Creating a Glass Color Filter for light

Development Rendering
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Hello everyone,

I’m currently struggling with creating a material that can function as a color filter. My goal is to produce a transparent material that alters the color of incoming light based on the material’s designated color. For instance, if white light falls on the filter and the filter is red, the light that passes through will be red. The green and blue values of the light will be filtered out.

I would like to emphasize that I only want the remaining light to change color. Simply adjusting the emissivity or color of a glass material does not meet my requirements. My desired result is that when I shine the filtered light onto a white wall, only the filtered color is visible on the wall. Essentially, I want to create a window like the ones you see in colorful churches, as shown in the attached image.

Any assistance or guidance in achieving this result would be greatly appreciated. Thank you!
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Currently this can only be accomplished with static (baked) lighting, or by faking it. I believe there are plans to add colored translucent shadows to lumen in the future.

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There are plans for UE5 translucent shadows, it’s considered a strata development, and I don’t understand the technology well enough to guess whether it’s a near turn development, or if you’ll have to wait a while.

Baked lighting can do colored shadows, GPU lightmass is even pretty quick about it all things considered. There are ways of faking it, and my gut tells me that you could try a rect light with a source texture matching your albedo.

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