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

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AnyOldName3
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by AnyOldName3 » 25 Sep 2018, 19:45

Is that a description of the vanilla behaviour or the MGE XE behaviour? I know there's supposed to be something hacky about how MGE XE actually uses the normal maps in the environment map slot, and that definitely doesn't sound like bog-standard normal mapping.
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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 Sep 2018, 19:49

Pure vanilla behavior. MCP option applies the local lighting to the environment map colors, but that's it. MGE XE doesn't change anything about bumpmapping - PBR alpha uses normal mapping functionality of PBR but that's separate from bumpmapping - and EMBM is not something unique to Morrowind, just obscure as a technique.

Edit: currently environment maps are applied *after* the lighting is, but the order can be swapped so it's not impossible to set up the MCP behavior of environment mapping.

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AnyOldName3
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by AnyOldName3 » 25 Sep 2018, 21:06

There shouldn't be any question about implementing pure vanilla behaviour, so I think we should go ahead with it whenever someone's ready.
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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 Sep 2018, 13:54

I found out that openmw handles spherical environment maps differently, but I'm not sure in what way yet. This is a blocker.

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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 » 03 Oct 2018, 16:29

I've got some new information and links to additional sources of helpful info. Will report back soon.

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AnyOldName3
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by AnyOldName3 » 04 Oct 2018, 18:36

Note: this is actually a full Gamebryo copy, so its licensing is questionable.
I'm not sure how much this applies if you're only looking at documentation instead of the source, but bear in mind we're supposed to clean-room reverse engineer Morrowind in order for Bethesda to have no grounds to shut us down. If that does apply to documentation, then you might have removed your right to implement the same system in OpenMW. Zini etc. should definitely be consulted before proceeding.
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wareya
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by wareya » 04 Oct 2018, 20:49

I'm pretty sure it's valid as long as the person reading the documentation and doing the programming (on that particular task) are different people, at least in the US. In fact, in the US I'm pretty sure that method even applies to code. And european countries tend to have more liberal reverse engineering laws than the US.
paying attention to #1751 #2473 #3609 #3862/#3929 #3807 #4297 #4623

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AnyOldName3
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by AnyOldName3 » 04 Oct 2018, 21:46

But Capostrophic is the one who's read the documentation and he's also the one who I thought was going to write the implementation. Now I've read the quoted excerpt, if the rule applies, I wouldn't be allowed to implement it either, so we're basically stuck with just Drummyfish who's done shaders before and hasn't read it.

Basically, we need someone to confirm whether the rule applies to potentially dodgily-sourced documentation. I think it might do, as I remember Dolphin's developers got a little bit panicked when the programmer's manual for the Wii CPU got uploaded to their forums.
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psi29a
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Re: Older bump mapped mods (and how to make them work in OpenMW)

Post by psi29a » 05 Oct 2018, 09:21

Having knowledge to do a thing, under a particular license, does not prevent you from writing your own implementation. Otherwise every knowledge-worker (aka software developer) couldn't do their job when they move to a new company.

My company for example forbids me from providing to coworkers information about how I solved a problem at a previous company. That does not mean I can't use what I've learned to create something new based on the knowledge I have gained.

The same legal question is applied to plagiarism. You copying word-for-word? You're up shit creek and a shitty person for not using your own words.

Reverse engineering for the sake of interoperability is actually a well defendable position and has been used in courts. Although not exactly the same thing, the Oracle vs. Google case (aka are headers licensable?) is providing the point that being able to communicate with software is 'open' and not copyrightable/patentable/licensable. This would also invalidate the AGPL license as well as a result. I digress...

Knowing how something is done, regardless of method, does not constitute IP theft if you can write an 'original' replacement. Think about the when JohnC wanted to open-source Quake3 but couldn't because there was a copyrighted (or patentended?) function, he had to re-write a function that turned out to be better, to replace it and then GPLed it.

Another example is the S3TC drop-in replacements. We all know how S3TC works, we have the code examples, but we couldn't implement without a license. So people made their own 'compatible' versions like S2TC to be a drop-in replacement which was legal.

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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 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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