ActionScript 3鼠绘

本文用AS3分别描绘了曲线、直线、圆、椭圆和矩形5种绘制方法，希望能给大家带来帮助！

（1）：曲线

知识点：

1、添加鼠标监听事件MouseEvent；

2、规定画布大小；

3、moveTo和lineTo；

4、绘制开始与结束判断。

代码：

var huabu:Sprite=new Sprite(); 

huabu.graphics.beginFill(0xFFFFFF); 

huabu.graphics.drawRect(20,20,510,360); 

huabu.graphics.endFill(); 

addChild(huabu); 

var _drawing:Boolean; 

var quxian:Sprite=new Sprite(); 

quxian.graphics.lineStyle( 2, 0xFF0000 ); 

huabu.addChild(quxian); 

_drawing = false; 

huabu.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); 

huabu.addEventListener( MouseEvent.MOUSE_MOVE,moving); 

huabu.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); 

stage.addEventListener(MouseEvent.MOUSE_UP,stopDrawing); 

function startDrawing( event:MouseEvent ):void { 

 quxian.graphics.moveTo( mouseX, mouseY ); 

 _drawing = true; 

} 

function moving( event:MouseEvent ):void { 

 if ( _drawing ) { 

  quxian.graphics.lineTo( mouseX, mouseY ); 

 } 

} 

function stopDrawing( event:MouseEvent ):void { 

 _drawing = false; 

}

（2）：直线

知识点：

1、添加鼠标监听事件MouseEvent；

2、规定画布大小；

3、moveTo和lineTo；

4、绘制开始与结束判断。

难点：

绘制多条直线

代码：

var huabu:Sprite=new Sprite(); 

huabu.graphics.beginFill(0xFFFFFF); 

huabu.graphics.drawRect(20,20,510,360); 

huabu.graphics.endFill(); 

addChild(huabu); 

var _drawing:Boolean=false; 

var zhixian:Sprite=new Sprite(); 

huabu.addChild(zhixian); 

var _color:Number=0xFF0000; 

var zx:int=1; 

var ys_x:Number; 

var ys_y:Number; 

huabu.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); 

huabu.addEventListener( MouseEvent.MOUSE_MOVE,moving); 

huabu.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); 

stage.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); 

function startDrawing( event:MouseEvent ):void { 

 ys_x=mouseX; 

 ys_y=mouseY; 

 _drawing = true; 

} 

function moving( event:MouseEvent ):void { 

 if (_drawing) { 

  huabu.removeChild(zhixian); 

  zhixian=new Sprite(); 

  zhixian.graphics.lineStyle( zx, _color ); 

  zhixian.graphics.moveTo(ys_x,ys_y); 

  zhixian.graphics.lineTo(mouseX,mouseY); 

  huabu.addChild(zhixian); 

 } 

} 

function stopDrawing( event:MouseEvent ):void { 

 zhixian=new Sprite(); 

 huabu.addChild(zhixian); 

 //没有以上两句，只能画一条直线 

 _drawing = false; 

}

（3）：圆

知识点：

1、添加鼠标监听事件MouseEvent；

2、绘制过程中显示半径（两点间的距离Point.distance(坐标1,坐标2)）；

3、drawCircle、moveTo和lineTo；

4、绘制开始与结束判断。

难点：

绘制多个圆

代码：

var _drawing:Boolean; 

var yuan:Sprite=new Sprite(); 

addChild(yuan); 

var banjing:Sprite=new Sprite(); 

addChild(banjing); 

var yuanxin_x:Number; 

var yuanxin_y:Number; 

var zuobiao1:Point; 

var zuobiao2:Point; 

var bj:Number; 

_drawing = false; 

stage.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); 

stage.addEventListener( MouseEvent.MOUSE_MOVE,yd); 

stage.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); 

function startDrawing( event:MouseEvent ):void { 

 yuanxin_x=mouseX;//鼠标按下的位置就是圆心的位置 

 yuanxin_y=mouseY; 

 _drawing = true; 

} 

function yd( event:MouseEvent ):void { 

 if ( _drawing ) { 

  zuobiao1 = new Point(yuanxin_x,yuanxin_y); 

  zuobiao2 = new Point(mouseX, mouseY); 

  bj= Point.distance(zuobiao1, zuobiao2);//显示两点之间的距离即为半径 

  removeChild(yuan); 

  yuan=new Sprite(); 

  yuan.graphics.lineStyle( 2, 0xFF0000 ); 

  yuan.graphics.drawCircle(yuanxin_x,yuanxin_y,bj); 

  addChild(yuan); 

  removeChild(banjing); 

  banjing=new Sprite(); 

  banjing.graphics.lineStyle(2,0xFF0000,0.5); 

  banjing.graphics.moveTo(yuanxin_x,yuanxin_y); 

  banjing.graphics.lineTo(mouseX,mouseY); 

  addChild(banjing); 

 } 

} 

function stopDrawing( event:MouseEvent ):void { 

 removeChild(banjing);//绘制结束时半径线消失 

 banjing=new Sprite();//每次画圆过程中都显示半径 

 addChild(banjing); 

 yuan=new Sprite();//可绘制多个圆 

 addChild(yuan); 

  

 _drawing = false; 

}

（4）：椭圆

知识点：

1、添加鼠标监听事件MouseEvent和键盘监听事件KeyboardEvent；

2、椭圆的宽与高；

3、drawEllipse；

4、绘制开始与结束判断；

5、按下Shift键绘制正圆。

难点：

按下Shift键绘制正圆

代码：

var _drawing:Boolean=false; 

var ellipse:Sprite=new Sprite(); 

addChild(ellipse); 

var kaishi_x:Number; 

var kaishi_y:Number; 

var w:Number; 

var h:Number; 

var _max:Number; 

stage.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); 

stage.addEventListener( MouseEvent.MOUSE_MOVE,moving); 

stage.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); 

function startDrawing( event:MouseEvent ):void { 

 kaishi_x=mouseX; 

 kaishi_y=mouseY; 

 _drawing = true; 

} 

function moving( event:MouseEvent ):void { 

 if (_drawing) { 

  w=mouseX-kaishi_x; 

  h=mouseY-kaishi_y; 

  removeChild(ellipse); 

  ellipse=new Sprite(); 

  ellipse.graphics.lineStyle( 2, 0xFF0000 ); 

  ellipse.graphics.drawEllipse(kaishi_x,kaishi_y,w,h); 

  addChild(ellipse); 

 } 

} 

function stopDrawing( event:MouseEvent ):void { 

 ellipse=new Sprite(); 

 addChild(ellipse); 

 _drawing = false; 

} 

stage.focus=this; 

stage.addEventListener(KeyboardEvent.KEY_DOWN, shift); 

function shift(event:KeyboardEvent):void { 

 if (event.charCode==0) { 

  if (_drawing) { 

   w=mouseX-kaishi_x; 

   h=mouseY-kaishi_y; 

   _max=Math.max(Math.abs(w),Math.abs(h)); 

   if (w<0 && h<0) { 

    w=-_max; 

    h=-_max; 

   } 

   if (w>0 && h>0) { 

    w=_max; 

    h=_max; 

   } 

   if (w<0 && h>0) { 

    w=-_max; 

    h=_max; 

   } 

   if (w>0 && h<0) { 

    w=_max; 

    h=-_max; 

   } 

   removeChild(ellipse); 

   ellipse=new Sprite(); 

   ellipse.graphics.lineStyle( 2, 0xFF0000 ); 

   ellipse.graphics.drawEllipse(kaishi_x,kaishi_y,w,h); 

   addChild(ellipse); 

  } 

 } 

}

（5）：矩形

知识点：

1、添加鼠标监听事件MouseEvent和键盘监听事件KeyboardEvent；

2、椭圆的宽与高；

3、drawRect；

4、绘制开始与结束判断；

5、按下Shift键绘制正方形。

难点：

按下Shift键绘制正方形

代码：

var _drawing:Boolean=false; 

var _drawrect:Sprite=new Sprite(); 

addChild(_drawrect); 

var yx_x:Number; 

var yx_y:Number; 

var w:Number; 

var h:Number; 

var _max:Number; 

stage.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); 

stage.addEventListener( MouseEvent.MOUSE_MOVE,moving); 

stage.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); 

function startDrawing( event:MouseEvent ):void { 

 yx_x=mouseX; 

 yx_y=mouseY; 

 _drawing = true; 

} 

function moving( event:MouseEvent ):void { 

 if (_drawing) { 

  w=mouseX-yx_x; 

  h=mouseY-yx_y; 

  removeChild(_drawrect); 

  _drawrect=new Sprite(); 

  _drawrect.graphics.lineStyle( 2, 0xFF0000 ); 

  _drawrect.graphics.drawRect(yx_x,yx_y,w,h); 

  addChild(_drawrect); 

 } 

} 

function stopDrawing( event:MouseEvent ):void { 

 _drawrect=new Sprite(); 

 addChild(_drawrect); 

 _drawing = false; 

} 

stage.focus=this; 

stage.addEventListener(KeyboardEvent.KEY_DOWN, shift); 

function shift(event:KeyboardEvent):void { 

 if (event.charCode==0) { 

  if (_drawing) { 

   _max=Math.max(Math.abs(w),Math.abs(h)); 

   if (w<0 && h<0) { 

    w=-_max; 

    h=-_max; 

   } 

   if (w>0 && h>0) { 

    w=_max; 

    h=_max; 

   } 

   if (w<0 && h>0) { 

    w=-_max; 

    h=_max; 

   } 

   if (w>0 && h<0) { 

    w=_max; 

    h=-_max; 

   } 

   removeChild(_drawrect); 

   _drawrect=new Sprite(); 

   _drawrect.graphics.lineStyle( 2, 0xFF0000 ); 

   _drawrect.graphics.drawRect(yx_x,yx_y,w,h); 

   addChild(_drawrect); 

  } 

 } 

}