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Named mask creation for external lightmap tweaking

Any chance of outputting named masks for the objects? Would be handy for editing the brightness of overly bright exterior objects in post.

You mean something like a color ID/Material ID like in Corona or Vray?

yeah, like a cryptomatte.

The only reason I ask is that I have a scene with both interior and exterior, I’d prefer to keep indoor lighting provided mostly by the outdoor natural light, as it renders faster and looks nicer. So I opened up the lightmaps with the hopes of reducing the brightness of the outdoor stuff, but couldnt find the correct areas on the lightmap to darken.

maybe if masks could be created based on the groups of the imported fbx. For example in the 3d application the scene is created in, you could create an outdoor group containing exterior models and an indoor group containing interior models. Then the baking process could create a mask for the indoor and a mask for the outdoor. The two masks could then be used in post to alter the exposure of all the objects which are in the outdoor group.

You could even create groups for each room, and then use the resulting masks to for control over exposure of rooms individually.

In Unreal you can create a volume with additional settings, like brightness or contrast to solve this. I don’t know if this is possible in Shapespark. Would be useful because we often have to deal with combined scenes.

Yeah, I wonder if that option has been omitted to keep it as computationally light as possible for web.

Maybe we need to ask the developers of Shapespark?

We are going to experiment with some ways to amplify exterior lighting when it enters the interiors, so that exteriors and interiors would effectively use different light strengths. This should help in producing well-lit mixed exterior-interior scenes. Some potential approaches has been discussed in this thread: No collisions in VR.

We’ll do some preliminary tests in October, and then we’ll have some estimate on when such a feature could be added.



I have an (untested) idea how it might be possible to produce something like a mask of the outdoor surfaces using the current capabilties. If you temporarily modify materials not to let the exterior light enter the interiors, and turn off all the interior lights, then baked lightmaps should be non-black for the outdoor areas and black for the rest. By modifying materials I mean making windows, doors etc. fully opaque.

For this “outdoor mask” bake you could use low number of samples and bounces. You might also need to turn off post-processing (disable “Enable filters” in the “Bake” tab) to prevent dark interior pixels from being flooded.

That’s a great idea! Thanks Wojtek.