From 5b3d5c998a9db47e32c3166ddf13c5e45ced1eb4 Mon Sep 17 00:00:00 2001
From: Swung0x48 <swung0x48@outlook.com>
Date: Mon, 27 Oct 2025 13:17:42 +0800
Subject: [PATCH] [Feat] (MG_State/ProgramObject, MG_State/GL_Program):
 implement sampler unit in program state

---
 .../MG_Impl/GLImpl/Program/GL_Program.cpp     | 15 +++++++++++----
 .../GLState/ProgramState/ProgramObject.cpp    |  1 +
 .../GLState/ProgramState/ProgramObject.h      | 19 +++++++++++++++++--
 3 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp b/MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp
index 182e060a..3cc2bb54 100644
--- a/MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp
+++ b/MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp
@@ -455,10 +455,17 @@ namespace MobileGL {
 
         template <GLsizei VecCount, typename T>
         void Uniform_State(MG_State::GLState::ProgramObject& programObject, GLuint location, T* value) {
-            auto size = programObject.GetUniformSizesInBytes(location);
-            auto offset = programObject.GetUniformOffset(location);
-            assert(size >= VecCount * sizeof(T));
-            memcpy((char*)programObject.MapUBO() + offset, value, VecCount * sizeof(T));
+            if (!programObject.IsUniformOpaqueAtLocation(location)) {
+                auto size = programObject.GetUniformSizesInBytes(location);
+                auto offset = programObject.GetUniformOffset(location);
+                assert(size >= VecCount * sizeof(T));
+                memcpy((char*)programObject.MapUBO() + offset, value, VecCount * sizeof(T));
+            } else {
+                auto* ttype = programObject.GetUniformTType(location);
+                if (ttype->isTexture() || ttype->isImage()) {
+                    programObject.SetUniformSamplerOrImageUnitIndex(location, *value);
+                }
+            }
         }
 
         template <GLsizei VecCount, typename T>
diff --git a/MobileGL/MG_State/GLState/ProgramState/ProgramObject.cpp b/MobileGL/MG_State/GLState/ProgramState/ProgramObject.cpp
index 3b7b0f58..f51eb45a 100644
--- a/MobileGL/MG_State/GLState/ProgramState/ProgramObject.cpp
+++ b/MobileGL/MG_State/GLState/ProgramState/ProgramObject.cpp
@@ -92,6 +92,7 @@ namespace MobileGL {
                 // Be aware, there could be gaps in between these vectors
                 // Locations can be not sequential
                 m_uniformIndexInTProgram.resize(m_maxUniformLocation + 1, 4095);
+                m_uniformSamplerOrImageUnitIndex.resize(m_maxUniformLocation + 1, 0);
 
                 Vector<int> unallocatedUniformIndex;
 
diff --git a/MobileGL/MG_State/GLState/ProgramState/ProgramObject.h b/MobileGL/MG_State/GLState/ProgramState/ProgramObject.h
index bc0c4bde..8dc9118f 100644
--- a/MobileGL/MG_State/GLState/ProgramState/ProgramObject.h
+++ b/MobileGL/MG_State/GLState/ProgramState/ProgramObject.h
@@ -29,14 +29,19 @@ namespace MobileGL {
                         return -1;
                     return (Int)it->second;
                 }
+
                 GLenum GetUniformType(Uint location) const {
                     auto& uniform = m_program->getUniform(m_uniformIndexInTProgram[location]);
                     return uniform.glDefineType;
                 }
 
-                Bool IsUniformOpaqueAtLocation(Uint location) const {
+                const glslang::TType* GetUniformTType(Uint location) const {
                     auto& uniform = m_program->getUniform(m_uniformIndexInTProgram[location]);
-                    return uniform.getType()->isOpaque();
+                    return uniform.getType();
+                }
+
+                Bool IsUniformOpaqueAtLocation(Uint location) const {
+                    return GetUniformTType(location)->isOpaque();
                 }
 
                 const String& GetUniformName(Uint location) const {
@@ -56,6 +61,14 @@ namespace MobileGL {
                 const String& GetAttribName(Uint index) const { return m_attribs[index]; }
                 void* MapUBO() { return m_uboScratch.data(); }
 
+                void SetUniformSamplerOrImageUnitIndex(Uint location, Int unit) {
+                    m_uniformSamplerOrImageUnitIndex[location] = unit;
+                }
+
+                Int SetUniformSamplerOrImageUnitIndex(Uint location) const {
+                    return m_uniformSamplerOrImageUnitIndex[location];
+                }
+
                 Bool GetDeleteStatus() const { return m_deleteStatus; }
                 Bool GetLinkStatus() const { return m_linkStatus; }
                 Bool GetValidateStatus() const { return m_validateStatus; }
@@ -91,6 +104,8 @@ namespace MobileGL {
                 // Ordered by location,
                 // aka. m_uniformIndexInTProgram[loc] == "uniform index of TProgram at location `loc`"
                 Vector<Int> m_uniformIndexInTProgram;
+                // ditto. Will be set at glUniform1i
+                Vector<Int> m_uniformSamplerOrImageUnitIndex;
 
                 // Need to be reflected after linking of SPIR-V binary
                 Vector<Uint> m_uniformOffsets;