[Feat] (MG_Util/ShaderCompiler, MG_State/Program): reflect uniform location

MobileGL/MG_State/GLState/ProgramState/ProgramObject.cpp

@@ -63,6 +63,7 @@ namespace MobileGL {
             Vector<SharedPtr<ShaderObject>>& ProgramObject::GetAttachedShaders() {
                 return m_shaders;
             }
+
         } // namespace GLState
     } // namespace MG_State
 } // namespace MobileGL

MobileGL/MG_State/GLState/ProgramState/ShaderObject.cpp

@@ -1,6 +1,8 @@
 #include "ShaderObject.h"
 #include <MG_Util/ShaderTranspiler/ShaderCompiler.h>
 
+#include "MG_Util/ShaderTranspiler/glslang/UniformTraverser.h"
+
 namespace MobileGL {
     namespace MG_State {
         namespace GLState {
@@ -13,6 +15,10 @@ namespace MobileGL {
             }
 
             void ShaderObject::Compile() {
+                if (!DoReflection()) {
+                    return;
+                }
+
                 using namespace MG_Util::ShaderTranspiler;
                 ShaderAttrib attrib{
                     .shaderType = GetGLShaderTypeByMGLShaderStage(m_stage),
@@ -36,6 +42,36 @@ namespace MobileGL {
             void ShaderObject::MarkAsDeleted() {
                 m_deleteStatus = true;
             }
+
+            bool ShaderObject::DoReflection() {
+                using namespace MG_Util::ShaderTranspiler;
+                ShaderAttrib attrib{
+                    .shaderType = GetGLShaderTypeByMGLShaderStage(m_stage),
+                    .sourceStr = m_source,
+                    .flags = ShaderCompileBits::CompileForOpenGL
+                };
+
+                auto result = ShaderCompiler::CompileShader(attrib);
+                if (!result) {
+                    m_compileStatus = false;
+                    m_infoLog = result.error().log;
+
+                    const std::string e = std::format("Shader compilation failed: \nerrc: {}\nmsg: {}\n",
+                                                      result.error().errc, result.error().log);
+                    return false;
+                }
+
+                auto pShader = result.value();
+                auto root = pShader->getIntermediate()->getTreeRoot();
+                UniformTraverser traverser;
+                root->traverse(&traverser);
+                auto& symbols = traverser.GetCollectedSymbols();
+                for (const auto& symbol : symbols) {
+                    m_uniforms[symbol->getName().c_str()] = symbol->getQualifier().layoutLocation;
+                }
+
+                return true;
+            }
         } // namespace GLState
     } // namespace MG_State
 } // namespace MobileGL

MobileGL/MG_State/GLState/ProgramState/ShaderObject.h

@@ -68,12 +68,14 @@ namespace MobileGL {
                 SharedPtr<glslang::TShader> GetCompiledShader() const { return m_shader; }
                 const String& GetInfoLog() const { return m_infoLog; }
             private:
+                bool DoReflection();
                 const Uint m_id = 0;
                 const ShaderStage m_stage;
                 String m_source;
                 SharedPtr<glslang::TShader> m_shader;
-                String m_infoLog;
+                UnorderedMap<String, Int> m_uniforms;
 
+                String m_infoLog;
                 Bool m_deleteStatus = false;
                 Bool m_compileStatus = false;
             };

MobileGL/MG_Test/Buffer/CMakeLists.txt

@@ -36,6 +36,7 @@ add_executable(
         ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/SpvcSession.cpp
         ${MGL_ROOT}/MobileGL/MG_Backend/Init.cpp
         ${MGL_ROOT}/MobileGL/MG_Util/Debug/Log.cpp
+        ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/glslang/UniformTraverser.cpp
 )
 
 target_include_directories(BufferTest PRIVATE

MobileGL/MG_Test/Program/CMakeLists.txt

@@ -8,6 +8,7 @@ add_executable(
         ${MGL_ROOT}/MobileGL/MG_Util/Converters/GLToGlslang/GLShaderLangConverter.cpp
         ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/ShaderCompiler.cpp
         ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/SpvcSession.cpp
+        ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/glslang/UniformTraverser.cpp
 )
 
 target_include_directories(ProgramUtilTest PRIVATE
@@ -35,6 +36,8 @@ add_executable(
         ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/ShaderCompiler.cpp
         ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/SpvcSession.cpp
 
+        ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/glslang/UniformTraverser.cpp
+
         ${MGL_ROOT}/MobileGL/MG_State/GLState/Core.cpp
         ${MGL_ROOT}/MobileGL/MG_State/GLState/BufferState/BufferState.cpp
         ${MGL_ROOT}/MobileGL/MG_State/GLState/BufferState/BufferObject.cpp

MobileGL/MG_Test/Program/ProgramUtilTest.cpp

@@ -7,6 +7,8 @@
 #include <MG_Util/Converters/GLToStr/GLEnumConverter.h>
 #include <MG_Util/ShaderTranspiler/ShaderCompiler.h>
 #include <MG_Util/ShaderTranspiler/Types.h>
+
+#include "MG_Util/ShaderTranspiler/glslang/UniformTraverser.h"
 using namespace MobileGL;
 
 class ProgramUtilTest : public ::testing::Test {
@@ -165,6 +167,54 @@ TEST_F(ProgramUtilTest, CompileFragmentShaderWithDiscard) {
     }
 }
 
+const char* vs_location = R"(#version 460
+
+in vec4 Position;
+
+layout(location = 1) uniform mat4 ProjMat;
+layout(location = 20) uniform vec2 InSize;
+layout(location = 0) uniform vec2 OutSize;
+
+out vec2 texCoord;
+out vec2 oneTexel;
+
+void main(){
+    vec4 outPos = ProjMat * vec4(Position.xy, 0.0, 1.0);
+    gl_Position = vec4(outPos.xy, 0.2, 1.0);
+
+    oneTexel = 1.0 / InSize;
+
+    texCoord = Position.xy / OutSize;
+})";
+
+TEST_F(ProgramUtilTest, CompileVertexShaderWithLocation) {
+    using namespace MG_Util::ShaderTranspiler;
+    ShaderAttrib attrib {
+        .shaderType = GL_VERTEX_SHADER,
+        .sourceStr = vs_location,
+        .flags = ShaderCompileBits::CompileForOpenGL
+    };
+    auto res = ShaderCompiler::CompileShader(attrib);
+    if (!res) {
+        ASSERT_NE(res.error().errc, 0);
+        FAIL() << "errc: " << res.error().errc << "\nlog: " << res.error().log;
+    }
+    UnorderedMap<String, Int> uniforms;
+
+    auto pShader = res.value();
+    auto root = pShader->getIntermediate()->getTreeRoot();
+    UniformTraverser traverser;
+    root->traverse(&traverser);
+    auto& symbols = traverser.GetCollectedSymbols();
+    for (const auto& symbol : symbols) {
+        uniforms[symbol->getName().c_str()] = symbol->getQualifier().layoutLocation;
+    }
+
+    EXPECT_EQ(uniforms["ProjMat"], 1);
+    EXPECT_EQ(uniforms["InSize"], 20);
+    EXPECT_EQ(uniforms["OutSize"], 0);
+}
+
 TEST_F(ProgramUtilTest, CompileAndLinkProgram) {
     using namespace MG_Util::ShaderTranspiler;
     ShaderAttrib vs_attrib {

MobileGL/MG_Test/VertexArray/CMakeLists.txt

@@ -36,6 +36,7 @@ add_executable(
         ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/SpvcSession.cpp
         ${MGL_ROOT}/MobileGL/MG_Backend/Init.cpp
         ${MGL_ROOT}/MobileGL/MG_Util/Debug/Log.cpp
+        ${MGL_ROOT}/MobileGL/MG_Util/ShaderTranspiler/glslang/UniformTraverser.cpp
 )
 
 target_include_directories(VertexArrayTest PRIVATE

MobileGL/MG_Util/ShaderTranspiler/glslang/UniformTraverser.cpp

@@ -0,0 +1,39 @@
+//
+// Created by Swung 0x48 on 2025/7/20.
+//
+
+#include "UniformTraverser.h"
+
+namespace MobileGL {
+namespace MG_Util {
+namespace ShaderTranspiler {
+    void UniformTraverser::visitSymbol(glslang::TIntermSymbol *symbol) {
+        auto parent = getParentNode();
+        if (!parent)
+            return;
+        auto parentAgg = parent->getAsAggregate();
+        if (!parentAgg || parentAgg->getOp() != glslang::EOpLinkerObjects)
+            return;
+
+        const auto &type = symbol->getType();
+        if (symbol->getQualifier().isUniform()) {
+            m_collectedSymbols.emplace_back(symbol);
+            // auto& name = symbol->getName();
+            // auto qualifier = symbol->getQualifier();
+            //
+            // printf("layout(location = %d) uniform %s\n", qualifier.layoutLocation, name.c_str());
+            // auto &uniform = uniforms.emplace_back();
+            // uniform.name = name;
+            // uniform.storageQualifier = qualifier.storage;
+            // uniform.layoutLocation = qualifier.layoutLocation;
+            // uniform.layoutBinding = qualifier.layoutBinding;
+            // uniform.layoutPacking = qualifier.layoutPacking;
+        } else if (type.getBasicType() == glslang::EbtSampler) {
+            // auto &uniform = samplers.emplace_back();
+            // uniform.name = symbol->getName();
+            // uniform.sampler = type.getSampler();
+        }
+    }
+}
+}
+}

MobileGL/MG_Util/ShaderTranspiler/glslang/UniformTraverser.h

@@ -0,0 +1,24 @@
+//
+// Created by Swung 0x48 on 2025/7/20.
+//
+
+#ifndef MOBILEGL_UNIFORMTRAVERSER_H
+#define MOBILEGL_UNIFORMTRAVERSER_H
+
+#include "Includes.h"
+
+namespace MobileGL {
+namespace MG_Util {
+namespace ShaderTranspiler {
+    class UniformTraverser : public glslang::TIntermTraverser {
+    public:
+        void visitSymbol(glslang::TIntermSymbol *symbol) override;
+        Vector<glslang::TIntermSymbol*>& GetCollectedSymbols() { return m_collectedSymbols; }
+    private:
+        Vector<glslang::TIntermSymbol*> m_collectedSymbols;
+    };
+}
+}
+}
+
+#endif //MOBILEGL_UNIFORMTRAVERSER_H