OMWGame vs ESM

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Ravenwing
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OMWGame vs ESM

Post by Ravenwing » 02 Nov 2018, 05:34

So I'm planning a new page for documentation that involves an intro to modding in general and how plugins and files overwrite each other. Defining the different file types, at least at a basic level will be important. As I was thinking about it, I realized I've been thinking of *.omwgame as equivalent to *.esm. Is that actually true though. I fully understand what an ESP does, but what exactly is special about ESMs? And is that distinction different than OMWAddon vs OMWGame? Also importantly, is OpenMW's handling of ESMs different than Morrowind's?

From what I understand ESMs are loaded first in vanilla, and an ESP that requires an ESM won't play without it. But there can be multiple ESMs, and it seems illogical for it to be possible for there to be multiple OMWGames.

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AnyOldName3
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Re: OMWGame vs ESM

Post by AnyOldName3 » 02 Nov 2018, 13:00

(At least with the later games - I'm not sure how much this applies to Morrowind) The original CS won't let you make an ESP which depends on another ESP, but if you use another tool to make or edit the ESP, that will let you make an ESP that depends on another ESP, and then the engine will do what you've told it.

My guess is that we've decided this non-distinction is silly, so have made our CS let you make an omwaddon that depends on another omwaddon, in which case, you'd onkly ever need one omwgame.
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Chris
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Re: OMWGame vs ESM

Post by Chris » 02 Nov 2018, 18:03

Ravenwing wrote:
02 Nov 2018, 05:34
As I was thinking about it, I realized I've been thinking of *.omwgame as equivalent to *.esm. Is that actually true though.
Not really. An omwgame is basically like an esm that has no masters. In the vanilla engine, there's little difference between an esm with masters and an esp with masters, and this is what omwaddons are. AFAIK, the only difference with the vanilla engine is that esms are always loaded first before esps, and with the vanilla CS an esp can only depend on esms, however these distinctions and restrictions are pretty silly. You need to ensure your load order is correct anyway, so there's no functional difference.

In the vanilla engine, there's also little difference between an esm with masters and an esm without masters. However, with OpenMW it can be beneficial to know what "game" is being played (to select between different mod lists or character profiles), so it uses the lack of masters to determine whether something is a base game file or not, and this is what an omwgame is.

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Ravenwing
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Re: OMWGame vs ESM

Post by Ravenwing » 02 Nov 2018, 20:28

Thanks guys! This clears it up I think. The distinction does seem pretty unnecessary as it's all just records overwriting other records.
Chris wrote:
02 Nov 2018, 18:03
You need to ensure your load order is correct anyway, so there's no functional difference.
So I'm correct in assuming that OpenMW doesn't maintain the "ESMs always load first" behavior?

This should be enough to get me started, but if anyone else has something to add, feel free!

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MinerMan60101
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Re: OMWGame vs ESM

Post by MinerMan60101 » 03 Nov 2018, 04:43

More than you ever wanted to know about esm/esp files:
https://www.tamrielrebuilt.org/content/ ... ugin-files
Interior and Exterior Developer | PT, TR

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Ravenwing
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Re: OMWGame vs ESM

Post by Ravenwing » 03 Nov 2018, 16:44

This is great! And so much other info as well. I'll be sure to check here for modding questions in future to see what's what. Thanks MinerMan60101!

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