dhewm3
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dhewm
Low framerate on old pc compared to original game
I've got laptop for retro games. With no special reason I've decided to try dhewm3 on it. Laptop is based on core duo t2600 (it's a 32bit cpu) and ati x1900. I'm sitting on windows xp. Since latest version of dhewm3 doesn't work on XP I'm using on 1.4.0.
So, high settings, 1024x768 and "eax" off, original doom 3 1.3.1 - ~50fps and dhewm3 - ~35fps.
No special request, just interested in reason why source-port is slower? Thanks.
No idea. You could compare the configs to see if both use the same settings, maybe one uses texture compression and the other doesn't or something like that?
i did my best comparing configs and even transfered one to another, no chance 30-35 in source port and 50 in original.
original config have these lines while source port doesn't have such:
seta r_cgFragmentProfile "best" seta r_cgVertexProfile "best"
dhewm3 removed some old render paths, now it always uses what used to be the "best" profiles, so I think this shouldn't be it.
What happens if you rename dhewm3.exe to Doom3.exe ? It's possible that the GPU driver does some optimizations based on the executable name
Here's the latest dhewm3 code built for WinXP, with Visual C++ 2013 (you might need to install the corresponding C++ runtime if you don't have it already): dhewm3-1.5.2pre-winxp.zip (I haven't tested it, I hope it works)
Sadly, it doesn't work. Renaming dhewm3 also changed nothing. I even took a screenshot from original and dhewm3 and they are visually identical, just one shows 50 fps and another one 30-35.
No idea then :-/ Sorry that the new build doesn't work, but as I don't have a PC with WinXP I can't debug that issue.
dhewm3 supports only OpenAL sound, it's possible that this has more overhead than the old sound system (or maybe you have a Soundblaster Audigy or XFi with hardware acceleration for sound effects that OpenAL Soft does it in hardware). Maybe OpenAL Soft settings can be tweaked to get better performance (for worse audio quality), see https://github.com/kcat/openal-soft/blob/master/alsoftrc.sample or maybe you could even get the old creative openal32.dll to work (if you have such a soundcard)
UPDATE: Another idea, Doom3 GPL had "Carmacks Reverse" for shadows removed because of patent issues, since 1.5.1 dhewm3 supports that again (the patent has expired). It didn't make any difference on any hardware I tried (including slow Intel integrated GPUs and Raspberry Pi 4), but maybe for your card/driver it does make a difference. Which would bring you back to figuring out why the new build doesn't work on WinXP..
dhewm3 removed some old render paths, now it always uses what used to be the "best" profiles, so I think this shouldn't be it.
What happens if you rename dhewm3.exe to Doom3.exe ? It's possible that the GPU driver does some optimizations based on the executable name
This must be why i saw doom3 run on omap3 + powervr but It can't run right on omap4. Can you tell me which commits removed these? Thanks
