How to drag an image to move it smoothly on screen, with ActionScript?

Question

I was thinking this is a simple task, but I\'m wrong.

I used a sprite to display an image, and when user drag it(MOUSE_DOWN and MOUSE_MOVE), I got the position in

Answer 1

You must use a high framerate to have smooth movement. The optimal framerate is 60fps because it is the default for most LCD monitors.

I don't have the code under my hand so I put the code here (not tested)

yourClip.addeventListenner(MouseEvent.MOUSE_DOWN, startDrag);

function startDrag(e:MouseEvent = null):void{
    // record positon of the mouse relative to the clip
    deltaX=stage.mouseX-yourClip.x;
    deltaY=stage.mouseY-yourClip.y;
    // attach on mouse move event
    yourClip.addeventListenner(MouseEvent.MOUSE_MOVE, updateDrag);
    // attach stop event (on Stage)
    Stage.addeventListenner(MouseEvent.MOUSE_UP, stopDrag);
    }
function updateDrag(e:MouseEvent = null):void{
    yourClip.x=stage.mouseX-deltaX
    yourClip.y=stage.mouseY-deltaY
}

function stopDrag(e:MouseEvent = null):void{
   yourClip.removeEventListenner(MouseEvent.MOUSE_MOVE, updateDrag);
   stage.removeEventListenner(MouseEvent.MOUSE_UP, stopDrag);
}