Flash AS代码实例：仿贝塞尔曲线控制


本文中我们用Flash的AS代码来写一段实例，模仿设计软件中贝塞尔曲线的控制。 　　下面是完成效果：


用鼠标点击拖动灰色的方形锚点，即可看见曲线的变化（小心不要拖出画面了）
  AS代码如下：

//这个函数是用来绘制线条的 
function connect(){ 
this.clear() 
this.lineStyle(3,0x660000,100) 
this.moveTo(anchorOne._x,anchorOne._y) 
this.curveTo(controlOne._x,controlOne._y,anchorTwo._x,anchorTwo._y) 
updateAfterEvent() 
} 
//这个函数是用来绘制替代描点跟控制点的MC，就绘制一个正方形吧 
function createSquare(handle,side,offset){ 
if(offset==undefines){ 
  offset=0 
} 
with(handle){ 
  moveTo(offset,offset) 
  lineTo(offset,side) 
  lineTo(side,side) 
  lineTo(side,offset) 
  lineTo(offset,offset) 
  endFill() 
} 
} 
//这是用来控制描点跟控制点的移动，并且用延时，间隔一段时间调用一次绘制线条 
function setDraggable(handle){ 
handle.onPress=function(){ 
  clearInterval(_global.refreshScreen) 
  _global.refreshScreen=setInterval(this._parent,"connect",10) 
  this.startDrag(false) 
} 
handle.onRelease=function(){ 
  clearInterval(_global.refreshScreen) 
  this.stopDrag() 
} 
handle.onReleaseOutside=function(){ 
  clearInterval(_global.refreshScreen) 
  this.stopDrag() 
} 
} 
//建立描点 
anchorOne=createEmptyMovieClip("anchorPoint1",this.getNextHighestDepth()) 
anchorOne._x=anchorOne._y=50 
//填充 
anchorOne.beginFill(0xcccccc,100) 
//样式 
anchorOne.lineStyle(0,0x000000,100,false,false,"none","miter",2) 
//调用函数绘制成正方形 
createSquare(anchorOne,8,-8) 
//调用后方可拖动 
setDraggable(anchorOne) 
//另一个描点 
anchorTwo=createEmptyMovieClip("anchorPoint2",this.getNextHighestDepth()) 
anchorTwo._x=anchorTwo._y=250 
anchorTwo.beginFill(0xcccccc,100) 
anchorTwo.lineStyle(0,0x000000,100,false,false,"none","miter",2) 
createSquare(anchorTwo,8,-8) 
setDraggable(anchorTwo) 
//控制点 
controlOne=createEmptyMovieClip("control1",this.getNextHighestDepth()) 
controlOne._x=anchorTwo._x 
controlOne._y=anchorOne._y 
controlOne.beginFill(0xcccccc,100) 
controlOne.lineStyle(0,0x000000,100,false,false,"none","miter",2) 
createSquare(controlOne,8,-8) 
setDraggable(controlOne) 
//最后让线条一开始就显示出来 
connect()
　　复制粘贴到到吗层，测试即可看到效果。原文链接