[Request]:Negative Lights

Would it possible for the lights to have negative values and actually subtract light from the scene?

I know that’s not the most realistic approach to lighting, but often would help to tweak the scene faster, or even save on the amount of lights needed to lit a scene (you may not have to use too many smaller lights just to leave some part of the scene darker).

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Hi Tomas,

You can create “Negative Lights” by creating a blueprint with a light component. Then in the construction script, you can get your light and then set the brightness to a negative from there. I have included an image example. Please let me know if there is anything else I can assist you with.

Thank you,

Alexander

brightness.png

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Oh, that’s great. Didn’t thought that if light is not able to go below 0 in the brightness property that it would be supported by the renderer.

This works great. Thanks.

Is there any reason why not to allow lights go below 0 by default?

Negative light rendering has been reported to cause “visual errors”, so it was not encouraged, but possible if necessary. Also, we have been focusing the engine’s development on realism.

So far seems to work ok here. It helps a lot to push the Min Roughness to 1.0, to get more of what would be expected from a negative light.
I understand the push on more realism and physically based rendering. Will make a feedback on that soon :slight_smile: