what's the lowest system gzdoom would run on?

[invictius]

Posting here because Maes and co. will see. Just say you has a really good opengl2/3 card such as a geforece 7950 (most powerful agp iirc), but a crappy p2/3 cpu... since a whole load is taken off the cpu for rendering, could you get away with it? Just saw the monochrome mapping project for example, doesn't seem like the map would strain a system much even in software, if it were made for that.

[Blzut3]

invictius said:

geforece 7950 (most powerful agp iirc),

Most powerful AGP card is a Radeon HD3850 or HD4670 (similar in power, and the HD3850 has hardware double precision floating point for the 2 people that care about that on a legacy system). These are OpenGL 3.3 capable cards although the final driver for them is unfortunately notoriously buggy (for developers at least). The Geforce cards are only OpenGL 2.1.

invictius said:

but a crappy p2/3 cpu... since a whole load is taken off the cpu for rendering, could you get away with it?

GZDoom is currently compiled for SSE2 CPUs (P4/Athlon 64 or later) so not out of the box. In theory you could probably compile GZDoom with MinGW and run it on one of these systems.

Now the answer to "could you get away with it" really depends on a lot of factors including your exact definition of that.

[Graf Zahl]

Blzut3 said:

GZDoom is currently compiled for SSE2 CPUs (P4/Athlon 64 or later) so not out of the box. In theory you could probably compile GZDoom with MinGW and run it on one of these systems.

Not correct for the official 32 bit build which uses x87 instructions and the XP compatibility toolset. On such an old and slow system you'll run into problems on a medium sized Boom map already. I still have my 2004 computer, it got a Geforce 6800 and a P4 CPU with 3.1 GHz. On that system a map like P:AR'S M6 opening cave scene runs with less than 40 fps at 1024x768, with lower resolution it gets a bit better. Dynamic lights are out, though. Those will drop frame rate to the low 20's.

Considering that the CPUs you propose are even slower than this I do not see much coming out of it. It will run vanilla maps but beyond that it'll get hairy.

I still remember when I played P:AR with that renderer for the first time, which was on my computer previous to that, this map was close to unplayable. And if you use AMD graphics hardware there's another problem that will make things worse: Driver overhead for AMD is magnitudes higher than for NVidia, it has been like that since the first time I ran some comparative tests and nothing has changed about it. On a slow CPU that's the kiss of death.

[invictius]

Graf Zahl said:

On that system a map like P:AR'S M6 opening cave scene

E1M6?

[Graf Zahl]

What else? Of course E1M6.

[Blzut3]

Graf Zahl said:

Not correct for the official 32 bit build which uses x87 instructions and the XP compatibility toolset.

Thanks for the correction. I missed the commit where you added that to the CMakeLists.txt, so I thought we used the default. (I will note though that MSVC will still generate x87 instructions at times with the SSE2 arch, so "uses x87 instructions" doesn't say anything about the setting of /arch.)