source: code/Website/open-flash-chart/charts/Elements/Star.as@ 7849

package charts.Elements {
        import charts.Elements.PointDotBase;
        import flash.display.BlendMode;
        import flash.display.Graphics;
        import flash.display.Sprite;
        
        public class Star extends PointDotBase {
                
                public function Star( index:Number, style:Object ) {
                        
                        super( index, style );
                        
                        this.visible = true;
                        
                        this.graphics.clear();
                        this.graphics.lineStyle( style.width, style.colour, 1);// style.alpha );
                        var rotation:Number = isNaN(style['rotation']) ? 0 : style['rotation'];
                        
                        this.drawStar( this.graphics, style['dot-size'], rotation );
                        
                        var haloSize:Number = style['halo-size']+style['dot-size'];
                        var s:Sprite = new Sprite();
                        s.graphics.lineStyle( 0, 0, 0 );
                        s.graphics.beginFill( 0, 1 );
                        this.drawStar(s.graphics, haloSize, rotation );
                        s.blendMode = BlendMode.ERASE;
                        s.graphics.endFill();
                        this.line_mask = s;
                        
                        this.attach_events();
                        
                }
                
                private function calcXOnCircle(radius:Number, degrees:Number):Number
                {
                        return radius * Math.cos(degrees / 180 * Math.PI);
                }
                
                private function calcYOnCircle(radius:Number, degrees:Number):Number
                {
                        return radius * Math.sin(degrees / 180 * Math.PI);
                }
                
                private function drawStar( graphics:Graphics, radius:Number, rotation:Number ):void 
                {
                        var angle:Number = 360 / 5;

                        // Start at top point (unrotated)
                        var degrees:Number = -90 + rotation;
                        for (var i:int = 0; i <= 5; i++)
                        {
                                var x:Number = this.calcXOnCircle(radius, degrees);
                                var y:Number = this.calcYOnCircle(radius, degrees);
                                
                                if (i == 0)
                                        graphics.moveTo(x, y);
                                else
                                        graphics.lineTo(x, y);
                                        
                                // Move 2 points clockwise
                                degrees += (2 * angle);
                        }
                }
        }
}