Draw part of the content of a CGLayer
I have CGLayerRef which is updated periodically, I also have a CGRect indicates which part of the CGLayer got updated.  Is there any way I can draw only the updated area of the CGLayer to the targeted CGContext.  The CGLayer and the CGContext may of different size, and I don't want any scaling.

Thanks!
Draw part of the content of a CGLayer
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I have CGLayerRef which is updated periodically, I also have a CGRect indicates which part of the CGLayer got updated.  Is there any way I can draw only the updated area of the CGLayer to the targeted CGContext.  The CGLayer and the CGContext may of different size, and I don't want any scaling.

Thanks!