The output quality of the XVR-4000 vs that of the V12


Well-known member
Dec 16, 2019
South Africa
Quake III is in no way optimised to run on this hardware, hence the low frame rate, and the colour palates also seem to differ quite substantially, in that the XVR-4000's is far more bland!

The XVR-4000 employs full screen antialiasing, whereas the V12 offers no antialiasing. (As you will see in this post, there are pros and conns to this, depending on what filter you're using!)

The output quality of the XVR-4000 in Quake3 (Max settings)

The output quality of the V12 in Quake3 (Max settings)

The textures on the V12 do appear to be sharper, as there's no antialiasing being applied to them, so there are pro's and cons to full screen antialiasing.

There are lots of jaggies in the V12's rendering in comparison.

There are also artefacts present around the lava in the V12's rendering that aren't present in the XVR-4000's rendering.

Here's a combined picture:

I have managed to sharpen up the textures rendered by the XVR-4000, by applying a catmall filter. (the right-hand side of this image shows the catmull filter in effect)

These are the filter options available for the XVR-4000 and I think that I was originally using the Mitchell filter.

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Active member
Jun 23, 2019
These comparisons are very interesting, I'd be doing the same thing if I had different examples of old OpenGL Unix hardware. Since having some experience with the SGI madigras hardware and then v12 afterwards I also noticed some of the rendering peculiarities the v12 has, notably the texture blending issues like that lava on the floor and also the sky rendering issues. I think the v12 has some driver issues that never got fixed, but this is just my opinion.

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