only on Battle Race , Fatal Racing, Whiplash. because those 3 are not officially supported by PCI. i think black screen is caused by VRIT*.CGL driver when we use them unofficially, and on VLB its not happens.
All the other games are ok.
So every time when API activates it switches to other video mode. In case where we have 2 cards , primary VGA and 3d blaster pci secondary, all the API activations turn on video output on 3d b PCI, primary VGA works all time. in some games you can see logs on Primary and 3D on secondary.
in case when you have primary only 3d b pci , the API have higher priority to draw on top of everything else, in case of Whiplash/Fatal Racing i guess API doesn't get to be deactivating that why after single intro of race we do not see menu, because API still active and only shows black screen, to do fast 3d rendering for next scenes, without re-initialization API.
Hi-Octane since it beta patch which actually seems working great it have odd thing , Primary+Secondary causes Secondary (3d b PCI) to not turn off video signal, and we see last frame of game. in single PCI , that last frame doesn't prevent VGA to draw anything else.
the CGL on VLB in some games are statically linked in game files in exe , so those will require exact same function addresses , making wrapping more difficult, much like low level emulation . The other CGL files , if they whenever will be decompiled could be recompiled to have any addresses, even probably make CGL to work on other 3d capable video cards or rendition verite which are non creative.
i have Cirrus Logic CLGD5464 which also CGL compatible and L3D*.CGL files used.
gona have Permedia + IBM RAM DAC which also CGL compatible and PDL*.CGL is used.
So CGL is key to access 3d functions on any video card supported by CGL driver.
VLB is like voodoo2 uses cable passthrough from primary VGA (2d) to VLB(3D) VLB outs to monitor , if there is no 3d than it passtru 2d from primary card, if there is 3d it output video from VLB card. Much like voodoo2 you know.
ask furan , he made partial CGL API reconstruction.
CGL files probably seek Vendor ID and Device ID to find CGL compatible card to knew where it can be activated.
Hey have idea to try TWO cards any 2d and CLGD5464 as 2nd and see if that statement is right.
all those is what i guess.
EDIT:
Nope cirrus Logics can't be used as 2nd card.
The battle arena toshinden gives error twice:
DISPLAY LIST OVERRUN
Rebel Moon is activating CGL api on matrox mystique.
Whaat, it means if clgd5464 is present than condition of veryfing vendor ID and device ID passed, than CGL gets activated, and tries to render on matrox, clgd is 2nd card, with a lot of glitches it works game is playable.