actionscript-3 - 如何从手势点捏缩放图片as3

Question

我创建了一个图像对象并且能够放大 .但图像只能在图像的中心查看。那么如何放大手势点的图像？？

picture.addEventListener(TransformGestureEvent.GESTURE_ZOOM, onZoom);

function onZoom(e:TransformGestureEvent){
    picture.scaleX *= (e.scaleX+e.scaleY)/2;
    picture.scaleY *= (e.scaleX+e.scaleY)/2;
}

Answer 1

试试这个...

import flash.events.TransformGestureEvent;
import flash.ui.Multitouch;
import flash.ui.MultitouchInputMode;
import fl.motion.MatrixTransformer;

Multitouch.inputMode = MultitouchInputMode.GESTURE;
stage.addEventListener(TransformGestureEvent.GESTURE_ZOOM , onZoom);
function onZoom(event:TransformGestureEvent):void
{
    //trace(e.localX);
    var locX:Number=event.localX;
    var locY:Number=event.localY;
    var stX:Number=event.stageX;
    var stY:Number=event.stageY;
    var prevScaleX:Number=gambar.scaleX;
    var prevScaleY:Number=gambar.scaleY;
    var mat:Matrix;
    var externalPoint=new Point(stX,stY);
    var internalPoint=new Point(locX,locY);

    gambar.scaleX *= event.scaleX;
    gambar.scaleY *= event.scaleY;

    if(event.scaleX > 1 && gambar.scaleX > 6){
    gambar.scaleX=prevScaleX;
    gambar.scaleY=prevScaleY;
    }

    if(event.scaleY > 1 && gambar.scaleY > 6){
    gambar.scaleX=prevScaleX;
    gambar.scaleY=prevScaleY;
    }

    if(event.scaleX < 1.1 && gambar.scaleX < 1){
    gambar.scaleX=prevScaleX;
    gambar.scaleY=prevScaleY;
    }

    if(event.scaleY < 1.1 && gambar.scaleY < 1){
    gambar.scaleX=prevScaleX;
    gambar.scaleY=prevScaleY;

    }
    mat=gambar.transform.matrix.clone();
    MatrixTransformer.matchInternalPointWithExternal(mat,internalPoint,externalPoint);
    gambar.transform.matrix=mat;
}

gambar.addEventListener(MouseEvent.MOUSE_DOWN, f_begin);
gambar.addEventListener(MouseEvent.MOUSE_UP, f_end);
function f_begin(e:MouseEvent):void
{
    gambar.startDrag(); 
}
function f_end(e:MouseEvent):void
{
    gambar.stopDrag();
}

顺便说一句，你的照片很可爱..:D