On the Texture Memory Problem :
I'm not sure about the Banshee, but all Cards from Voodoo3 upwards seem to have 'backup' ways to tackle this problem :
For example, in 3D Mark 2000, 3dfx cards can do the 64MB Texture Memory test (even a Voodoo3).
Performance at that point is down to a crawl, but either the Engine, or the Driver already has the capability to swap even extreme amounts of Memory.
Same with UT2003, which will run even with very high Texture settings on a Voodoo4 or 5. Again, the drastic breakpoint in performance shows when Texture swapping begins, and can quickly slow performance quite dramatically.
Another observation (Large Textures) :
I used to play around with an old 3D Screensaver (OpenGL), that simply took the Desktop picture, stuff it into a Texture, and use it for 3D.
Amazingly, the Voodoo3 even accepted 1024x1024 Textures (the Desktop Resolution at that time).
Only problem that was more than apparent, was that (again, either the Engine, or the Driver) took an extreme time to convert/filter the oversized Texture downto a usable 256x256. This process took several seconds (!). Once it was done, though, everything was back to normal performance.
The Image now displayed in the Texture was 256x256, but looked completely Antialiased (alot of subpixels were used for filtering), so that details were blurred, but still visible (text was still readable).
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These are effects which I never fully understood.
The Cards basically were and are doing things that they basically are not supposed to be capable of.
I could tell that they worked reproduceably, but am still today unable to fully explain a) why they work, and b) what was responsible for the fact, that they work.
As said in another Thread, I
believe a 'dirty' 3D engine doing no capability check for those features (Multitexturing, Texture Size, Video Memory) can initialize/use all those effects even on uncapable/limited Cards, yet they work (possibly by workarounds Driver-sized, with a hefty performance hit obviously).
Only those Engines, who correctly detect the missing caps, and logically reduce the 3D Effects/ Level of detail, usually cause upto, and including severe loss in Visual Quality, or fail/deny to initialize alltogether
Can't proof that this is 100.0% correct, but was the only viable Explanation I could give to myself over the years...
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3D Analyzer was on its best way to do exactly that (at least for Direct3D), but seems it is not being developed alot anymore
The concept, however, would have worked for all API's, and would have indeed even allowed for Full, Partial (substitute Rendering techniques), or NUL-Rendering (as currently implemented for most functions).
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