My base image is a complex shape with multiple colors and an alpha background.
My shimmer effect is a white slanted gradient with an alpha background.
My goal is to animate the shimmer image over top of the base image, but make the alpha values of of the shimmer match those of the base image.
I’ve only used layer masks to hide areas based on the color, not to both show AND hide parts of an image. Will I need to create multiple masks to achieve this? A white version of my base image that will show through the masked shimmer image, all on top of my colored base image?
Since your shimmer effect is created by moving a single image/layer over a base image, you only need one mask in the shape of the non-alpha values in your base image. You will likely need to use a container view for your shimmer image view/layer that you overlay onto of the base image, then set the image mask on the container.