Lightmap Bake not updating baked PNG's

[dre4mer]

Hi Guys,

I'm not sure if i'm not understanding how the lightmap bakes are supposed to work, but if I bake to geo, then move the light and bake again the image stays the same on the geo. This is true if I change the name for the bake prefix as well so the PNG is for sure an updated name.

It updates the mtl in the surface shader name, and the PNG name. But the contents of that PNG remains the same.

I've messed with trying to reassign a new lambert/surface shader to get around this, but it seems to "break" the geo and then all bakes are mostly black unless I start over with a fresh plane again. At which point it will bake fresh and correctly. But only the first bake, till I move the lights again.

Any insight would be most helpful!

maya 2017 update 5 and latest of vray next

[dre4mer]

I guess researching it a bit more perhaps this is the way it fundamentally has to work, by definition lightmap baking in this manner has to remove the original material and place it's own on. So the only way to update the lighting on the object would be to reassign the original material, and then re-bake. I don't quite know how this is very usable though as I have a scene with thousands of objects and materials, re-linking them constantly to make every change to any object would be time prohibitive. It's like I would need a quick script that a button press would revert the object back to it's original state so that I could rebake the new lighting position. But I haven't found something like that yet.

Assuming this is all correct is there any other ways to go about this that would make it more flexible? I'm attempting to bake lighting for a VR experience in unity.