wine users - Mar 2008 - Feature request: Shader Emulation for Old Graphics Cards

What I would like to see is maybe some check boxes in winecfg such as
"emulate shaders [ ] v 1.1 [ ] v 1.4 [ ] v. 2.0 [ ] v 3.0"

Maybe this would be too much work and I don't know what I'm asking. But
I think fast emulation is possible using open source. This would allow many
modern programs to be run on older hardware and I think it would draw in more
people and increase interest in the wine project.

On 28/03/2008, hellork <wineforum-user at winehq.org> wrote:
> What I would like to see is maybe some check boxes in winecfg such as
"emulate shaders [ ] v 1.1 [ ] v 1.4 [ ] v. 2.0 [ ] v 3.0"
>  Maybe this would be too much work and I don't know what I'm
asking. But I think fast emulation is possible using open source. This would
allow many modern programs to be run on older hardware and I think it would draw
in more people and increase interest in the wine project.

The *proper* place for this would be in the graphics card driver or in
Mesa (OpenGL emulator), in X itself. I don't know how feasible that
would be in those places. Emulation is possible, but it's nothing like
as fast as the dedicated hardware of a GPU.


- d.

hellork wrote:
> What I would like to see is maybe some check boxes in winecfg such as
"emulate shaders [ ] v 1.1 [ ] v 1.4 [ ] v. 2.0 [ ] v 3.0"
> 
> Maybe this would be too much work and I don't know what I'm asking.
But I think fast emulation is possible using open source. This would allow many
modern programs to be run on older hardware and I think it would draw in more
people and increase interest in the wine project.
This is not possible. If old card does not support new shaders, emulating them
in software will be 100's times slover then new card can.
There are reasons why GPUs were made and we using them instead of good 'ol
VGA video cards without any acceleration.

I'd like to see how would you emulate conditions, cycles and other
"flow control" instructions. Or float point formats?
You can't (in the GPU itself at least). And doing it outside the GPU is
prohibitively slow.

Obviously emulation would not have to be 100% accurate or it would indeed be
significantly slower. Perhaps a quality slider could be implemented such that
certain features could be dropped, stubbed or filled in with gray texture for
example. Some systems, namely laptops or surplus servers, can have several fast
CPUs but are lacking in the GPU department for various reasons (expensive or
built into the motherboard) and can't be replaced easily or economically. In
these cases, some software fallback ability would be useful. Perhaps the
checkbox idea was unnecessary and software emulation could be automatic (Perhaps
with a debug message: shader version %d not available, attempting partial
emulation with shader_emulator.c ...).

People you have no concepts of the shaders yet you talk like you know exactly
what they are and how they work. This is pointless. No it is impossible to
emulate such stuff unless you are ok with having 1/100 FPS.  But if you are ok
with that, what are you doing with this modern HW in the first place? Why
aren't you still using i386 based PC?