// forked from summerTree's flash on 2010-3-16 package { import flash.display.*; import flash.events.*; import flash.geom.Point; import flash.filters.GlowFilter; [SWF(backgroundColor="0xffffff", frameRate="25")] //绘制一棵树 //@author 夏天的树人 public class Main extends Sprite { private var shape:Shape; private var source:BitmapData; public function Main() { shape = new Shape(); //addChild(shape); source = new BitmapData(465, 465, false, 0xffffff); addChild(new Bitmap(source)); this.addEventListener(Event.ENTER_FRAME, onEnterFrame); } private function onEnterFrame(e:Event):void { shape.graphics.clear(); creatTree(shape.graphics, 232, 465, 90, 180, 5); creatTree(shape.graphics, 232, 465, 45, 100, 4); creatTree(shape.graphics, 232, 465, 135, 100, 4); step += (Math.PI/80) % Math.PI; source.fillRect(source.rect, 0xffffff); source.draw(shape); } private var step:Number = 0.0; private static const toRadian:Number = Math.PI / 180; //绘图对象，基本坐标px,py,角度，偏移长度，数量 private function creatTree(g:Graphics,px:Number,py:Number,angle:Number,len:Number,n:int):void { if (n>0) { angle += 3 * Math.cos(step) - 2; var x1:Number = px+0.1*len*Math.cos(angle * toRadian); var y1:Number = py-0.1*len*Math.sin(angle * toRadian); var x2:Number = px+len*Math.cos(angle * toRadian); var y2:Number = py-len*Math.sin(angle * toRadian); drawLine(g,n-1,px,py,x2,y2); var a_l:Number = angle + 30; var a_r:Number = angle - 30; len = len * 2/3; creatTree(g, x2, y2, angle - 3 * Math.sin(step), len, n-1); creatTree(g, x1, y1, a_l, len*2/3, n-1); creatTree(g, x1, y1, a_r, len*2/3, n-1); creatTree(g, x2, y2, a_l, len*2/3, n-1); creatTree(g, x2, y2, a_r, len*2/3, n-1); } } //绘制线 private function drawLine(g:Graphics,n:int,x1:Number,y1:Number,x2:Number,y2:Number):void { g.lineStyle(n,0x006600); g.moveTo(x1,y1); g.lineTo(x2,y2); } } }