Hi I am trying to bake lightmaps in blender and then use them in babylon app. As it turns out it’s not that straightforward. I am using PBR materials and I specifically want to have separate albedo and lightmap image on the objects. I have already read this thread on the topic but I still feel lik…

Hey @sebavan @Evgeni_Popov . You mind explaining lightmaps a bit further?

The easiest way to do this is to bake in blender with cycles. Then paste the map to the self-luminous channel and specify the uv. No code is needed, but it will break the glow. Later in the code you can move it to the lightmap channel to eliminate the effect on the glow.

That’s almost exactly my flow currently. The problem is not how to get lightmap from Blender to Babylon but rather what should be the format of that lightmap coming out from Blender. Right now I can see that Babylon is using proprietary RGBD format which Blender does not generate. I even tried repro…

I actually don’t think it’s a good idea to use RGBD. Because currently the lightmap channel in babylonjs does nothing more than superimpose the lightmap colors onto the final output color. [image]

But he doesn’t give a comparison, and in reality the RGBD improvement may not be that great. Later he himself complains about overexposure of the environment [image] RGBD Lightmap banding Questions Mmmm, I’ve repeteaded the same code as yesterday and now the PNG, as you …

I agree. In my opinion, the topic is still open. I think it’s worth following (I do) but I wouldn’t dare using it in a productivity environment with a strong requisit about colors/exposure. At least, not just yet. Of course, my opinion only.

But that’s not a problem, because the difference between RGBD is simply the use of the A channel to increase the color range. The existing process remains exactly the same, except for a single sentence texture.isRGBD = true. Even if you paste the rgbd texture to the self-luminous channel, it shoul…

Okay. What is proper way of exporting blender lightmaps which when pasted in babylon will give me exactly the same results as usual Blender render? RGBD is simply the use of the A channel to increase the color range. It’s not “simply”, this is the only proper way to have results that look exactl…

You can basically convert .hdr to RGBD format, which is essentially an image with a transparent channel. I’m not sure how the native blender baked mapping outputs hdr. Some baking plugins export in hdr by default or support setting rgbd encoding. A .rgbd map generally looks just like a normal png…

Proper lightmap workflow and formats

Questions

zylkowski June 12, 2023, 10:46am 6

That sounds like lightmaps are just broken then? I can see some good looking results with using RGBD though here

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Proper lightmap workflow and formats

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