+     */
+    getGeometryFromEvent: function(evt) {},
+    
+    /**
+     * virtual function
+     * 
+     * Remove a geometry from the renderer (by id)
+     * 
+     * @param geometry {OpenLayers.Geometry}
+     */
+    eraseGeometry: function(geometry) {},
+        
+    /** @final @type String */
+    CLASS_NAME: "OpenLayers.Renderer"
+};