Remove false commentary. Not dividing by 4 the size of shared memory is
not a hack; it describes the number of integers, not bytes.
While we are at it sort the generated code to put preprocessor lines on
the top.
Add missing new-line. This caused shaders using local memory and shared
memory to inject a preprocessor GLSL line after an expression (resulting
in invalid code).
It looked like this:
shared uint smem[8];#define LOCAL_MEMORY_SIZE 16
It should look like this (addressed by this commit):
shared uint smem[8];
\#define LOCAL_MEMORY_SIZE 16
The current shared memory size seems to be smaller than what the game
actually uses. This makes Nvidia's driver consistently blow up; in the
case of FE3H it made it explode on Qt's SwapBuffers while SDL2 worked
just fine. For now keep this hack since it's still progress over the
previous hardcoded shared memory size.
Drop the usage of ARB_compute_variable_group_size and specialize compute
shaders instead. This permits compute to run on AMD and Intel
proprietary drivers.
Implement VOTE using Nvidia's intrinsics. Documentation about these can
be found here
https://developer.nvidia.com/reading-between-threads-shader-intrinsics
Instead of using portable ARB instructions I opted to use Nvidia
intrinsics because these are the closest we have to how Tegra X1
hardware renders.
To stub VOTE on non-Nvidia drivers (including nouveau) this commit
simulates a GPU with a warp size of one, returning what is meaningful
for the instruction being emulated:
* anyThreadNV(value) -> value
* allThreadsNV(value) -> value
* allThreadsEqualNV(value) -> true
ballotARB, also known as "uint64_t(activeThreadsNV())", emits
VOTE.ANY Rd, PT, PT;
on nouveau's compiler. This doesn't match exactly to Nvidia's code
VOTE.ALL Rd, PT, PT;
Which is emulated with activeThreadsNV() by this commit. In theory this
shouldn't really matter since .ANY, .ALL and .EQ affect the predicates
(set to PT on those cases) and not the registers.
This commit implements gl_ViewportIndex and gl_Layer in vertex and
geometry shaders. In the case it's used in a vertex shader, it requires
ARB_shader_viewport_layer_array. This extension is available on AMD and
Nvidia devices (mesa and proprietary drivers), but not available on
Intel on any platform. At the moment of writing this description I don't
know if this is a hardware limitation or a driver limitation.
In the case that ARB_shader_viewport_layer_array is not available,
writes to these registers on a vertex shader are ignored, with the
appropriate logging.
