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Help with BlitMask and Throw Props

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I'm working on a mobile app that shows a list of players avatars, these avatars are made up of text, external swfs and other things. It's basically a big movie clip holding these objects.


Now, I'd like to be able to smoothly tween up/down this list using throw props.


I have all the functionality I want done, but the performance is not very good.


Am I doing something wrong?


This is my code:



function mouseDownHandler(event:MouseEvent):void
			y1 = y2 = container.y;
			t1 = t2 = getTimer();
			container.startDrag(false, new Rectangle(bounds.x, -99999, 0, 99999999));
			container.addEventListener(Event.ENTER_FRAME, enterFrameHandler);
			container.stage.addEventListener(MouseEvent.MOUSE_UP, mouseUpHandler);

		function enterFrameHandler(event:Event):void
			y2 = y1;
			t2 = t1;
			y1 = container.y;
			t1 = getTimer();

		function mouseUpHandler(event:MouseEvent):void
			container.stage.removeEventListener(MouseEvent.MOUSE_UP, mouseUpHandler);
			container.removeEventListener(Event.ENTER_FRAME, enterFrameHandler);
			var time:Number = (getTimer() - t2) / 500;
			var yVelocity:Number = (container.y - y2) / time;
			var yOverlap:Number = Math.max(0,container.height - bounds.height);
			ThrowPropsPlugin.to(container, {throwProps:{
			 y:{velocity:yVelocity, max:70, min:70, resistance:200}
			 }, onUpdate:Mask.update, ease:Strong.easeOut
			}, 10, 0.3, 1);

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From a cursory glance the code looks like a fairly straight-forward (and accurate) adaptation of the sample code on the ThrowProps page.

Are you getting poor performance on a particular device?

Have you tried setting smoothing to false on your BlitMask, do you see a big difference?

Have you tested the code from the ThrowProps page without any modifications on your device? does it run any differently than your modified version?


We've heard plenty of great reports from folks using ThrowProps, but there are many factors that can impact performance on mobile devices and it really isn't possible to know what can be wrong from just seeing a code fragment.


Based on what you have provided it is difficult to really know what is wrong. The best thing I can recommend to isolate the problem would be to create a throwProps sample with the least amount of technical overhead as possible ie, don't rely on externally loaded swfs, text or any other functionality. See how well you can get ThrowProps to run on its own, perhaps in the exercise of removing things it will be revealed what is the problem. It is very likely that the performance could be a hardware or AIR limitation and it simply can't handle ThrowProps :(

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Thanks. I got it working.


Turns out I wasn't setting up my layout properly, and was simply not correctly using the class.


Amazing performance once I figured it out properly - love green sock!

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Thanks for the folllow-up. It is great for us and other's to know that you are getting great performance with the GreenSock Tools.



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