Performance drops in cities

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Mantar
Posts: 38
Joined: 17 Jul 2020, 23:32

Re: Performance drops in cities

Post by Mantar »

nowheredan27 wrote: 17 Feb 2021, 02:31 EDIT - OK so basically I copied some stuff from this Glow in the Dahrk mod that I don't use and that's what caused the textures to go missing.
Is there a way for me to download the vanilla version of just these textures again? I really don't wanna have to reinstall the game just for this :cry:
If it's only replacing the texture, you can simply delete the offending texture from your data folder and the game will revert to the default one in the game files. If there's a model involved this may not work, but I don't think that's the case with Glow in the Dahrk.
PopeRigby
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Joined: 14 Jun 2019, 21:42
Gitlab profile: https://gitlab.com/PopeRigby

Re: Performance drops in cities

Post by PopeRigby »

Good point. Is there a build flag to disable debugging, or should I leave it on just in case I need to report something?
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AnyOldName3
Posts: 2668
Joined: 26 Nov 2015, 03:25

Re: Performance drops in cities

Post by AnyOldName3 »

We have different configurations, namely Release, RelWithDebInfo and Debug. Release has all optimisations turned on (although LTO is optional) and RelWithDebInfo has *nearly* all turned on, but some are left off as they change the code so much that it's not practically debuggable without helping speed much. RelWithDebInfo and Debug have debug information, which is embedded into the executable on Unix-like OSes, so might make your instruction cache miss more often, but comes in separate files for Windows, so you only have a hit from the missing optimisations there. Depending on your build system, you either tell CMake which configuration you want at configure time, or tell your build system at build time.
tekhneeton
Posts: 3
Joined: 09 Dec 2020, 16:00

Re: Performance drops in cities

Post by tekhneeton »

Looking at your settings I must ask: Antyaliasing x8 ? Seriously? In the Windows-land I haven't seen a game allowing that since over a decade, when it was a heyday of DirectX 9.0c . And today most games I play don't allow anything MSAA x4. And sometimes not even that, with FXAA being only option. And for a good reason I say. There is hardly any visual difference on modern displays with their high DPI/small pixel size (compared to what we had decade ago) and computation cost can be abhorrent.

I have very similar specs to yours (also r7 3700x, 16 gb RAM, but RX 5700 and 2K display), I set AA to x2 and all things considered I am quite happy with how OpenMW looks and runs. Actually in all games I play I set AA to x2 I think.

So if you crave for higher FPS I would suggest you first tune down this crazy AAx8 to x4 or even x2 and see how it affects your framerate and visuals.
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AnyOldName3
Posts: 2668
Joined: 26 Nov 2015, 03:25

Re: Performance drops in cities

Post by AnyOldName3 »

Around 2010 or so, things switched from forward rendering to deferred rendering, which made it much cheaper to have lots of lights, but initially made MSAA impossible, and when workarounds had been devised, still made it very expensive. For several reasons, OpenMW uses forward rendering, and is likely to keep doing so in the future, so MSAA is relatively cheap, and doesn't get hugely more expensive at higher values. We also don't have a post-processing shader system, so can't add any post-process AA like FXAA or SMAA. Also, post-process AA is generally pretty bad. FXAA struggles to help as much as 2x MSAA does without making everything blurry as it's just a selective gaussian blur, so either doesn't blur enough of what you want blurring or mistakenly blurs things you didn't want. SMAA is much better than that, but still can't compete with high values of MSAA.

Having a high-resolution monitor means not having much AA looks less bad, but unless you're on a 23" or smaller UHD monitor, things will look visibly better with more MSAA, and in OpenMW, it shouldn't be much more expensive.
PopeRigby
Posts: 16
Joined: 14 Jun 2019, 21:42
Gitlab profile: https://gitlab.com/PopeRigby

Re: Performance drops in cities

Post by PopeRigby »

I'll try experimenting with turning it down anyway.
PopeRigby
Posts: 16
Joined: 14 Jun 2019, 21:42
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Re: Performance drops in cities

Post by PopeRigby »

psi29a wrote: 17 Feb 2021, 10:58 Might be worth mentioning... these are developer builds, not release builds. Meaning we've packed them full of debug information which might have an impact on performance.
How can I disable them? Or should I leave them on in case I need to report a bug?

EDIT BY ANYOLDNAME3: Added a ]
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