Is there an optimal way to render images in cocoa? Im using setNeedsDisplay

Posted by Edward An on Stack Overflow See other posts from Stack Overflow or by Edward An
Published on 2009-08-17T15:11:10Z Indexed on 2014/06/07 21:25 UTC
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cocoa-touch

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cocoa

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uiimage

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drawing

Currently, any time I manually move a UIImage (via handling the touchesMoved event) the last thing I call in that event is [self setNeedsDisplay], which effectively redraws the entire view.

My images are also being animated, so every time a frame of animation changes, i have to call setNeedsDisplay.

I find this to be horrific since I don't expect iphone/cocoa to be able to perform such frequent screen redraws very quickly.

Is there an optimal, more efficient way that I could be doing this? Perhaps somehow telling cocoa to update only a particular region of the screen (the rect region of the image)?

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