Based on a patch by Stefan Dösinger. This is more flexible, and allows
the shader backend implementation to be simpler, since it doesn't have
to know about specific formats. The next patch makes use of this.
Some stateblock parameters have to be compiled into the GL pixel
shader code, like lines for pixelformat fixups. This leads to problems
when applications switch those settings, requiring a recompilation of
the shader. This patch enables wined3d to have multiple GL shaders for
a D3D shader(pixel shaders only so far) to handle this more
efficiently.
This was suggested by Ivan quite a while ago, and we need it to better
handle conflicting texture format corrections and similar stateblock
value changes which until now required a recompilation of the entire
shader
A number of considerations contribute to this:
1) The shader backend knows best which shader(s) it needs. GLSL needs
both, arb only one
2) The shader backend may pass some parameters to the compilation
code(e.g. which pixel format fixup to use)
3) The structures used in (2) are different in vs and ps, so a
baseshader::Compile won't work
4) The structures in (2) are wined3d-private structures, so
having a public method in the vtable won't work(its a bad idea
anyway).
The code here skipped constant loading when a pixel shader was in use,
and only reloaded them on ffp use if the shader implementation used
ARB too. This way a e.g. texfactor change could get lost if GLSL
shaders are used, and the texfactor changed while a pixel shader was
in use.
GL_ATI_envmap_bumpmap provides two things: Signed V8U8 pixel formats,
and bump mapping. The extension is only supported on fglrx, and this
driver also supports GL_ARB_fragment_program. Thus the bump mapping
code is never used on any driver out there. Furthermore, if it is
used, it tends to crash the driver
The signed pixel format is used, as it can be used by pixel shaders or
the ARBfp replacement. However, the format is broken in fglrx, and
negative values are clamped to 0.0. This results in test
failures. WineD3D has an alternative codepath using scale+bias to
enable V8U8 using a standard signed RGB which works correctly on
fglrx.
The current code properly enabled/disabled GL_ARB_fragment_program
after a depth blit, but it did not restore the bound fragment program
properly. This leads to problems if a depth blit was done between two
draws without any change of the fragment processing settings.
This is the prefered format of many codecs, and for some codecs this
is the only supported output format. As usual I try to handle all the
conversion in the GPU and keep the CPU involvement minimal to gain the
full performance of PBO transfers.
GL_ARB_fragment_program and GL_ATI_fragment_shader can disable
projected textures properly, and they can also handle
D3DTTFF_PROJECTED | D3DTTFF_COUNT3 properly.
Henri Verbeet