VQuake (short for
Verité Quake) is a port of
Id Software's
Quake for the
Rendition Verité (V1000) graphics chipset. It was released shortly after the game itself and was bundled with the
3D Blaster PCI (
Creative Labs's Rendition-powered card). At the time (late
1996) there were a number of 3D accelerator chipsets coming onto the market, most of which used their manufacturer's proprietary
APIs (such as
Glide or
Speedy3D), necessitating specific versions of games to be developed for each chipset. (A similar situation has arisen with soundcards a few years before, before the
Sound Blaster won out - one of the factors that led people to believe
Creative Labs would emerge victorious in this
format war as well.)
During Quake's development, Id Software identified the Verité chipset as offering the best price-performance ratio of any consumer 3D solution on the market, and so made it the first chipset to benefit from a dedicated version of Quake. (The actual reason might have had more to do with Creative Labs' deal to bundle shareware Quake with their cards, or possibly an offer of free workstations from Intergraph, another company who had adopted Rendition's technology.)
VQuake introduces a number of enhancements in image quality and performance over software-rendered DOS Quake. The colour depth is increased to 16 bits per pixel (although Quake's textures remain 8-bit). All texture mapping is performed with bilinear filtering, and the dithering on the filtering can be toggled. (With it turned on, walls turn into out-of-focus swirls of colour at close range; turned off, they look like an early attempt at NPR oil painting.) Mipmapping could also be tweaked, to alter the range at which textures would be replaced with lower resolution versions. The amplitude and frequency of the water warping effect could also be changed. Most impressively, true antialiasing could be applied to the edges of some or all polygons. It was also possible to antialias particles (actually, replacing the squares with hardware-drawn filled circles). It is also worth noting that, unlike GLQuake, VQuake retains Quake's dynamic lighting effects.
VQuake allowed the PCs of the time (first generation Pentiums) to run Quake at significantly higher resolutions and framerates than the software version could manage.
After VQuake was done, Id Software ported Quake to OpenGL, primarily catering to the feature set of the 3dfx Voodoo (1) chipset. GLQuake was blisteringly fast compared to software Quake or even VQuake, and used smoother trilinear filtering on its textures. The image quality was rather fuzzier, however and GLQuake lacked some of the other niceties of VQuake (its particles were odd pixellated blobs, and the less said about its 'light flare' effects the better). However, speed was deemed to be the more important factor, so as a result GLQuake was a resounding success, the Voodoo chipset continued to gain momentum with support in many more games, and the rest is history.
VQuake uses the Speedy3D API. It includes a microcode file which is copied to the V1000 (a programmable RISC chip) at launch. A great deal of the graphics processing still uses the CPU and system RAM, the Verité texture-maps the geometry that is passed to it by the CPU. Because the workload of the CPU and the graphics chip are rather uneven, beyond a certain resolution and CPU speed, the Verité ironically becomes a serious bottleneck. As the Verité card only has 3Mb of memory available to store textures, it is possible for it to run out of space and textures to become corrupted. A workaround for this was to bind the 'Flush' console command to a key, allowing the player to prompt the game to rebuild the texture cache if corruption appeared.
Things to check out in VQuake include the appearance and lighting of the double barreled shotgun model, decorative features with large textures (e.g. level arches, the Jesus), the sky, antialiased nails in flight, the Necropolis, the DM4 and DM5 maps, and complex, neutrally-textured geometry at lower screen resolutions with antialiasing turned on.
Note: Because the Rendition Verité chipset family is not officially supported by Windows 2000/XP (and DOS Quake doesn't run in NT-based Windows anyway), you'll have to run VQuake from DOS.
References
Michael Abrash's Graphics Programming Black Book (Special Edition) p. 1287-88
The Quake Info Pool (http://www.inside3d.com/qip/q1/console.htm#VQuake)