AS3盤旋舞臺

Question

我試圖讓閃光燈從舞臺中央畫出一條線，並在舞臺周圍增加。不知道我會用什麼數學來做到這一點。到目前爲止，我的觀點已經到了一定程度，但不知道如何改變這一點，以便圍繞我的舞臺的任何尺寸展開。

到目前爲止，我有這樣的：

var linetox=0; 
var linetoy=0; 
var _stage=this; 
var _stage_center_x = stage.stageWidth/2; 
var _stage_center_y = stage.stageHeight/2; 
trace(_stage_center_x); 
function enterframe(e:Event):void { 
    linetox+=10; 
    linetoy+=10; 
    var lineDrawing:MovieClip = new MovieClip(); 
    this.addChild(lineDrawing); 
    lineDrawing.graphics.lineStyle(1); 
    lineDrawing.graphics.moveTo(_stage_center_x,_stage_center_y);///This is where we start drawing 
    lineDrawing.graphics.lineTo(linetox, linetoy); 
} 
this.addEventListener(Event.ENTER_FRAME, enterframe); 

這顯然移動線再降的目的地的結局，只是想獲得它繪製在屏幕上（如時鐘）

Answer 1

var center:Point = new Point(stage.stageWidth/2, stage.stageHeight/2); 
var radius:Number = 200; 
this.graphics.lineStyle(1, 0x000000, 1); 

addEventListener(Event.ENTER_FRAME, drawCirc); 

var _x:Number; 
var _y:Number; 
var _angle = -180; 
var _rads = 0; 
var rad_conversion:Number = Math.PI/180; 

function drawCirc($evt:Event) { 
    _rads = _angle * rad_conversion; 
    _x = radius * Math.cos(_rads) + center.x; 
    _y = radius * Math.sin(_rads) + center.y; 
    if (_angle == -180) { 
     this.graphics.moveTo(_x, _y); 
    } else { 
     this.graphics.lineTo(_x, _y); 
    } 
    _angle ++; 
    if (_angle >= 181) { 
     removeEventListener(Event.ENTER_FRAME, drawCirc); 
    } 
}