I want to imitate Photoshop layer 'soft light' blending in iOS

Question

In Photoshop a layer can be blended with a layer below it using many different ways, ie Normal, Dissolve, Darken, Soft Light, etc. I would like to duplicate this effect programmatically in iOS using the core graphics api. Any ideas?

Answer 1

You can't apply different blending modes between CALayers (at least, on iOS), but if you're implementing -drawRect: or otherwise creating an image, you can certainly use soft light blending with the kCGBlendModeSoftLight CoreGraphics blend mode.

Answer 2

There is an example of layer blending in iOS using Core Graphics in the project I just posted here: https://github.com/esilverberg/ios-image-filters

I only implemented overlay blending so far.