Applying a CIFilter to a CALayer

Question

CI Filters are now available in iOS 5, and I\'m trying to apply one to a CALayer, the way you\'d do it on Mac. Here\'s my code:

CALayer *myCircle = [CALayer         


        

Answer 1

Aside from the fact that CIDiskBlur is not available (as of iOS SDK 5.1) and that setFilters: seems to be not available either you could do the following:

Create the input CIImage from the contents of your layer:

CIImage *inputImage = [CIImage imageWithCGImage:(CGImageRef)(myCircle.contents)];`

Apply your filters and get the result in an CGImageRef:

CIFilter *filter = [CIFilter filterWith...];// A filter that is available in iOS or a custom one :)
...
CIImage *outputImage = [filter outputImage];
CIContext *context = [CIContext contextWithOptions:nil];
CGImageRef cgimg = [context createCGImage:outputImage fromRect:[outputImage extent]];

Finally set the CGImageRef to the layer:

[myCircle setContents:(id)cgimg];

This should work :)