AS3运动学基础-正弦运动

package 
{
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.events.MouseEvent;
	
	/**
	 * ...
	 * @author hacker47
	 */
	public class Main extends Sprite 
	{
		private var angle:Number = 0;
		private var speed:Number = .05;
		private var range:Number = 200;
		private var vx:Number = 1;
		
		private var startx:Number=100;
		private var starty:Number=300;
		
		
		public function Main():void 
		{
			if (stage) init();
			else addEventListener(Event.ADDED_TO_STAGE, init);
		}
		
		private function init(e:Event = null):void 
		{
			removeEventListener(Event.ADDED_TO_STAGE, init);
			// entry point
			this.graphics.lineStyle(2,0xff0000,1,true);
			this.graphics.moveTo(startx, starty);
			addEventListener(Event.ENTER_FRAME, function running(e:Event):void {
				var dx:Number = startx + vx;
				var dy:Number = starty+Math.sin(angle) * range;
				angle += speed;
				graphics.lineTo(dx, dy);
				startx = dx;
				trace(angle);
			});
		}
		
	}
	
}

package 
{
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.events.MouseEvent;
	
	/**
	 * ...
	 * @author hacker47
	 */
	public class Main1 extends Sprite 
	{
		private var angle:Number = 0;
		private var speed:Number = .05;
		private var range:Number = 200;
		private var vx:Number = 1;
		
		private var startx:Number=100;
		private var starty:Number=300;
		
		
		public function Main1():void 
		{
			if (stage) init();
			else addEventListener(Event.ADDED_TO_STAGE, init);
		}
		
		private function init(e:Event = null):void 
		{
			removeEventListener(Event.ADDED_TO_STAGE, init);
			// entry point
			this.graphics.lineStyle(2,0xff0000,1,true);
			this.graphics.moveTo(startx, starty);
			addEventListener(Event.ENTER_FRAME, function running(e:Event):void {
				var dx:Number = startx + vx;
				var dy:Number = starty+Math.sin(angle) * range;
				angle += speed;
				graphics.lineTo(dx, dy);
				startx = dx;
				if ((angle * 180 / Math.PI) > 360) {
					range-= 30;
					angle = 0;
					trace("一个周期");
				}
			});
		}
		
	}
	
}

package 
{
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.events.MouseEvent;
	
	/**
	 * ...
	 * @author hacker47
	 */
	public class Main2 extends Sprite 
	{
		private var angle:Number = 0;
		private var speed:Number = .05;
		private var range:Number = 200;
		private var vx:Number = 2;
		
		private var startx:Number=100;
		private var starty:Number=300;
		
		
		public function Main2():void 
		{
			if (stage) init();
			else addEventListener(Event.ADDED_TO_STAGE, init);
		}
		
		private function init(e:Event = null):void 
		{
			removeEventListener(Event.ADDED_TO_STAGE, init);
			// entry point
			this.graphics.lineStyle(2,0xff0000,1,true);
			this.graphics.moveTo(startx, starty);
			addEventListener(Event.ENTER_FRAME, function running(e:Event):void {
				var dx:Number = startx + vx;
				var sin:Number = Math.sin(angle);
				if (sin > 0) sin *= -1;
				var dy:Number = starty+sin * range;
				angle += speed;
				graphics.lineTo(dx, dy);
				startx = dx;
				if ((angle * 180 / Math.PI) > 180) {
					range-= 30;
					angle = 0;
					trace("一个周期");
					if (range < 0) {
						removeEventListener(Event.ENTER_FRAME, running);
					}
				}
			});
		}
		
	}
	
}