Question

I have a view with a CATiledLayer backing. I want to take the visible tiles from this CATiledLayer UIView and add it to another view as its CALayer backing, thus recreating the visible image in another UIView that doesnt use CATiledLayer.

The reason I want to do this is I will use this second UIView to mask the effect of updating the CATiledLayer backed UIView – this currently produces a flicker as all tiles are re-loaded.

The problem is, I’m not totally sure how i would do this. Any ideas?

Answer 1

CATiledLayer is a subclass of CALayer providing a way to
asynchronously provide tiles of the layer’s content, potentially
cached at multiple levels of detail.

You can render the visible things in the layer into a CGContextRef with:

- (void)renderInContext:(CGContextRef)ctx

And then use this to update your other layer by settings its delegate and implementing the

- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)context 

ss shown here http://www.raywenderlich.com/2502/introduction-to-calayers-tutorial

But honestly I don’t think this is efficient.