source: Dev/trunk/src/client/dojox/charting/action2d/Magnify.js

define(["dojo/_base/connect", "dojo/_base/declare", 
        "./PlotAction", "dojox/gfx/matrix", 
        "dojox/gfx/fx", "dojo/fx", "dojo/fx/easing"], 
        function(Hub, declare, PlotAction, m, gf, df, dfe){

        /*=====
        var __MagnifyCtorArgs = {
                // summary:
                //              Additional arguments for magnifying actions.
                // duration: Number?
                //              The amount of time in milliseconds for an animation to last.  Default is 400.
                // easing: dojo/fx/easing/*?
                //              An easing object (see dojo.fx.easing) for use in an animation.  The
                //              default is dojo.fx.easing.backOut.
                // scale: Number?
                //              The amount to magnify the given object to.  Default is 2.
        };
        =====*/
        
        var DEFAULT_SCALE = 2;

        return declare("dojox.charting.action2d.Magnify", PlotAction, {
                // summary:
                //              Create an action that magnifies the object the action is applied to.

                // the data description block for the widget parser
                defaultParams: {
                        duration: 400,  // duration of the action in ms
                        easing:   dfe.backOut,  // easing for the action
                        scale:    DEFAULT_SCALE // scale of magnification
                },
                optionalParams: {},     // no optional parameters

                constructor: function(chart, plot, kwArgs){
                        // summary:
                        //              Create the magnifying action.
                        // chart: dojox/charting/Chart
                        //              The chart this action belongs to.
                        // plot: String?
                        //              The plot to apply the action to. If not passed, "default" is assumed.
                        // kwArgs: __MagnifyCtorArgs?
                        //              Optional keyword arguments for this action.

                        // process optional named parameters
                        this.scale = kwArgs && typeof kwArgs.scale == "number" ? kwArgs.scale : DEFAULT_SCALE;

                        this.connect();
                },

                process: function(o){
                        // summary:
                        //              Process the action on the given object.
                        // o: dojox/gfx/shape.Shape
                        //              The object on which to process the magnifying action.
                        if(!o.shape || !(o.type in this.overOutEvents) ||
                                !("cx" in o) || !("cy" in o)){ return; }

                        // if spider deal only with circle
                        if(o.element == "spider_plot" || o.element == "spider_poly"){
                                return;
                        }

                        var runName = o.run.name, index = o.index, vector = [], anim, init, scale;

                        if(runName in this.anim){
                                anim = this.anim[runName][index];
                        }else{
                                this.anim[runName] = {};
                        }

                        if(anim){
                                anim.action.stop(true);
                        }else{
                                this.anim[runName][index] = anim = {};
                        }

                        if(o.type == "onmouseover"){
                                init  = m.identity;
                                scale = this.scale;
                        }else{
                                init  = m.scaleAt(this.scale, o.cx, o.cy);
                                scale = 1 / this.scale;
                        }

                        var kwArgs = {
                                shape:    o.shape,
                                duration: this.duration,
                                easing:   this.easing,
                                transform: [
                                        {name: "scaleAt", start: [1, o.cx, o.cy], end: [scale, o.cx, o.cy]},
                                        init
                                ]
                        };
                        if(o.shape){
                                vector.push(gf.animateTransform(kwArgs));
                        }
                        if(o.outline){
                                kwArgs.shape = o.outline;
                                vector.push(gf.animateTransform(kwArgs));
                        }
                        if(o.shadow){
                                kwArgs.shape = o.shadow;
                                vector.push(gf.animateTransform(kwArgs));
                        }

                        if(!vector.length){
                                delete this.anim[runName][index];
                                return;
                        }

                        anim.action = df.combine(vector);
                        if(o.type == "onmouseout"){
                                Hub.connect(anim.action, "onEnd", this, function(){
                                        if(this.anim[runName]){
                                                delete this.anim[runName][index];
                                        }
                                });
                        }
                        anim.action.play();
                }
        });
        
});