Holy Shit!

Doom · Post by **Doom** » Mon Oct 06, 2003 3:14 pm

He can run Zdoom smoothly even using the highest resolutions, though the last one isn't that fast. But as for testing purposes, I tried the 800x600 which's just the greatest res my PC will handle without going laggy.

No extra setup but controls and mouse were modified, also a key bind for the FOV feature and basically, nothing that might affect game's performance for the good in any way.

His pc runs with 8mb RAM more than mine, but I doubt it would make any difference.

However, I'm telling you this cos it's true, I've tested it heaps, I wouldn't have reason for saying "it runs faster with a g-force" if it didn't, makes no sense and nope, it's Zdoom what I ran, not Zdoomgl or anything related to OpenGL.

Does anyone have a video accelerator plugged to a PC about as fast as mine?, go try it and tell me if it lags when you walk near to wall impacted with several rockets and tell me if I'm wrong.

Biff · Post by **Biff** » Mon Oct 06, 2003 3:39 pm

I have a GeForce2 card in 1 Ghz P3. If I plaster lots of decals around and walk near, it really bogs the machine down. More noticable at 1024x768 than 800x600.

Another thing that might account for performance differences is the video card port...ISA being the worst, PCI better, then the AGP.

Just tested this machine (at work), 2.3 Ghz P4 Dell. In the highest video resolution, it lags quite a bit when I walk near a wall where I shot some rockets to leave decals.

bimshwel · Post by **bimshwel** » Mon Oct 06, 2003 3:41 pm

The moral of this story: Stop shooting the walls.

HotWax · Post by **HotWax** » Mon Oct 06, 2003 4:05 pm

Doom wrote:Does anyone have a video accelerator plugged to a PC about as fast as mine?, go try it and tell me if it lags when you walk near to wall impacted with several rockets and tell me if I'm wrong.

I have a 1.67GHz with 512MB RAM and a GF4 4600 with 128MB of VRAM, so by your standards I should be at warp speed at all times.

Once the decals start piling up, even my computer slows down... something that certainly wouldn't happen if the 3D acceleration in my card was being utilized...

If you have a sufficiently shitty video card that the actual data is being bottlenecked on its way from system RAM to your monitor, than I could see that being a problem. Any decent system these days (read: not ancient) should have an AGP card of some type in it. I'd imagine a Riva TNT-based card would run for about $5 nowadays...

In the meantime, I'd suggest turning decals off.

Ultraviolet · Post by **Ultraviolet** » Mon Oct 06, 2003 11:43 pm

For software-only renderers, high-end video cards are only needed in order to run in much higher resolutions. No matter how many effects are showing on screen, the number of pixels showing on the screen is the only thing that matters to your video card.

Doom -- regarding your comparison of performance on different machines:
Processor speed isn't the only relevant thing in that situation. Consider the bus speeds, memory speed, memory timing, amount of memory, little tweaks to the BIOS, messing with things like the AGP aperture size, how much RAM is available to the program, operating system settings (like having fading menus and all the effects in XP turned on)... I highly doubt that you made sure your test systems were identical in every department but video card and processor before you did your little half-assed test.

Hirogen2 · Post by **Hirogen2** » Tue Oct 07, 2003 5:32 am

How about this: the decals (partially alpha-blended) pile up, which is calculated by the engine. AFAIK only the video access part (i.e. making walls actually appear after they have been calculated) is done by DirectX and/or similar.
Heh I wonder that P:AR E1M6 runs with 29fps on 640x400 in some places

(AXP2K+ 1.667GHz GF2MX400/32MB, 256MB RAM)

HotWax · Post by **HotWax** » Tue Oct 07, 2003 8:21 pm

Hirogen2 wrote:How about this: the decals (partially alpha-blended) pile up, which is calculated by the engine. AFAIK only the video access part (i.e. making walls actually appear after they have been calculated) is done by DirectX and/or similar.
Heh I wonder that P:AR E1M6 runs with 29fps on 640x400 in some places (AXP2K+ 1.667GHz GF2MX400/32MB, 256MB RAM)

No, if D3D was required to render ANYTHING, than it wouldn't run on a computer without a D3D-capable card. It does. All the video card does is take EXACTLY WHAT IT'S GIVEN and put it on the screen. The CPU reads the texture, applies the decals to the texture, calculates the appearance of the wall in 3D space, converts it to the 2D screen, applies other post-processing effects, and generates a bitmap image of what the final screen will look like. It then sends that bitmap to the video card, which DOING NOTHING TO THE IMAGE, sticks it on the monitor. No part of its acceleration is used to draw the image.

To contrast this, when Quake 3 wants to render something, it sends the 3D location of each vertex to the video card, the lines that will be created between those vertexes, the surfaces that are made up of those lines, the textures that will appear on those surfaces, transformation effects that will apply to those surfaces and textures, and other parameters such as light color, fog, location of point lights in space, etc etc etc. All of this information is sent to the video card, a viewpoint is specified, and the card itself uses the information to render a 3D world. This method is VASTLY different from the way Doom renders everything in software.

Post by **randi** » Wed Oct 08, 2003 4:02 pm

A while ago, I did try using the video card's blitter to copy the screen from main memory to video memory, and it worked great. The screen copy time was cut in half. Then it stopped working for some unknown reason, and I haven't been able to get it to work since. So theoretically, the video card should be able to accelerate software ZDoom.

Doom · Post by **Doom** » Thu Oct 09, 2003 6:31 am

That could somehow explain why my friend can run Zdoom faster having a slower CPU.

Biff · Post by **Biff** » Thu Oct 09, 2003 7:56 am

This is set by default in current versions of zdoom:
vid_noblitter=true

I think Randy has left the "blitter" code in zdoom, so if this is set to false it might work for some reason on a particular machine...