Files
openlayers/lib/OpenLayers/Layer/Canvas.js
crschmidt 786c2a20fb Change files to point to repository-license. Part of build process will now
be to change the licensing terms in the final build.


git-svn-id: http://svn.openlayers.org/trunk/openlayers@1721 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
2006-10-24 18:16:39 +00:00

121 lines
3.5 KiB
JavaScript

/* 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
*
* @requires OpenLayers/Layer.js
*/
OpenLayers.Layer.Canvas = OpenLayers.Class.create();
OpenLayers.Layer.Canvas.prototype =
OpenLayers.Class.inherit( OpenLayers.Layer, {
/** Canvas layer is never a base layer.
*
* @type Boolean
*/
isBaseLayer: false,
isFixed: true,
/** internal marker list
* @type Array(OpenLayers.Marker) */
canvas: null,
lines: new Array(),
/**
* @constructor
*
* @param {String} name
* @param {Object} options Hashtable of extra options to tag onto the layer
*/
initialize: function(name, options) {
OpenLayers.Layer.prototype.initialize.apply(this, arguments);
},
/**
*
*/
destroy: function() {
// xxx actually destroy the canvas to scavenge ram?
canvas = null;
OpenLayers.Layer.prototype.destroy.apply(this, arguments);
},
/**
* @param {OpenLayers.Bounds} bounds
* @param {Boolean} zoomChanged
* @param {Boolean} dragging
*/
moveTo:function(bounds, zoomChanged, dragging) {
OpenLayers.Layer.prototype.moveTo.apply(this, arguments);
this.redraw();
},
setStrokeColor: function(color) {
var ctx = this.canvas.getContext("2d");
ctx.strokeStyle = color;
},
setStrokeWidth: function(width) {
var ctx = this.canvas.getContext("2d");
ctx.lineWidth = width;
},
setAlpha: function(alpha) {
var ctx = this.canvas.getContext("2d");
ctx.globalAlpha = alpha;
},
/**
*
*/
clearCanvas: function() {
if(this.canvas != null) {
this.canvas.getContext("2d").clearRect(0,0,this.map.getSize().w, this.map.getSize().h);
// xxx use real width and height
}
},
drawLine: function(start, end) {
var ctx = this.canvas.getContext("2d");
this.addLine(start, end);
this.lines.push(new Array(start,end, ctx.strokeStyle, ctx.lineWidth, ctx.globalAlpha));
},
addLine: function(start, end) {
var ctx = this.canvas.getContext("2d");
var startpx = this.map.getPixelFromLonLat(start);
var endpx = this.map.getPixelFromLonLat(end);
ctx.beginPath();
ctx.moveTo(startpx.x, startpx.y);
ctx.lineTo(endpx.x, endpx.y);
ctx.closePath();
ctx.stroke();
},
/** clear all the marker div's from the layer and then redraw all of them.
* Use the map to recalculate new placement of markers.
*/
redraw: function() {
// xxx rebuild the canvas if smaller than the view
// xxx may wish to overside the canvas with overflow=hidden by default
if(!this.canvas) {
this.canvas = document.createElement("CANVAS");
this.canvas.setAttribute("width",this.map.getSize().w);
this.canvas.setAttribute("height",this.map.getSize().h);
this.div.appendChild(this.canvas);
} else {
this.clearCanvas();
}
for(var i=0; i < this.lines.length; i++) {
this.setStrokeColor(this.lines[i][2]);
this.setStrokeWidth(this.lines[i][3]);
this.setAlpha(this.lines[i][4]);
this.addLine(this.lines[i][0], this.lines[i][1]);
}
},
/** @final @type String */
CLASS_NAME: "OpenLayers.Layer.Canvas"
});