From 420cc13248350ef5c2d19e0b961cb4185cd16a8a Mon Sep 17 00:00:00 2001 From: ReinUsesLisp Date: Sun, 17 May 2020 22:32:49 -0300 Subject: renderer_opengl: Add assembly program code paths Add code required to use OpenGL assembly programs based on NV_gpu_program5. Decompilation for ARB programs is intended to be added in a follow up commit. This does **not** include ARB decompilation and it's not in an usable state. The intention behind assembly programs is to reduce shader stutter significantly on drivers supporting NV_gpu_program5 (and other required extensions). Currently only Nvidia's proprietary driver supports these extensions. Add a UI option hidden for now to avoid people enabling this option accidentally. This code path has some limitations that OpenGL compatibility doesn't have: - NV_shader_storage_buffer_object is limited to 16 entries for a single OpenGL context state (I don't know if this is an intended limitation, an specification issue or I am missing something). Currently causes issues on The Legend of Zelda: Link's Awakening. - NV_parameter_buffer_object can't bind buffers using an offset different to zero. The used workaround is to copy to a temporary buffer (this doesn't happen often so it's not an issue). On the other hand, it has the following advantages: - Shaders build a lot faster. - We have control over how floating point rounding is done over individual instructions (SPIR-V on Vulkan can't do this). - Operations on shared memory can be unsigned and signed. - Transform feedbacks are dynamic state (not yet implemented). - Parameter buffers (uniform buffers) are per stage, matching NVN and hardware's behavior. - The API to bind and create assembly programs makes sense, unlike ARB_separate_shader_objects. --- src/video_core/renderer_opengl/gl_device.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'src/video_core/renderer_opengl/gl_device.h') diff --git a/src/video_core/renderer_opengl/gl_device.h b/src/video_core/renderer_opengl/gl_device.h index a55050cb5..e915dbd86 100644 --- a/src/video_core/renderer_opengl/gl_device.h +++ b/src/video_core/renderer_opengl/gl_device.h @@ -88,6 +88,10 @@ public: return has_fast_buffer_sub_data; } + bool UseAssemblyShaders() const { + return use_assembly_shaders; + } + private: static bool TestVariableAoffi(); static bool TestPreciseBug(); @@ -107,6 +111,7 @@ private: bool has_precise_bug{}; bool has_broken_compute{}; bool has_fast_buffer_sub_data{}; + bool use_assembly_shaders{}; }; } // namespace OpenGL -- cgit v1.2.3