In a project I was on, I had a need to draw a circle in a certain amount of time and it proved to be a bit of a pain. So here is my code (with some ugly comments) that I used to do it.
Code after the jump.
Draw a Circle (6.7 KiB, 49 hits)
DocumentClass Code:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 | package { import flash.display.Sprite; import flash.display.Shape; import flash.display.LineScaleMode; import flash.display.CapsStyle; import flash.events.Event; import flash.utils.Timer; public class DrawACircle extends Sprite { //Circle Variables private var _speed:Number = 2; private var _timerTime:Number; //= (5000/360)*_speed; //19 <--- use to calculate based off how long you want it to take private var _theTimer:Timer; //= new Timer(_timerTime); private var _theCircle:Shape = new Shape(); private var _start_num:Number = new Number; //for timing private var _xPos:Number; private var _yPos:Number; private var _centerX:Number = 0; private var _centerY:Number = 0; private var _angle:Number = 270; private var _startAngle:Number; private var _radius:Number = 29; public function DrawACircle():void { addEventListener(Event.ADDED_TO_STAGE, init, false, 0, true); } private function init(e:Event):void { //_timerTime = Math.round((5000/360)*_speed); //19 _timerTime = 20; //change this value or use the calculated _timerTime at the top _theTimer = new Timer(_timerTime); _theTimer.addEventListener("timer", drawIt); //Circle _theCircle.x = stage.stageWidth/2; _theCircle.y = stage.stageHeight/2; addChild(_theCircle); initCircle(); //trace('_timerTime: ' + _timerTime); } //called to first create the circle, then called to create it again after the circle finishes drawing private function initCircle():void { var startTime:Date = new Date(); _start_num = startTime.getTime(); _theCircle.graphics.clear(); _theCircle.graphics.lineStyle(6, 0xFF0000,1,false,LineScaleMode.NORMAL,CapsStyle.NONE); _startAngle = _angle; //trace('initCircle ' + _startAngle); _xPos = (Math.cos(deg2rad(_startAngle)) * _radius) + _centerX; _yPos = (Math.sin(deg2rad(_startAngle)) * _radius) + _centerY; _theCircle.graphics.moveTo (_xPos, _yPos); //if (_theTimer.currentCount != 0) { //_theTimer.reset(); _theTimer.start(); //} } //called by the timer to draw the circle private function drawIt (e:Event):void { //trace('drawIt, _angle: ' + _angle + '; _xPos:' + _xPos + '; _yPos: ' + _yPos); _angle += _speed + .1; // TODO _xPos = (Math.cos(deg2rad(_angle)) * _radius) + _centerX; _yPos = (Math.sin(deg2rad(_angle)) * _radius) + _centerY; _theCircle.graphics.lineTo (_xPos,_yPos); if (_angle - 360 >= _startAngle) { _theTimer.stop(); //TODO //trace('drawIt _angle: ' + _angle); _angle = 270; //trace('drawIt _angle2: ' + _angle); var endTime:Date = new Date(); var total_num:Number = endTime.getTime() - _start_num; //trace('Loop met, total time: ' + total_num); initCircle(); } } //Helper utility to convert degrees to radians private function deg2rad (deg:Number):Number { return deg * Math.PI / 180; } } } |
