Older bump mapped mods (and how to make them work in OpenMW)

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Capostrophic
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by Capostrophic » 05 Oct 2018, 12:46

Ouch. I don't want NDL and Bethesda lawyer squads knocking on my or anyone else's door. :P ( :oops: )

As far as I can tell, it's not the source code - that evaluation copy doesn't include any - so none of us know how the thing should actually be implemented, we only have the idea of what should be implemented that can't be patented. It's physically impossible to take more copyrighted material than necessary for implementing EMBM considering there isn't any and the docs were used for educational purposes. Theoretically this should fall under fair use.
Hmph.
:?

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Capostrophic
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by Capostrophic » 05 Nov 2018, 18:43

I guess I should say something.

Morrowind doesn't support using environment maps on skinned objects (other than the enchanted equipment environment maps, I guess), so bumpmapping doesn't work on skinned models. But that shouldn't be replicated I suppose. MCP fixes that.
Gloss map support in Morrowind is broken for whatever reason. MCP fixes the removal of gloss map references in the meshes by Morrowind and re-enables it, but instead of using the alpha channel of bump maps, which would be logical, the blue channel is used for the gloss map. Not sure if Morrowind simply behaves as if the blue channel is white or handles the bumpmap as a monochrome texture.

1Mac
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by 1Mac » 25 Feb 2019, 23:50

A question about renaming MCP fake bump maps for OpenMW compatibility. I've run into many such maps with lots of black, which I've never seen in proper normal maps before. Here's an example from Hirez Armor Native Styles.

https://drive.google.com/file/d/12qYzBQ ... sp=sharing

What would happen if I renamed these files with a _n suffix to use them as normal in OpenMW? Less-than-ideal, or totally awful?

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Capostrophic
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by Capostrophic » 25 Feb 2019, 23:55

The lighting will look very wrong.

MCP enables the usage of the blue channel as the gloss map channel, which (technically) differs from Gamebryo/NetImmerse specification of gloss maps -- they're supposed to be in the alpha channel of the bump map. This probably was the only way around? Anyway, the gloss map will control the level of environment map reflectivity in the specific texel.

Once Morrowind-like bumpmapping is implemented somehow, making MCP behavior optional shouldn't be extremely difficult.

1Mac
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by 1Mac » 26 Feb 2019, 00:41

Hmm, that makes them sound more like hacky speculars than hacky normals. Could you convert them to grayscale and change the suffix to _spec and have decent results?

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Capostrophic
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by Capostrophic » 26 Feb 2019, 13:45

You probably would be able to utilize it as a specular power channel in the specular map. But I'd rather not count on that.

Red and green channels are still a part of a proper heightmap. Heightmaps can't be utilized for either normal maps or specular maps, but they can be used for parallax. YMMV.

I still want to make OpenMW itself compatible with Morrowind bump maps.

1Mac
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by 1Mac » 26 Feb 2019, 21:26

That would certainly be easier than trying to shoehorn those maps into something for which they weren’t designed.

I have another question for Lysol or whomever can answer. Lysol recommends deleting blocks for environmental maps when converting meshes for use with actual normal maps, presumably because that’s how fake bump maps are applied. But some mods have actual environment maps assigned to these blocks. I’m about 90% certain that these needn’t be deleted in these cases, but I wanted to check.

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Capostrophic
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by Capostrophic » 26 Feb 2019, 21:38

Nah, in cases the environment map is added intentionally you usually shouldn't get rid of it. For example, in Pherim's Real Reflective Weapons - Iron.

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lysol
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by lysol » 26 Feb 2019, 21:40

Capostrophic actually knows more about this than I do, but you are correct. I know of at least one mod that makes shiny weapons with this method. In this case you should of course not edit anything in the nif file, since the shinyness is something you actually want.

EDIT: Haha. Well, I told you he knew more.
Normal mapped texture replacers, exclusive for OpenMW:
My Nexus page

1Mac
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by 1Mac » 27 Feb 2019, 19:51

Thanks for the answers, guys. It seems like this is something that should be clarified in the guide, lest people delete NiTextureEffect blocks indiscriminately.

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