// Copyright 2018 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <tuple>
#include <unordered_map>
#include <boost/functional/hash.hpp>
#include <glad/glad.h>
#include "video_core/renderer_opengl/gl_resource_manager.h"
#include "video_core/renderer_opengl/gl_shader_gen.h"
#include "video_core/renderer_opengl/maxwell_to_gl.h"
namespace GLShader {
/// Number of OpenGL texture samplers that can be used in the fragment shader
static constexpr size_t NumTextureSamplers = 32;
using Tegra::Engines::Maxwell3D;
namespace Impl {
void SetShaderUniformBlockBindings(GLuint shader);
void SetShaderSamplerBindings(GLuint shader);
} // namespace Impl
/// Uniform structure for the Uniform Buffer Object, all vectors must be 16-byte aligned
// NOTE: Always keep a vec4 at the end. The GL spec is not clear wether the alignment at
// the end of a uniform block is included in UNIFORM_BLOCK_DATA_SIZE or not.
// Not following that rule will cause problems on some AMD drivers.
struct MaxwellUniformData {
void SetFromRegs(const Maxwell3D::State::ShaderStageInfo& shader_stage);
// TODO(Subv): Use this for something.
};
// static_assert(sizeof(MaxwellUniformData) == 1024, "MaxwellUniformData structure size is
// incorrect");
static_assert(sizeof(MaxwellUniformData) < 16384,
"MaxwellUniformData structure must be less than 16kb as per the OpenGL spec");
class OGLShaderStage {
public:
OGLShaderStage() = default;
void Create(const char* source, GLenum type) {
OGLShader shader;
shader.Create(source, type);
program.Create(true, shader.handle);
Impl::SetShaderUniformBlockBindings(program.handle);
Impl::SetShaderSamplerBindings(program.handle);
}
GLuint GetHandle() const {
return program.handle;
}
private:
OGLProgram program;
};
// TODO(wwylele): beautify this doc
// This is a shader cache designed for translating PICA shader to GLSL shader.
// The double cache is needed because diffent KeyConfigType, which includes a hash of the code
// region (including its leftover unused code) can generate the same GLSL code.
template <typename KeyConfigType,
std::string (*CodeGenerator)(const ShaderSetup&, const KeyConfigType&), GLenum ShaderType>
class ShaderCache {
public:
ShaderCache() = default;
GLuint Get(const KeyConfigType& key, const ShaderSetup& setup) {
auto map_it = shader_map.find(key);
if (map_it == shader_map.end()) {
std::string program = CodeGenerator(setup, key);
auto [iter, new_shader] = shader_cache.emplace(program, OGLShaderStage{});
OGLShaderStage& cached_shader = iter->second;
if (new_shader) {
cached_shader.Create(program.c_str(), ShaderType);
}
shader_map[key] = &cached_shader;
return cached_shader.GetHandle();
} else {
return map_it->second->GetHandle();
}
}
private:
std::unordered_map<KeyConfigType, OGLShaderStage*> shader_map;
std::unordered_map<std::string, OGLShaderStage> shader_cache;
};
using VertexShaders = ShaderCache<MaxwellVSConfig, &GenerateVertexShader, GL_VERTEX_SHADER>;
using FragmentShaders = ShaderCache<MaxwellFSConfig, &GenerateFragmentShader, GL_FRAGMENT_SHADER>;
class ProgramManager {
public:
ProgramManager() {
pipeline.Create();
}
void UseProgrammableVertexShader(const MaxwellVSConfig& config, const ShaderSetup setup) {
current.vs = vertex_shaders.Get(config, setup);
}
void UseProgrammableFragmentShader(const MaxwellFSConfig& config, const ShaderSetup setup) {
current.fs = fragment_shaders.Get(config, setup);
}
void UseTrivialGeometryShader() {
current.gs = 0;
}
void ApplyTo(OpenGLState& state) {
// Workaround for AMD bug
glUseProgramStages(pipeline.handle,
GL_VERTEX_SHADER_BIT | GL_GEOMETRY_SHADER_BIT | GL_FRAGMENT_SHADER_BIT,
0);
glUseProgramStages(pipeline.handle, GL_VERTEX_SHADER_BIT, current.vs);
glUseProgramStages(pipeline.handle, GL_GEOMETRY_SHADER_BIT, current.gs);
glUseProgramStages(pipeline.handle, GL_FRAGMENT_SHADER_BIT, current.fs);
state.draw.shader_program = 0;
state.draw.program_pipeline = pipeline.handle;
}
private:
struct ShaderTuple {
GLuint vs = 0, gs = 0, fs = 0;
bool operator==(const ShaderTuple& rhs) const {
return std::tie(vs, gs, fs) == std::tie(rhs.vs, rhs.gs, rhs.fs);
}
struct Hash {
std::size_t operator()(const ShaderTuple& tuple) const {
std::size_t hash = 0;
boost::hash_combine(hash, tuple.vs);
boost::hash_combine(hash, tuple.gs);
boost::hash_combine(hash, tuple.fs);
return hash;
}
};
};
ShaderTuple current;
VertexShaders vertex_shaders;
FragmentShaders fragment_shaders;
std::unordered_map<ShaderTuple, OGLProgram, ShaderTuple::Hash> program_cache;
OGLPipeline pipeline;
};
} // namespace GLShader