source: code/Website/open-flash-chart/charts/Arrow.as

package charts {
        import flash.display.Sprite;
        import flash.geom.Point;
        import string.Utils;
        
        public class Arrow extends Base {
                
                private var style:Object;
                
                public function Arrow( json:Object )
                {
                        this.style = {
                                start:                          [],
                                end:                            [],
                                colour:                         '#808080',
                                alpha:                          0.5,
                                'barb-length':          20
                                
                        };
                        
                        object_helper.merge_2( json, this.style );
                        
                        this.style.colour               = string.Utils.get_colour( this.style.colour );
                        
//                      for each ( var val:Object in json.values )
//                              this.style.points.push( new flash.geom.Point( val.x, val.y ) );
                }
                
                public override function resize( sc:ScreenCoordsBase ): void {
                        
                        this.graphics.clear();
                        this.graphics.lineStyle(1, this.style.colour, 1);
                        
                        this.graphics.moveTo(
                                sc.get_x_from_val(this.style.start.x),
                                sc.get_y_from_val(this.style.start.y));
                        
                        var x:Number = sc.get_x_from_val(this.style.end.x);
                        var y:Number = sc.get_y_from_val(this.style.end.y);
                        this.graphics.lineTo(x, y);
                        
                        var angle:Number = Math.atan2(
                                sc.get_y_from_val(this.style.start.y) - y,
                                sc.get_x_from_val(this.style.start.x) - x
                                );
                
                        var barb_length:Number = this.style['barb-length'];
                        var barb_angle:Number = 0.34;

                        //first point is end of one barb
                        var a:Number = x + (barb_length * Math.cos(angle - barb_angle));
                        var b:Number = y + (barb_length * Math.sin(angle - barb_angle));

                        //final point is end of the second barb
                        var c:Number = x + (barb_length * Math.cos(angle + barb_angle));
                        var d:Number = y + (barb_length * Math.sin(angle + barb_angle));

                        this.graphics.moveTo(x, y);
                        this.graphics.lineTo(a, b);
                        
                        this.graphics.moveTo(x, y);
                        this.graphics.lineTo(c, d);
                        
                }
        }
}