MiniGL Drivers - 5/23/98 GOLD

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Rendition®* MiniGL Drivers - 5/23/98 GOLD

This ZIP file contains unsupported "Mini" OpenGL drivers for boards based upon the V1000 and V2x00 chips from Rendition. These drivers allow you to play Quake and Quake descended games, as well as other OpenGL games that do not require a full OpenGL ICD.

Major new features in this release of the MiniGL include H3D stereo glasses support, triple buffering, line doubled stereo support, vertex array optimizations, gamma table support, and point parameter extension support.

This release should be considered "gold" - all major issues have been resolved and to-do items completed. If any new serious bugs are discovered however, this MiniGL may once again be updated.

There are four files:

readme.txt: This file.
opengl32.dll: The OpenGL "mini" driver.
v2000gl.uc: The MiniGL microcode file for the V2x00.
v1000gl.uc: The MiniGL microcode file for the V1x00.

To install this driver:

Copy the v2000gl.uc or v1000gl.uc file to your windows\system directory, depending upon which chip you have.

Copy the opengl32.dll to your OpenGL game's directory. It is not recommended that you put this file in your windows\system directory, because it does not support the entire OpenGL API. Applications that require unsupported functions may crash if you copy this file to windows\system.

Configuration Instructions

This miniGL uses registry entries to modify behavior. Two new features that are affected by registry entries are:

(1) Triple buffering (when you are a full screen app, and ask for double buffering you actually have 3 buffers allocated - 6 if stereo - in a transparent fashion to the user). Triple buffering drastically reduces the time the graphics chip spends waiting for the vertical sync between frames. An offshoot of this is that it is no longer necessary to have the highest refresh rate to see maximum performance. On the other hand we can run at the lowest comfortable refresh rate, having the CRT controller access the framebuffer much less frequently and thereby freeing up memory bandwidth for rendering. So setting the lowest refresh rate gives best results when triple buffering is enabled. When it is not, then highest refresh enabled. When it is not, then highest refresh rate gives you the fastest results.

(2) Line doubled stereo. When viewing stereo, if the vertical resolution is halved the eye gets fooled into believing that there is almost as much resolution as in a non-stereo buffer with twice the vertical resolution. Halving the vertical resolution, halves the memory/rendering bandwidths required. So we are able to run almost as fast as the non-stereo case (not quite true if the geometry is the bottleneck).

Triple buffering is on by default. Stereo line doubling is off by default. There is no need to edit your registry if you do not wish to change this default behavior.

To change these settings, use regedit to add to following to the local machine registry under "Software\Rendition\OpenGL":

TripleBuffering 0 or 1 disable/enable triple buffering
StereoLineDouble 0 or 1 disable/enable line doubling in stereo

Note: The registry entries should be entered exactly as shown, and the data values should be DWORD's. 0 = Off. 1 = On.

Notes

Triple buffering uses 50% more frame buffer memory than double buffering. On a 4MB card, memory may be scarce in some applications. If you notice any performance problems with triple buffering enabled, you may wish to disable it or run at a lower resolution. 4MB card, memory may be scarce in some applications. If you notice any performance problems with triple buffering enabled, you may wish to disable it or run at a lower resolution.

Quake 1 assumes a double-buffered screen, and when run with triple buffering may exhibit flashing. At the console "set gl_triplebuffer 1" to fix this.

To turn on stereo in Quake 2, type "set cl_stereo 1", "set gl_ztrick 0", followed by a "vidrestart".

With line-doubling enabled, the default console font in Quake 2 is very difficult to read. You may wish to experiment with different fonts, or to turn off stereo mode temporarily while working with the console.

The V1000 is not as powerful nor as well suited to running OpenGL apps as the V2K. Even so, at low resolutions and with the gun hidden (set cl_gun 0), we have experienced quite acceptable death match performance.

Again, these drivers are unsupported by Rendition*.
End-users are recommended to use drivers provided by their board manufacturer to ensure that they can obtain full support.

* Note: Rendition is now part of the Integrated Products Group of Micron Technology, Inc.