source: Dev/trunk/src/client/dojox/dgauges/_circularUtils.js

define(function(){
        // module:
        //              dojox/dgauges/components/_circularUtils
        // summary:
        //              Internal circular utilities.
        // tags:
        //              private

        return {
                computeTotalAngle: function(start, end, orientation){
                        // summary:
                        //              Internal method.
                        // tags:
                        //              private
                        if(start == end){
                                return 360;
                        }else{
                                return this.computeAngle(start, end, orientation, 360);
                        }
                },
                
                modAngle: function(angle, base){
                        // summary:
                        //              Internal method.
                        // tags:
                        //              private
                        if(base == undefined){
                                base = 6.28318530718;
                        }
                        if(angle >= base){
                                do {
                                        angle -= base;
                                }
                                while (angle >= base);
                        }else{
                                while (angle < 0){
                                        angle += base;
                                }
                        }
                        return angle;
                },
                
                computeAngle: function(startAngle, endAngle, orientation, base){
                        // summary:
                        //              Internal method.
                        // tags:
                        //              private
                        if(base == undefined){
                                base = 6.28318530718;
                        }
                        
                        var totalAngle;
                        
                        if(endAngle == startAngle){
                                return base;
                        }
                        
                        if(orientation == "clockwise"){
                                if(endAngle < startAngle){
                                        totalAngle = base - (startAngle - endAngle);
                                }else{
                                        totalAngle = endAngle - startAngle;
                                }
                        }
                        else{
                                if(endAngle < startAngle){
                                        totalAngle = startAngle - endAngle;
                                }else{
                                        totalAngle = base - (endAngle - startAngle);
                                }
                        }
                        return this.modAngle(totalAngle, base);
                },
                
                toRadians: function(deg){
                        // summary:
                        //              Internal method.
                        // tags:
                        //              private
                        return deg * Math.PI / 180;
                },
                
                toDegrees: function(rad){
                        // summary:
                        //              Internal method.
                        // tags:
                        //              private
                        return rad * 180 / Math.PI;
                }
        }
});