Merge pull request #3645 from wwylele/shader-manager

renderer_opengl: refactor shader & program objects and add shader manager for rasterizer

src/video_core/CMakeLists.txt

@@ -32,6 +32,8 @@ add_library(video_core STATIC
     renderer_opengl/gl_shader_decompiler.h
     renderer_opengl/gl_shader_gen.cpp
     renderer_opengl/gl_shader_gen.h
+    renderer_opengl/gl_shader_manager.cpp
+    renderer_opengl/gl_shader_manager.h
     renderer_opengl/gl_shader_util.cpp
     renderer_opengl/gl_shader_util.h
     renderer_opengl/gl_state.cpp

src/video_core/renderer_opengl/gl_rasterizer.cpp

@@ -177,6 +177,9 @@ RasterizerOpenGL::RasterizerOpenGL() : shader_dirty(true) {
     glActiveTexture(TextureUnits::ProcTexDiffLUT.Enum());
     glTexBuffer(GL_TEXTURE_BUFFER, GL_RGBA32F, proctex_diff_lut_buffer.handle);
 
+    shader_program_manager =
+        std::make_unique<ShaderProgramManager>(GLAD_GL_ARB_separate_shader_objects);
+
     glEnable(GL_BLEND);
 
     SyncEntireState();
@@ -490,6 +493,11 @@ void RasterizerOpenGL::DrawTriangles() {
     state.scissor.height = draw_rect.GetHeight();
     state.Apply();
 
+    shader_program_manager->UseTrivialVertexShader();
+    shader_program_manager->UseTrivialGeometryShader();
+    shader_program_manager->ApplyTo(state);
+    state.Apply();
+
     // Draw the vertex batch
     size_t max_vertices = 3 * (VERTEX_BUFFER_SIZE / (3 * sizeof(HardwareVertex)));
     for (size_t base_vertex = 0; base_vertex < vertex_batch.size(); base_vertex += max_vertices) {
@@ -1258,95 +1266,7 @@ void RasterizerOpenGL::SamplerInfo::SyncWithConfig(
 
 void RasterizerOpenGL::SetShader() {
     auto config = GLShader::PicaShaderConfig::BuildFromRegs(Pica::g_state.regs);
-    std::unique_ptr<PicaShader> shader = std::make_unique<PicaShader>();
+    shader_program_manager->UseFragmentShader(config);
-
-    // Find (or generate) the GLSL shader for the current TEV state
-    auto cached_shader = shader_cache.find(config);
-    if (cached_shader != shader_cache.end()) {
-        current_shader = cached_shader->second.get();
-
-        state.draw.shader_program = current_shader->shader.handle;
-        state.Apply();
-    } else {
-        LOG_DEBUG(Render_OpenGL, "Creating new shader");
-
-        shader->shader.Create(GLShader::GenerateVertexShader().c_str(),
-                              GLShader::GenerateFragmentShader(config).c_str());
-
-        state.draw.shader_program = shader->shader.handle;
-        state.Apply();
-
-        // Set the texture samplers to correspond to different texture units
-        GLint uniform_tex = glGetUniformLocation(shader->shader.handle, "tex[0]");
-        if (uniform_tex != -1) {
-            glUniform1i(uniform_tex, TextureUnits::PicaTexture(0).id);
-        }
-        uniform_tex = glGetUniformLocation(shader->shader.handle, "tex[1]");
-        if (uniform_tex != -1) {
-            glUniform1i(uniform_tex, TextureUnits::PicaTexture(1).id);
-        }
-        uniform_tex = glGetUniformLocation(shader->shader.handle, "tex[2]");
-        if (uniform_tex != -1) {
-            glUniform1i(uniform_tex, TextureUnits::PicaTexture(2).id);
-        }
-        uniform_tex = glGetUniformLocation(shader->shader.handle, "tex_cube");
-        if (uniform_tex != -1) {
-            glUniform1i(uniform_tex, TextureUnits::TextureCube.id);
-        }
-
-        // Set the texture samplers to correspond to different lookup table texture units
-        GLint uniform_lut = glGetUniformLocation(shader->shader.handle, "lighting_lut");
-        if (uniform_lut != -1) {
-            glUniform1i(uniform_lut, TextureUnits::LightingLUT.id);
-        }
-
-        GLint uniform_fog_lut = glGetUniformLocation(shader->shader.handle, "fog_lut");
-        if (uniform_fog_lut != -1) {
-            glUniform1i(uniform_fog_lut, TextureUnits::FogLUT.id);
-        }
-
-        GLint uniform_proctex_noise_lut =
-            glGetUniformLocation(shader->shader.handle, "proctex_noise_lut");
-        if (uniform_proctex_noise_lut != -1) {
-            glUniform1i(uniform_proctex_noise_lut, TextureUnits::ProcTexNoiseLUT.id);
-        }
-
-        GLint uniform_proctex_color_map =
-            glGetUniformLocation(shader->shader.handle, "proctex_color_map");
-        if (uniform_proctex_color_map != -1) {
-            glUniform1i(uniform_proctex_color_map, TextureUnits::ProcTexColorMap.id);
-        }
-
-        GLint uniform_proctex_alpha_map =
-            glGetUniformLocation(shader->shader.handle, "proctex_alpha_map");
-        if (uniform_proctex_alpha_map != -1) {
-            glUniform1i(uniform_proctex_alpha_map, TextureUnits::ProcTexAlphaMap.id);
-        }
-
-        GLint uniform_proctex_lut = glGetUniformLocation(shader->shader.handle, "proctex_lut");
-        if (uniform_proctex_lut != -1) {
-            glUniform1i(uniform_proctex_lut, TextureUnits::ProcTexLUT.id);
-        }
-
-        GLint uniform_proctex_diff_lut =
-            glGetUniformLocation(shader->shader.handle, "proctex_diff_lut");
-        if (uniform_proctex_diff_lut != -1) {
-            glUniform1i(uniform_proctex_diff_lut, TextureUnits::ProcTexDiffLUT.id);
-        }
-
-        current_shader = shader_cache.emplace(config, std::move(shader)).first->second.get();
-
-        GLuint block_index = glGetUniformBlockIndex(current_shader->shader.handle, "shader_data");
-        if (block_index != GL_INVALID_INDEX) {
-            GLint block_size;
-            glGetActiveUniformBlockiv(current_shader->shader.handle, block_index,
-                                      GL_UNIFORM_BLOCK_DATA_SIZE, &block_size);
-            ASSERT_MSG(block_size == sizeof(UniformData),
-                       "Uniform block size did not match! Got {}, expected {}",
-                       static_cast<int>(block_size), sizeof(UniformData));
-            glUniformBlockBinding(current_shader->shader.handle, block_index, 0);
-        }
-    }
 }
 
 void RasterizerOpenGL::SyncClipEnabled() {

src/video_core/renderer_opengl/gl_rasterizer.h

@@ -8,12 +8,10 @@
 #include <cstddef>
 #include <cstring>
 #include <memory>
-#include <unordered_map>
 #include <vector>
 #include <glad/glad.h>
 #include "common/bit_field.h"
 #include "common/common_types.h"
-#include "common/hash.h"
 #include "common/vector_math.h"
 #include "core/hw/gpu.h"
 #include "video_core/pica_state.h"
@@ -25,13 +23,14 @@
 #include "video_core/regs_texturing.h"
 #include "video_core/renderer_opengl/gl_rasterizer_cache.h"
 #include "video_core/renderer_opengl/gl_resource_manager.h"
-#include "video_core/renderer_opengl/gl_shader_gen.h"
+#include "video_core/renderer_opengl/gl_shader_manager.h"
 #include "video_core/renderer_opengl/gl_state.h"
 #include "video_core/renderer_opengl/gl_stream_buffer.h"
 #include "video_core/renderer_opengl/pica_to_gl.h"
 #include "video_core/shader/shader.h"
 
 struct ScreenInfo;
+class ShaderProgramManager;
 
 class RasterizerOpenGL : public VideoCore::RasterizerInterface {
 public:
@@ -52,12 +51,6 @@ public:
     bool AccelerateDisplay(const GPU::Regs::FramebufferConfig& config, PAddr framebuffer_addr,
                            u32 pixel_stride, ScreenInfo& screen_info) override;
 
-    /// OpenGL shader generated for a given Pica register state
-    struct PicaShader {
-        /// OpenGL shader resource
-        OGLShader shader;
-    };
-
 private:
     struct SamplerInfo {
         using TextureConfig = Pica::TexturingRegs::TextureConfig;
@@ -121,47 +114,6 @@ private:
         GLfloat view[3];
     };
 
-    struct LightSrc {
-        alignas(16) GLvec3 specular_0;
-        alignas(16) GLvec3 specular_1;
-        alignas(16) GLvec3 diffuse;
-        alignas(16) GLvec3 ambient;
-        alignas(16) GLvec3 position;
-        alignas(16) GLvec3 spot_direction; // negated
-        GLfloat dist_atten_bias;
-        GLfloat dist_atten_scale;
-    };
-
-    /// 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 UniformData {
-        GLint framebuffer_scale;
-        GLint alphatest_ref;
-        GLfloat depth_scale;
-        GLfloat depth_offset;
-        GLint scissor_x1;
-        GLint scissor_y1;
-        GLint scissor_x2;
-        GLint scissor_y2;
-        alignas(16) GLvec3 fog_color;
-        alignas(8) GLvec2 proctex_noise_f;
-        alignas(8) GLvec2 proctex_noise_a;
-        alignas(8) GLvec2 proctex_noise_p;
-        alignas(16) GLvec3 lighting_global_ambient;
-        LightSrc light_src[8];
-        alignas(16) GLvec4 const_color[6]; // A vec4 color for each of the six tev stages
-        alignas(16) GLvec4 tev_combiner_buffer_color;
-        alignas(16) GLvec4 clip_coef;
-    };
-
-    static_assert(
-        sizeof(UniformData) == 0x460,
-        "The size of the UniformData structure has changed, update the structure in the shader");
-    static_assert(sizeof(UniformData) < 16384,
-                  "UniformData structure must be less than 16kb as per the OpenGL spec");
-
     /// Syncs entire status to match PICA registers
     void SyncEntireState();
 
@@ -269,8 +221,6 @@ private:
 
     std::vector<HardwareVertex> vertex_batch;
 
-    std::unordered_map<GLShader::PicaShaderConfig, std::unique_ptr<PicaShader>> shader_cache;
-    const PicaShader* current_shader = nullptr;
     bool shader_dirty;
 
     struct {
@@ -285,6 +235,8 @@ private:
         bool dirty;
     } uniform_block_data = {};
 
+    std::unique_ptr<ShaderProgramManager> shader_program_manager;
+
     std::array<SamplerInfo, 3> texture_samplers;
     OGLVertexArray vertex_array;
     static constexpr size_t VERTEX_BUFFER_SIZE = 128 * 1024 * 1024;

src/video_core/renderer_opengl/gl_rasterizer_cache.h

@@ -377,7 +377,7 @@ private:
     OGLVertexArray attributeless_vao;
     OGLBuffer d24s8_abgr_buffer;
     GLsizeiptr d24s8_abgr_buffer_size;
-    OGLShader d24s8_abgr_shader;
+    OGLProgram d24s8_abgr_shader;
     GLint d24s8_abgr_tbo_size_u_id;
     GLint d24s8_abgr_viewport_u_id;
 };

src/video_core/renderer_opengl/gl_resource_manager.h

@@ -5,6 +5,7 @@
 #pragma once
 
 #include <utility>
+#include <vector>
 #include <glad/glad.h>
 #include "common/common_types.h"
 #include "video_core/renderer_opengl/gl_shader_util.h"
@@ -96,11 +97,53 @@ public:
         return *this;
     }
 
-    /// Creates a new internal OpenGL resource and stores the handle
+    void Create(const char* source, GLenum type) {
-    void Create(const char* vert_shader, const char* frag_shader) {
         if (handle != 0)
             return;
-        handle = GLShader::LoadProgram(vert_shader, frag_shader);
+        if (source == nullptr)
+            return;
+        handle = GLShader::LoadShader(source, type);
+    }
+
+    void Release() {
+        if (handle == 0)
+            return;
+        glDeleteShader(handle);
+        handle = 0;
+    }
+
+    GLuint handle = 0;
+};
+
+class OGLProgram : private NonCopyable {
+public:
+    OGLProgram() = default;
+
+    OGLProgram(OGLProgram&& o) : handle(std::exchange(o.handle, 0)) {}
+
+    ~OGLProgram() {
+        Release();
+    }
+
+    OGLProgram& operator=(OGLProgram&& o) {
+        Release();
+        handle = std::exchange(o.handle, 0);
+        return *this;
+    }
+
+    /// Creates a new program from given shader objects
+    void Create(bool separable_program, const std::vector<GLuint>& shaders) {
+        if (handle != 0)
+            return;
+        handle = GLShader::LoadProgram(separable_program, shaders);
+    }
+
+    /// Creates a new program from given shader soruce code
+    void Create(const char* vert_shader, const char* frag_shader) {
+        OGLShader vert, frag;
+        vert.Create(vert_shader, GL_VERTEX_SHADER);
+        frag.Create(frag_shader, GL_FRAGMENT_SHADER);
+        Create(false, {vert.handle, frag.handle});
     }
 
     /// Deletes the internal OpenGL resource
@@ -115,6 +158,38 @@ public:
     GLuint handle = 0;
 };
 
+class OGLPipeline : private NonCopyable {
+public:
+    OGLPipeline() = default;
+    OGLPipeline(OGLPipeline&& o) {
+        handle = std::exchange<GLuint>(o.handle, 0);
+    }
+    ~OGLPipeline() {
+        Release();
+    }
+    OGLPipeline& operator=(OGLPipeline&& o) {
+        Release();
+        handle = std::exchange<GLuint>(o.handle, 0);
+        return *this;
+    }
+
+    void Create() {
+        if (handle != 0)
+            return;
+        glGenProgramPipelines(1, &handle);
+    }
+
+    void Release() {
+        if (handle == 0)
+            return;
+        glDeleteProgramPipelines(1, &handle);
+        OpenGLState::GetCurState().ResetPipeline(handle).Apply();
+        handle = 0;
+    }
+
+    GLuint handle = 0;
+};
+
 class OGLBuffer : private NonCopyable {
 public:
     OGLBuffer() = default;

src/video_core/renderer_opengl/gl_shader_gen.cpp

@@ -61,6 +61,37 @@ layout (std140) uniform shader_data {
 };
 )";
 
+static std::string GetVertexInterfaceDeclaration(bool is_output, bool separable_shader) {
+    std::string out;
+
+    auto append_variable = [&](const char* var, int location) {
+        if (separable_shader) {
+            out += "layout (location=" + std::to_string(location) + ") ";
+        }
+        out += std::string(is_output ? "out " : "in ") + var + ";\n";
+    };
+
+    append_variable("vec4 primary_color", ATTRIBUTE_COLOR);
+    append_variable("vec2 texcoord0", ATTRIBUTE_TEXCOORD0);
+    append_variable("vec2 texcoord1", ATTRIBUTE_TEXCOORD1);
+    append_variable("vec2 texcoord2", ATTRIBUTE_TEXCOORD2);
+    append_variable("float texcoord0_w", ATTRIBUTE_TEXCOORD0_W);
+    append_variable("vec4 normquat", ATTRIBUTE_NORMQUAT);
+    append_variable("vec3 view", ATTRIBUTE_VIEW);
+
+    if (is_output && separable_shader) {
+        // gl_PerVertex redeclaration is required for separate shader object
+        out += R"(
+out gl_PerVertex {
+    vec4 gl_Position;
+    float gl_ClipDistance[2];
+};
+)";
+    }
+
+    return out;
+}
+
 PicaShaderConfig PicaShaderConfig::BuildFromRegs(const Pica::Regs& regs) {
     PicaShaderConfig res;
 
@@ -206,11 +237,11 @@ static std::string SampleTexture(const PicaShaderConfig& config, unsigned textur
         // Only unit 0 respects the texturing type
         switch (state.texture0_type) {
         case TexturingRegs::TextureConfig::Texture2D:
-            return "texture(tex[0], texcoord[0])";
+            return "texture(tex0, texcoord0)";
         case TexturingRegs::TextureConfig::Projection2D:
-            return "textureProj(tex[0], vec3(texcoord[0], texcoord0_w))";
+            return "textureProj(tex0, vec3(texcoord0, texcoord0_w))";
         case TexturingRegs::TextureConfig::TextureCube:
-            return "texture(tex_cube, vec3(texcoord[0], texcoord0_w))";
+            return "texture(tex_cube, vec3(texcoord0, texcoord0_w))";
         case TexturingRegs::TextureConfig::Shadow2D:
         case TexturingRegs::TextureConfig::ShadowCube:
             NGLOG_CRITICAL(HW_GPU, "Unhandled shadow texture");
@@ -220,15 +251,15 @@ static std::string SampleTexture(const PicaShaderConfig& config, unsigned textur
             LOG_CRITICAL(HW_GPU, "Unhandled texture type %x",
                          static_cast<int>(state.texture0_type));
             UNIMPLEMENTED();
-            return "texture(tex[0], texcoord[0])";
+            return "texture(tex0, texcoord0)";
         }
     case 1:
-        return "texture(tex[1], texcoord[1])";
+        return "texture(tex1, texcoord1)";
     case 2:
         if (state.texture2_use_coord1)
-            return "texture(tex[2], texcoord[1])";
+            return "texture(tex2, texcoord1)";
         else
-            return "texture(tex[2], texcoord[2])";
+            return "texture(tex2, texcoord2)";
     case 3:
         if (state.proctex.enable) {
             return "ProcTex()";
@@ -1020,7 +1051,12 @@ float ProcTexNoiseCoef(vec2 x) {
     }
 
     out += "vec4 ProcTex() {\n";
-    out += "vec2 uv = abs(texcoord[" + std::to_string(config.state.proctex.coord) + "]);\n";
+    if (config.state.proctex.coord < 3) {
+        out += "vec2 uv = abs(texcoord" + std::to_string(config.state.proctex.coord) + ");\n";
+    } else {
+        NGLOG_CRITICAL(Render_OpenGL, "Unexpected proctex.coord >= 3");
+        out += "vec2 uv = abs(texcoord0);\n";
+    }
 
     // Get shift offset before noise generation
     out += "float u_shift = ";
@@ -1085,23 +1121,24 @@ float ProcTexNoiseCoef(vec2 x) {
     }
 }
 
-std::string GenerateFragmentShader(const PicaShaderConfig& config) {
+std::string GenerateFragmentShader(const PicaShaderConfig& config, bool separable_shader) {
     const auto& state = config.state;
 
-    std::string out = R"(
+    std::string out = "#version 330 core\n";
-#version 330 core
+    if (separable_shader) {
+        out += "#extension GL_ARB_separate_shader_objects : enable\n";
+    }
 
-in vec4 primary_color;
+    out += GetVertexInterfaceDeclaration(false, separable_shader);
-in vec2 texcoord[3];
-in float texcoord0_w;
-in vec4 normquat;
-in vec3 view;
 
+    out += R"(
 in vec4 gl_FragCoord;
 
 out vec4 color;
 
-uniform sampler2D tex[3];
+uniform sampler2D tex0;
+uniform sampler2D tex1;
+uniform sampler2D tex2;
 uniform samplerCube tex_cube;
 uniform samplerBuffer lighting_lut;
 uniform samplerBuffer fog_lut;
@@ -1246,8 +1283,11 @@ vec4 secondary_fragment_color = vec4(0.0);
     return out;
 }
 
-std::string GenerateVertexShader() {
+std::string GenerateTrivialVertexShader(bool separable_shader) {
     std::string out = "#version 330 core\n";
+    if (separable_shader) {
+        out += "#extension GL_ARB_separate_shader_objects : enable\n";
+    }
 
     out += "layout(location = " + std::to_string((int)ATTRIBUTE_POSITION) +
            ") in vec4 vert_position;\n";
@@ -1264,14 +1304,7 @@ std::string GenerateVertexShader() {
            ") in vec4 vert_normquat;\n";
     out += "layout(location = " + std::to_string((int)ATTRIBUTE_VIEW) + ") in vec3 vert_view;\n";
 
-    out += R"(
+    out += GetVertexInterfaceDeclaration(true, separable_shader);
-out vec4 primary_color;
-out vec2 texcoord[3];
-out float texcoord0_w;
-out vec4 normquat;
-out vec3 view;
-
-)";
 
     out += UniformBlockDef;
 
@@ -1279,9 +1312,9 @@ out vec3 view;
 
 void main() {
     primary_color = vert_color;
-    texcoord[0] = vert_texcoord0;
+    texcoord0 = vert_texcoord0;
-    texcoord[1] = vert_texcoord1;
+    texcoord1 = vert_texcoord1;
-    texcoord[2] = vert_texcoord2;
+    texcoord2 = vert_texcoord2;
     texcoord0_w = vert_texcoord0_w;
     normquat = vert_normquat;
     view = vert_view;

src/video_core/renderer_opengl/gl_shader_gen.h

@@ -9,7 +9,9 @@
 #include <functional>
 #include <string>
 #include <type_traits>
+#include "common/hash.h"
 #include "video_core/regs.h"
+#include "video_core/shader/shader.h"
 
 namespace GLShader {
 
@@ -132,18 +134,21 @@ struct PicaShaderConfig : Common::HashableStruct<PicaShaderConfigState> {
 };
 
 /**
- * Generates the GLSL vertex shader program source code for the current Pica state
+ * Generates the GLSL vertex shader program source code that accepts vertices from software shader
+ * and directly passes them to the fragment shader.
+ * @param separable_shader generates shader that can be used for separate shader object
  * @returns String of the shader source code
  */
-std::string GenerateVertexShader();
+std::string GenerateTrivialVertexShader(bool separable_shader);
 
 /**
  * Generates the GLSL fragment shader program source code for the current Pica state
  * @param config ShaderCacheKey object generated for the current Pica state, used for the shader
  *               configuration (NOTE: Use state in this struct only, not the Pica registers!)
+ * @param separable_shader generates shader that can be used for separate shader object
  * @returns String of the shader source code
  */
-std::string GenerateFragmentShader(const PicaShaderConfig& config);
+std::string GenerateFragmentShader(const PicaShaderConfig& config, bool separable_shader);
 
 } // namespace GLShader
 

src/video_core/renderer_opengl/gl_shader_manager.cpp

@@ -0,0 +1,216 @@
+// Copyright 2018 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <unordered_map>
+#include <boost/functional/hash.hpp>
+#include <boost/variant.hpp>
+#include "video_core/renderer_opengl/gl_shader_manager.h"
+
+static void SetShaderUniformBlockBinding(GLuint shader, const char* name, UniformBindings binding,
+                                         size_t expected_size) {
+    GLuint ub_index = glGetUniformBlockIndex(shader, name);
+    if (ub_index == GL_INVALID_INDEX) {
+        return;
+    }
+    GLint ub_size = 0;
+    glGetActiveUniformBlockiv(shader, ub_index, GL_UNIFORM_BLOCK_DATA_SIZE, &ub_size);
+    ASSERT_MSG(ub_size == expected_size, "Uniform block size did not match! Got %d, expected %zu",
+               static_cast<int>(ub_size), expected_size);
+    glUniformBlockBinding(shader, ub_index, static_cast<GLuint>(binding));
+}
+
+static void SetShaderUniformBlockBindings(GLuint shader) {
+    SetShaderUniformBlockBinding(shader, "shader_data", UniformBindings::Common,
+                                 sizeof(UniformData));
+}
+
+static void SetShaderSamplerBinding(GLuint shader, const char* name,
+                                    TextureUnits::TextureUnit binding) {
+    GLint uniform_tex = glGetUniformLocation(shader, name);
+    if (uniform_tex != -1) {
+        glUniform1i(uniform_tex, binding.id);
+    }
+}
+
+static void SetShaderSamplerBindings(GLuint shader) {
+    OpenGLState cur_state = OpenGLState::GetCurState();
+    GLuint old_program = std::exchange(cur_state.draw.shader_program, shader);
+    cur_state.Apply();
+
+    // Set the texture samplers to correspond to different texture units
+    SetShaderSamplerBinding(shader, "tex0", TextureUnits::PicaTexture(0));
+    SetShaderSamplerBinding(shader, "tex1", TextureUnits::PicaTexture(1));
+    SetShaderSamplerBinding(shader, "tex2", TextureUnits::PicaTexture(2));
+    SetShaderSamplerBinding(shader, "tex_cube", TextureUnits::TextureCube);
+
+    // Set the texture samplers to correspond to different lookup table texture units
+    SetShaderSamplerBinding(shader, "lighting_lut", TextureUnits::LightingLUT);
+    SetShaderSamplerBinding(shader, "fog_lut", TextureUnits::FogLUT);
+    SetShaderSamplerBinding(shader, "proctex_noise_lut", TextureUnits::ProcTexNoiseLUT);
+    SetShaderSamplerBinding(shader, "proctex_color_map", TextureUnits::ProcTexColorMap);
+    SetShaderSamplerBinding(shader, "proctex_alpha_map", TextureUnits::ProcTexAlphaMap);
+    SetShaderSamplerBinding(shader, "proctex_lut", TextureUnits::ProcTexLUT);
+    SetShaderSamplerBinding(shader, "proctex_diff_lut", TextureUnits::ProcTexDiffLUT);
+
+    cur_state.draw.shader_program = old_program;
+    cur_state.Apply();
+}
+
+/**
+ * An object representing a shader program staging. It can be either a shader object or a program
+ * object, depending on whether separable program is used.
+ */
+class OGLShaderStage {
+public:
+    explicit OGLShaderStage(bool separable) {
+        if (separable) {
+            shader_or_program = OGLProgram();
+        } else {
+            shader_or_program = OGLShader();
+        }
+    }
+
+    void Create(const char* source, GLenum type) {
+        if (shader_or_program.which() == 0) {
+            boost::get<OGLShader>(shader_or_program).Create(source, type);
+        } else {
+            OGLShader shader;
+            shader.Create(source, type);
+            OGLProgram& program = boost::get<OGLProgram>(shader_or_program);
+            program.Create(true, {shader.handle});
+            SetShaderUniformBlockBindings(program.handle);
+            SetShaderSamplerBindings(program.handle);
+        }
+    }
+
+    GLuint GetHandle() const {
+        if (shader_or_program.which() == 0) {
+            return boost::get<OGLShader>(shader_or_program).handle;
+        } else {
+            return boost::get<OGLProgram>(shader_or_program).handle;
+        }
+    }
+
+private:
+    boost::variant<OGLShader, OGLProgram> shader_or_program;
+};
+
+class TrivialVertexShader {
+public:
+    explicit TrivialVertexShader(bool separable) : program(separable) {
+        program.Create(GLShader::GenerateTrivialVertexShader(separable).c_str(), GL_VERTEX_SHADER);
+    }
+    GLuint Get() const {
+        return program.GetHandle();
+    }
+
+private:
+    OGLShaderStage program;
+};
+
+template <typename KeyConfigType, std::string (*CodeGenerator)(const KeyConfigType&, bool),
+          GLenum ShaderType>
+class ShaderCache {
+public:
+    explicit ShaderCache(bool separable) : separable(separable) {}
+    GLuint Get(const KeyConfigType& config) {
+        auto [iter, new_shader] = shaders.emplace(config, OGLShaderStage{separable});
+        OGLShaderStage& cached_shader = iter->second;
+        if (new_shader) {
+            cached_shader.Create(CodeGenerator(config, separable).c_str(), ShaderType);
+        }
+        return cached_shader.GetHandle();
+    }
+
+private:
+    bool separable;
+    std::unordered_map<KeyConfigType, OGLShaderStage> shaders;
+};
+
+using FragmentShaders =
+    ShaderCache<GLShader::PicaShaderConfig, &GLShader::GenerateFragmentShader, GL_FRAGMENT_SHADER>;
+
+class ShaderProgramManager::Impl {
+public:
+    explicit Impl(bool separable)
+        : separable(separable), trivial_vertex_shader(separable), fragment_shaders(separable) {
+        if (separable)
+            pipeline.Create();
+    }
+
+    struct ShaderTuple {
+        GLuint vs = 0;
+        GLuint gs = 0;
+        GLuint fs = 0;
+
+        bool operator==(const ShaderTuple& rhs) const {
+            return std::tie(vs, gs, fs) == std::tie(rhs.vs, rhs.gs, rhs.fs);
+        }
+
+        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;
+
+    TrivialVertexShader trivial_vertex_shader;
+
+    FragmentShaders fragment_shaders;
+
+    bool separable;
+    std::unordered_map<ShaderTuple, OGLProgram, ShaderTuple::Hash> program_cache;
+    OGLPipeline pipeline;
+};
+
+ShaderProgramManager::ShaderProgramManager(bool separable)
+    : impl(std::make_unique<Impl>(separable)) {}
+
+ShaderProgramManager::~ShaderProgramManager() = default;
+
+void ShaderProgramManager::UseTrivialVertexShader() {
+    impl->current.vs = impl->trivial_vertex_shader.Get();
+}
+
+void ShaderProgramManager::UseTrivialGeometryShader() {
+    impl->current.gs = 0;
+}
+
+void ShaderProgramManager::UseFragmentShader(const GLShader::PicaShaderConfig& config) {
+    impl->current.fs = impl->fragment_shaders.Get(config);
+}
+
+void ShaderProgramManager::ApplyTo(OpenGLState& state) {
+    if (impl->separable) {
+        // Without this reseting, AMD sometimes freezes when one stage is changed but not for the
+        // others
+        glUseProgramStages(impl->pipeline.handle,
+                           GL_VERTEX_SHADER_BIT | GL_GEOMETRY_SHADER_BIT | GL_FRAGMENT_SHADER_BIT,
+                           0);
+
+        glUseProgramStages(impl->pipeline.handle, GL_VERTEX_SHADER_BIT, impl->current.vs);
+        glUseProgramStages(impl->pipeline.handle, GL_GEOMETRY_SHADER_BIT, impl->current.gs);
+        glUseProgramStages(impl->pipeline.handle, GL_FRAGMENT_SHADER_BIT, impl->current.fs);
+        state.draw.shader_program = 0;
+        state.draw.program_pipeline = impl->pipeline.handle;
+    } else {
+        OGLProgram& cached_program = impl->program_cache[impl->current];
+        if (cached_program.handle == 0) {
+            cached_program.Create(false, {impl->current.vs, impl->current.gs, impl->current.fs});
+            SetShaderUniformBlockBindings(cached_program.handle);
+            SetShaderSamplerBindings(cached_program.handle);
+        }
+        state.draw.shader_program = cached_program.handle;
+    }
+}

src/video_core/renderer_opengl/gl_shader_manager.h

@@ -0,0 +1,73 @@
+// Copyright 2018 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <memory>
+#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/pica_to_gl.h"
+
+enum class UniformBindings : GLuint { Common };
+
+struct LightSrc {
+    alignas(16) GLvec3 specular_0;
+    alignas(16) GLvec3 specular_1;
+    alignas(16) GLvec3 diffuse;
+    alignas(16) GLvec3 ambient;
+    alignas(16) GLvec3 position;
+    alignas(16) GLvec3 spot_direction; // negated
+    GLfloat dist_atten_bias;
+    GLfloat dist_atten_scale;
+};
+
+/// 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 UniformData {
+    GLint framebuffer_scale;
+    GLint alphatest_ref;
+    GLfloat depth_scale;
+    GLfloat depth_offset;
+    GLint scissor_x1;
+    GLint scissor_y1;
+    GLint scissor_x2;
+    GLint scissor_y2;
+    alignas(16) GLvec3 fog_color;
+    alignas(8) GLvec2 proctex_noise_f;
+    alignas(8) GLvec2 proctex_noise_a;
+    alignas(8) GLvec2 proctex_noise_p;
+    alignas(16) GLvec3 lighting_global_ambient;
+    LightSrc light_src[8];
+    alignas(16) GLvec4 const_color[6]; // A vec4 color for each of the six tev stages
+    alignas(16) GLvec4 tev_combiner_buffer_color;
+    alignas(16) GLvec4 clip_coef;
+};
+
+static_assert(
+    sizeof(UniformData) == 0x460,
+    "The size of the UniformData structure has changed, update the structure in the shader");
+static_assert(sizeof(UniformData) < 16384,
+              "UniformData structure must be less than 16kb as per the OpenGL spec");
+
+/// A class that manage different shader stages and configures them with given config data.
+class ShaderProgramManager {
+public:
+    explicit ShaderProgramManager(bool separable);
+    ~ShaderProgramManager();
+
+    void UseTrivialVertexShader();
+
+    void UseTrivialGeometryShader();
+
+    void UseFragmentShader(const GLShader::PicaShaderConfig& config);
+
+    void ApplyTo(OpenGLState& state);
+
+private:
+    class Impl;
+    std::unique_ptr<Impl> impl;
+};

src/video_core/renderer_opengl/gl_shader_util.cpp

@@ -10,66 +10,67 @@
 
 namespace GLShader {
 
-GLuint LoadProgram(const char* vertex_shader, const char* fragment_shader) {
+GLuint LoadShader(const char* source, GLenum type) {
+    const char* debug_type;
+    switch (type) {
+    case GL_VERTEX_SHADER:
+        debug_type = "vertex";
+        break;
+    case GL_GEOMETRY_SHADER:
+        debug_type = "geometry";
+        break;
+    case GL_FRAGMENT_SHADER:
+        debug_type = "fragment";
+        break;
+    default:
+        UNREACHABLE();
+    }
 
-    // Create the shaders
+    GLuint shader_id = glCreateShader(type);
-    GLuint vertex_shader_id = glCreateShader(GL_VERTEX_SHADER);
+    glShaderSource(shader_id, 1, &source, nullptr);
-    GLuint fragment_shader_id = glCreateShader(GL_FRAGMENT_SHADER);
+    NGLOG_DEBUG(Render_OpenGL, "Compiling {} shader...", debug_type);
+    glCompileShader(shader_id);
 
     GLint result = GL_FALSE;
-    int info_log_length;
+    GLint info_log_length;
-
+    glGetShaderiv(shader_id, GL_COMPILE_STATUS, &result);
-    // Compile Vertex Shader
+    glGetShaderiv(shader_id, GL_INFO_LOG_LENGTH, &info_log_length);
-    LOG_DEBUG(Render_OpenGL, "Compiling vertex shader...");
-
-    glShaderSource(vertex_shader_id, 1, &vertex_shader, nullptr);
-    glCompileShader(vertex_shader_id);
-
-    // Check Vertex Shader
-    glGetShaderiv(vertex_shader_id, GL_COMPILE_STATUS, &result);
-    glGetShaderiv(vertex_shader_id, GL_INFO_LOG_LENGTH, &info_log_length);
 
     if (info_log_length > 1) {
-        std::vector<char> vertex_shader_error(info_log_length);
+        std::vector<char> shader_error(info_log_length);
-        glGetShaderInfoLog(vertex_shader_id, info_log_length, nullptr, &vertex_shader_error[0]);
+        glGetShaderInfoLog(shader_id, info_log_length, nullptr, &shader_error[0]);
         if (result == GL_TRUE) {
-            LOG_DEBUG(Render_OpenGL, "%s", &vertex_shader_error[0]);
+            NGLOG_DEBUG(Render_OpenGL, "{}", &shader_error[0]);
         } else {
-            LOG_ERROR(Render_OpenGL, "Error compiling vertex shader:\n%s", &vertex_shader_error[0]);
+            NGLOG_ERROR(Render_OpenGL, "Error compiling {} shader:\n{}", debug_type,
+                        &shader_error[0]);
+            NGLOG_ERROR(Render_OpenGL, "Shader source code:\n{}", source);
         }
     }
-
+    return shader_id;
-    // Compile Fragment Shader
-    LOG_DEBUG(Render_OpenGL, "Compiling fragment shader...");
-
-    glShaderSource(fragment_shader_id, 1, &fragment_shader, nullptr);
-    glCompileShader(fragment_shader_id);
-
-    // Check Fragment Shader
-    glGetShaderiv(fragment_shader_id, GL_COMPILE_STATUS, &result);
-    glGetShaderiv(fragment_shader_id, GL_INFO_LOG_LENGTH, &info_log_length);
-
-    if (info_log_length > 1) {
-        std::vector<char> fragment_shader_error(info_log_length);
-        glGetShaderInfoLog(fragment_shader_id, info_log_length, nullptr, &fragment_shader_error[0]);
-        if (result == GL_TRUE) {
-            LOG_DEBUG(Render_OpenGL, "%s", &fragment_shader_error[0]);
-        } else {
-            LOG_ERROR(Render_OpenGL, "Error compiling fragment shader:\n%s",
-                      &fragment_shader_error[0]);
-        }
 }
 
+GLuint LoadProgram(bool separable_program, const std::vector<GLuint>& shaders) {
     // Link the program
-    LOG_DEBUG(Render_OpenGL, "Linking program...");
+    NGLOG_DEBUG(Render_OpenGL, "Linking program...");
 
     GLuint program_id = glCreateProgram();
-    glAttachShader(program_id, vertex_shader_id);
+
-    glAttachShader(program_id, fragment_shader_id);
+    for (GLuint shader : shaders) {
+        if (shader != 0) {
+            glAttachShader(program_id, shader);
+        }
+    }
+
+    if (separable_program) {
+        glProgramParameteri(program_id, GL_PROGRAM_SEPARABLE, GL_TRUE);
+    }
 
     glLinkProgram(program_id);
 
     // Check the program
+    GLint result = GL_FALSE;
+    GLint info_log_length;
     glGetProgramiv(program_id, GL_LINK_STATUS, &result);
     glGetProgramiv(program_id, GL_INFO_LOG_LENGTH, &info_log_length);
 
@@ -77,21 +78,19 @@ GLuint LoadProgram(const char* vertex_shader, const char* fragment_shader) {
         std::vector<char> program_error(info_log_length);
         glGetProgramInfoLog(program_id, info_log_length, nullptr, &program_error[0]);
         if (result == GL_TRUE) {
-            LOG_DEBUG(Render_OpenGL, "%s", &program_error[0]);
+            NGLOG_DEBUG(Render_OpenGL, "{}", &program_error[0]);
         } else {
-            LOG_ERROR(Render_OpenGL, "Error linking shader:\n%s", &program_error[0]);
+            NGLOG_ERROR(Render_OpenGL, "Error linking shader:\n{}", &program_error[0]);
         }
     }
 
-    // If the program linking failed at least one of the shaders was probably bad
-    if (result == GL_FALSE) {
-        LOG_ERROR(Render_OpenGL, "Vertex shader:\n%s", vertex_shader);
-        LOG_ERROR(Render_OpenGL, "Fragment shader:\n%s", fragment_shader);
-    }
     ASSERT_MSG(result == GL_TRUE, "Shader not linked");
 
-    glDeleteShader(vertex_shader_id);
+    for (GLuint shader : shaders) {
-    glDeleteShader(fragment_shader_id);
+        if (shader != 0) {
+            glDetachShader(program_id, shader);
+        }
+    }
 
     return program_id;
 }

src/video_core/renderer_opengl/gl_shader_util.h

@@ -4,16 +4,24 @@
 
 #pragma once
 
+#include <vector>
 #include <glad/glad.h>
 
 namespace GLShader {
 
 /**
- * Utility function to create and compile an OpenGL GLSL shader program (vertex + fragment shader)
+ * Utility function to create and compile an OpenGL GLSL shader
- * @param vertex_shader String of the GLSL vertex shader program
+ * @param source String of the GLSL shader program
- * @param fragment_shader String of the GLSL fragment shader program
+ * @param type Type of the shader (GL_VERTEX_SHADER, GL_GEOMETRY_SHADER or GL_FRAGMENT_SHADER)
- * @returns Handle of the newly created OpenGL shader object
  */
-GLuint LoadProgram(const char* vertex_shader, const char* fragment_shader);
+GLuint LoadShader(const char* source, GLenum type);
+
+/**
+ * Utility function to create and link an OpenGL GLSL shader program
+ * @param separable_program whether to create a separable program
+ * @param shaders ID of shaders to attach to the program
+ * @returns Handle of the newly created OpenGL program object
+ */
+GLuint LoadProgram(bool separable_program, const std::vector<GLuint>& shaders);
 
 } // namespace GLShader

src/video_core/renderer_opengl/gl_state.cpp

@@ -71,6 +71,7 @@ OpenGLState::OpenGLState() {
     draw.vertex_buffer = 0;
     draw.uniform_buffer = 0;
     draw.shader_program = 0;
+    draw.program_pipeline = 0;
 
     scissor.enabled = false;
     scissor.x = 0;
@@ -282,6 +283,11 @@ void OpenGLState::Apply() const {
         glUseProgram(draw.shader_program);
     }
 
+    // Program pipeline
+    if (draw.program_pipeline != cur_state.draw.program_pipeline) {
+        glBindProgramPipeline(draw.program_pipeline);
+    }
+
     // Scissor test
     if (scissor.enabled != cur_state.scissor.enabled) {
         if (scissor.enabled) {
@@ -360,6 +366,13 @@ OpenGLState& OpenGLState::ResetProgram(GLuint handle) {
     return *this;
 }
 
+OpenGLState& OpenGLState::ResetPipeline(GLuint handle) {
+    if (draw.program_pipeline == handle) {
+        draw.program_pipeline = 0;
+    }
+    return *this;
+}
+
 OpenGLState& OpenGLState::ResetBuffer(GLuint handle) {
     if (draw.vertex_buffer == handle) {
         draw.vertex_buffer = 0;

src/video_core/renderer_opengl/gl_state.h

@@ -128,6 +128,7 @@ public:
         GLuint vertex_buffer;    // GL_ARRAY_BUFFER_BINDING
         GLuint uniform_buffer;   // GL_UNIFORM_BUFFER_BINDING
         GLuint shader_program;   // GL_CURRENT_PROGRAM
+        GLuint program_pipeline; // GL_PROGRAM_PIPELINE_BINDING
     } draw;
 
     struct {
@@ -161,6 +162,7 @@ public:
     OpenGLState& ResetTexture(GLuint handle);
     OpenGLState& ResetSampler(GLuint handle);
     OpenGLState& ResetProgram(GLuint handle);
+    OpenGLState& ResetPipeline(GLuint handle);
     OpenGLState& ResetBuffer(GLuint handle);
     OpenGLState& ResetVertexArray(GLuint handle);
     OpenGLState& ResetFramebuffer(GLuint handle);

src/video_core/renderer_opengl/renderer_opengl.h

@@ -73,7 +73,7 @@ private:
     // OpenGL object IDs
     OGLVertexArray vertex_array;
     OGLBuffer vertex_buffer;
-    OGLShader shader;
+    OGLProgram shader;
 
     /// Display information for top and bottom screens respectively
     std::array<ScreenInfo, 2> screen_infos;