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.
This isn't used at all in the OpenGL shader cache, so we can remove it's
include here, meaning one less file needs to be recompiled if any
changes ever occur within that header.
core/memory.h is also not used within this file at all, so we can remove
it as well.
i965 (and probably all mesa drivers) require GL_PROGRAM_SEPARABLE when using
glProgramBinary. This is probably required by the standard but it's ignored by
permisive proprietary drivers.
Geometry shaders follow a pattern that results in out of bound reads.
This pattern is:
- VSETP to predicate
- Use that predicate to conditionally set a register a big number
- Use the register to access geometry shaders
At the time of writing this commit I don't know what's the intent of
this number. Some drivers argue about these out of bound reads. To avoid
this issue, input reads are guarded limiting reads to the highest
posible vertex input of the current topology (e.g. points to 1 and
triangles to 3).
Rather than have a transparent dependency, we can make it explicit in
the interface. This also gets rid of the need to put the core include in
a header.
* Added glObjectLabels for renderdoc for textures and shader programs
* Changed hardcoded "Texture" name to reflect the texture type instead
* Removed string initialize
- Fixed all warnings, for renderer_opengl items, which were indicating a
possible incorrect behavior from integral promotion rules and types
larger than those in which arithmetic is typically performed.
- Added const for variables where possible and meaningful.
- Added constexpr where possible.
The std::string generation with its malloc and free requirement
was a noticeable overhead. Also switch to an ordered_map to
avoid the std::hash call. As those maps usually have a size of
two elements, the lookup time shall not matter.
Given std::vector is a type with a non-trivial destructor, this
variable cannot be optimized away by the compiler, even if unused.
Because of that, something that was intended to be fairly lightweight,
was actually allocating 32KB and deallocating it at the end of the
function.