// forked from dkgkAs's サイン・コサインを使った円運動 /** * サイン・コサインを使った円運動 * http://d.hatena.ne.jp/ActionScript/20090412/as3_math_sin_cos */ package { import flash.display.Sprite; import flash.events.Event; import flash.events.MouseEvent; import flash.events.TextEvent; import flash.text.TextField; import flash.text.TextFieldAutoSize; import flash.text.TextFormat; [SWF(width = 465, height = 465, backgroundColor = 0xffffff, frameRate = 30)] public class Main extends Sprite { private var _scx:Number; private var _scy:Number; private var _angle:Number = 0; // 角度 private var _change:Number = 1; // 増やす角度 private var _radius:Number = 150; // 半径 private var _ball:Sprite; private var _gsp:Sprite; // ガイド private var _tf:TextField; private var _flag:Boolean = true; public function Main():void { _scx = stage.stageWidth * 0.5; _scy = stage.stageHeight * 0.5; setup(); this.stage.addEventListener(Event.ENTER_FRAME, draw); this.stage.addEventListener(MouseEvent.CLICK, goAndStop); } private function setup():void { var circle:Sprite = new Sprite(); circle.graphics.lineStyle(1, 0x0, 1); circle.graphics.drawCircle(0, 0, _radius); circle.graphics.beginFill(0x0, 1); circle.graphics.drawCircle(0, 0, 3); circle.graphics.endFill(); circle.x = _scx; circle.y = _scy; circle.alpha = 0.3; this.stage.addChild(circle); var line:Sprite = new Sprite(); line.graphics.lineStyle(1, 0x0, 1); line.graphics.moveTo(_scx, 0); line.graphics.lineTo(_scx, stage.stageHeight); line.graphics.moveTo(0, _scy); line.graphics.lineTo(stage.stageWidth, _scy); line.alpha = 0.3; this.stage.addChild(line); _ball = new Sprite(); _ball.graphics.beginFill(0x336699, 0.7); _ball.graphics.drawCircle(0, 0, 7); _ball.graphics.endFill(); _ball.x = _scx + _radius; _ball.y = _scy; this.stage.addChild(_ball); _gsp = new Sprite(); this.stage.addChild(_gsp); var tfmt:TextFormat = new TextFormat("Arial", 12, 0x0); _tf = new TextField(); _tf.defaultTextFormat = tfmt; _tf.autoSize = TextFieldAutoSize.LEFT; this.stage.addChild(_tf); } private function goAndStop(event:MouseEvent):void { if (_flag) { this.stage.removeEventListener(Event.ENTER_FRAME, draw); } else { this.stage.addEventListener(Event.ENTER_FRAME, draw); } _flag = !_flag; } private function draw(event:Event):void { // 円運動の計算 var radian:Number = _angle * Math.PI / 180; // 度をラジアンに変換 _ball.x = _scx + _radius * Math.cos(radian); _ball.y = _scy + _radius * Math.sin(radian); _angle += _change; _angle %= 360; // 以下ガイドの描画 _gsp.graphics.clear(); // 斜辺(半径) _gsp.graphics.lineStyle(2, 0x00ff00, 1); _gsp.graphics.moveTo(_scx, _scy); _gsp.graphics.lineTo(_ball.x, _ball.y); // 対辺 _gsp.graphics.lineStyle(2, 0xff0000, 1); _gsp.graphics.moveTo(_ball.x, _ball.y); _gsp.graphics.lineTo(_ball.x, _scy); // 隣辺 _gsp.graphics.lineStyle(2, 0x0000ff, 1); _gsp.graphics.moveTo(_ball.x, _scx); _gsp.graphics.lineTo(_scx, _scy); // 数値表示 _tf.text = "画面クリックで再生/停止\n\n" + "角度: " + _angle + "\n" + "隣辺: " + _radius * Math.cos(radian) + " px\n" + "対辺: " + _radius * Math.sin(radian) + " px\n\n" + "ラジアン: " + radian + "\n" + "コサイン: " + Math.cos(radian) + "\n" + "サイン: " + Math.sin(radian) + "\n\n" + "半径: " + _radius + " px\n"; } } }