Local Transparency

node

Inputs:

Source, The image that will be affected.
Reference, The luminance of the Reference image will control the opacity of the Source.
The Source will be made transparent where the Reference is light, and opaque where the Reference is dark.

Parameters:

Intensity, Controls the overall strength of the effect.
A value of 50 will produce a result halfway between the Source image and the full effect.

Usage Example:

We can use a checker pattern to control the opacity of a circle

circle checker

This is how the two levels are connected in the FX Schematic; by connecting the checker level to the Reference input, we will use its luminance to mask portions of the circle

graph

Here is the result; the red circle is visible within the black areas of the checker pattern and not in the white areas

example example_2