source: Dev/trunk/src/client/dojox/dgauges/CircularGauge.js @ 532

define(["dojo/_base/declare", "dojo/dom-geometry", "dojox/gfx", "./GaugeBase"], function(declare, domGeom, gfx, GaugeBase){
        return declare("dojox.dgauges.CircularGauge", GaugeBase, {
                // summary:
                //              The base class for circular gauges.
                //              You can create custom circular or semi-circular gauges by extending this class.
                //              See dojox.dgauges.components.default.CircularLinearGauge.js for an example of circular gauge.
                
                _transformProperties: null,
                
                refreshRendering: function(){
                        if(this._widgetBox.w <= 0 || this._widgetBox.h <= 0){
                                return;
                        }
                        
                        for(var key in this._elementsIndex){
                                this._elementsRenderers[key] = this._elementsIndex[key].refreshRendering();
                        }
                        
                        // Maximize the drawing area and center the gauge
                        var bb = this._computeBoundingBox(this._gfxGroup);
                        
                        var naturalRatio = (bb.x + bb.width) / (bb.y + bb.height);
                        var widgetWidth = this._widgetBox.w;
                        var widgetHeight = this._widgetBox.h;
                        var widgetRatio = this._widgetBox.w / this._widgetBox.h;
                        
                        var xpos = 0;
                        var ypos = 0;
                        var h = 0;
                        var w = 0;
                        if(naturalRatio > widgetRatio){
                                w = widgetWidth;
                                h = w / naturalRatio;
                                ypos = (widgetHeight - h) / 2;
                        }else{
                                h = widgetHeight;
                                w = h * naturalRatio;
                                xpos = (widgetWidth - w) / 2;
                        }
                        var scaleFactor = Math.max(w / (bb.x + bb.width), h / (bb.y + bb.height));
                        this._transformProperties = {scale:scaleFactor, tx:xpos, ty:ypos};
                        this._gfxGroup.setTransform([gfx.matrix.scale(scaleFactor), gfx.matrix.translate(xpos / scaleFactor, ypos / scaleFactor)]);
                },
                
                _gaugeToPage: function(px, py){
                        // summary:
                        //              Internal method.
                        // tags:
                        //              private
                        if(this._transformProperties){
                                var np = domGeom.position(this.domNode, true);
                                return {x: np.x + px * this._transformProperties.scale + this._transformProperties.tx, y: np.y + py * this._transformProperties.scale + this._transformProperties.ty};
                        }else{
                                return null;
                        }
                }
        });
});