We all know that many Windows 98 games take advantage of the 3Dfx Glide API — in fact the widespread support for Glide was a big reason to buy a Voodoo card back in the 90s.
But do you know that Glide games are supported in DOS too?
Here’s what you need to know.
There are two types of games
-
Statically linked games have their Voodoo support baked into the application binary. In short, the game is hardcoded to talk directly to the Voodoo hardware.
-
Dynamically linked games take advantage of the
glide2x.ovllibrary. When a Glide game starts up, it first looks for this file in the game directory, then starts to look through the directories specified in the%PATH.
Statically linked games
Because the Voodoo support is baked in, these games only support earlier Voodoo hardware — i.e. the Voodoo1 and Voodoo2 3D accelerator cards. Without these cards present, the game or PC will usually freeze.
Dynamically linked games
For these games, it’s good news: we can take advantage of the OVL abstraction to play these games on a Voodoo 3, 4 or even Voodoo 5 card!
All official Voodoo driver packages include a copy of glide2x.ovl. Just grab the appropriate version for your card, and place it in the game directory.
Environment variables
The Voodoo behaviour can be modified by setting DOS environment variables.
These can be set via a batch file, which you could run prior to launching your game:
REM ===== GLIDE ENVIRONMENT VARIABLES (ALL CARDS) =====
SET FX_GLIDE_LOD_DITHER=1
SET FX_GLIDE_SWAPINTERVAL=0
SET FX_GLIDE_NO_SPLASH=1
SET FX_GLIDE_ALLOC_COLOR=3
REM ===== VOODOO 1 ENVIRONMENT VARIABLES =====
SET SST_GRXCLK=50
SET SST_FT_CLK_DEL=0x4
SET SST_TF0_CLK_DEL=0x6
SET SST_TF1_CLK_DEL=0x6
SET SST_VIN_CLKDEL=0x1
SET SST_VOUT_CLKDEL=0x0
SET SST_FASTMEM=0
SET SST_TMUMEM_SIZE=2
SET SST_SCREENREFRESH=60
REM ===== VOODOO 2 ENVIRONMENT VARIABLES =====
SET SSTV2_GRXCLK=50
SET SSTV2_SWAP_EN_WAIT_ON_VSYNC=0
SET SSTV2_SCREENREFRESH=60
SET SSTV2_VIDEO_24BPP=1
SET SSTV2_FASTPCIRD=0
SET SSTV2_FASTMEM=0
SET SSTV2_SWAPINTERVAL=1
SET SSTV2_ANTIALIAS=1
SET SSTV2_SCREENREFRESH=60
SET SSTV2_REFRESH_512x384=60
SET SSTV2_REFRESH_640x400=60
SET SSTV2_REFRESH_640x480=60
SET SSTV2_REFRESH_800x600=60
SET SSTV2_GAMMA=1.7
SET SSTV2_RGAMMA=1.20
SET SSTV2_GGAMMA=1.20
SET SSTV2_BGAMMA=1.20
SET SSTV2_OVERLAYMODE=1
REM ==== VOODOO 3-5 ENVIRONMENT VARIABLES ====
SET SSTh3_GRXCLK=50
SET SSTh3_SWAP_EN_WAIT_ON_VSYNC=0
SET SSTh3_SCREENREFRESH=60
SET SSTh3_VIDEO_24BPP=1
SET SSTh3_FASTPCIRD=0
SET SSTh3_FASTMEM=0
SET SSTh3_SWAPINTERVAL=1
SET SSTh3_ANTIALIAS=1
SET SSTh3_SCREENREFRESH=60
SET SSTh3_REFRESH_512x384=60
SET SSTh3_REFRESH_640x400=60
SET SSTh3_REFRESH_640x480=60
SET SSTh3_REFRESH_800x600=60
SET SSTh3_GAMMA=1.7
SET SSTh3_RGAMMA=1.20
SET SSTh3_GGAMMA=1.20
SET SSTh3_BGAMMA=1.20
SET SSTH3_SLIDETECT=0
SET SSTh3_OVERLAYMODE=0
Find the full list (with explanations!) right here.
Running a Voodoo 1/2 and 3/4/5 in the same machine
This is possible, and perhaps desirable to play both newer and older Glide games. Find more details here.
Supported games
Statically linked games:
- Actua Soccer ‘96
- Battle Arena Toshinden
- EF2000: Tactcom
- Fatal Racing/Whiplash
- Starfighter 3000
Dynamically linked games:
- Descent II
- Tomb Raider
- Screamer 2
- XCar: Experimental Racing
Note: there are some compatibility problems even for these dynamically linked games. One example is Archimedean Dynasty.
Find more details here.
Troubleshooting individual games
Tomb Raider
For Tomb Raider, there are two patches available.
- The first is statically linked and works with Voodoo 1 cards only.
- The second (sometimes referred to as the Voodoo Rush patch), is dynamically linked and works with all Voodoo cards.
By default, the second patch is a little dark. Gamma can be adjusted using the environment variables above. This works well for Voodoo 1/2, but doesnt seem to work for Voodoo 3+
Find more details here and here.
