5 files changed, 65 insertions, 2 deletions

diff --git a/src/video_core/CMakeLists.txt b/src/video_core/CMakeLists.txt
index 242a0d1cd..804395d38 100644
--- a/src/video_core/CMakeLists.txt
+++ b/src/video_core/CMakeLists.txt
@@ -1,4 +1,6 @@
 add_library(video_core STATIC
+    const_buffer_accessor.cpp
+    const_buffer_accessor.h
     dma_pusher.cpp
     dma_pusher.h
     debug_utils/debug_utils.cpp
diff --git a/src/video_core/const_buffer_accessor.cpp b/src/video_core/const_buffer_accessor.cpp
new file mode 100644
index 000000000..c89ab91c7
--- /dev/null
+++ b/src/video_core/const_buffer_accessor.cpp
@@ -0,0 +1,35 @@
+#pragma once
+
+#include <cstring>
+
+#include "common/common_types.h"
+#include "core/core.h"
+#include "core/memory.h"
+#include "video_core/const_buffer_accessor.h"
+#include "video_core/engines/maxwell_3d.h"
+#include "video_core/gpu.h"
+#include "video_core/memory_manager.h"
+
+namespace Tegra {
+
+u32 ConstBufferAccessor::access32(Tegra::Engines::Maxwell3D::Regs::ShaderStage stage,
+                                  u64 const_buffer, u64 offset) {
+    auto& memory_manager = Core::System::GetInstance().GPU().MemoryManager();
+    const auto& shader_stage = maxwell3d.state.shader_stages[static_cast<std::size_t>(stage)];
+    const auto& buffer = shader_stage.const_buffers[const_buffer];
+    u32 result;
+    std::memcpy(&result, memory_manager.GetPointer(buffer.address + offset * 4), sizeof(u32));
+    return result;
+}
+
+u64 ConstBufferAccessor::access64(Tegra::Engines::Maxwell3D::Regs::ShaderStage stage,
+                                  u64 const_buffer, u64 offset) {
+    auto& memory_manager = Core::System::GetInstance().GPU().MemoryManager();
+    const auto& shader_stage = maxwell3d.state.shader_stages[static_cast<std::size_t>(stage)];
+    const auto& buffer = shader_stage.const_buffers[const_buffer];
+    u64 result;
+    std::memcpy(&result, memory_manager.GetPointer(buffer.address + offset * 4), sizeof(u64));
+    return result;
+}
+
+} // namespace Tegra
diff --git a/src/video_core/const_buffer_accessor.h b/src/video_core/const_buffer_accessor.h
new file mode 100644
index 000000000..2410f1483
--- /dev/null
+++ b/src/video_core/const_buffer_accessor.h
@@ -0,0 +1,21 @@
+#pragma once
+
+#include "common/common_types.h"
+#include "video_core/engines/maxwell_3d.h"
+
+namespace Tegra {
+
+class ConstBufferAccessor {
+public:
+    ConstBufferAccessor(Tegra::Engines::Maxwell3D& maxwell3d) : maxwell3d(maxwell3d) {}
+    ~ConstBufferAccessor() = default;
+
+    u32 access32(Tegra::Engines::Maxwell3D::Regs::ShaderStage stage, u64 const_buffer, u64 offset);
+
+    u64 access64(Tegra::Engines::Maxwell3D::Regs::ShaderStage stage, u64 const_buffer, u64 offset);
+
+private:
+    Tegra::Engines::Maxwell3D& maxwell3d;
+};
+
+} // namespace Tegra
diff --git a/src/video_core/renderer_opengl/gl_rasterizer.cpp b/src/video_core/renderer_opengl/gl_rasterizer.cpp
index 7ff1e6737..f2ac5382d 100644
--- a/src/video_core/renderer_opengl/gl_rasterizer.cpp
+++ b/src/video_core/renderer_opengl/gl_rasterizer.cpp
@@ -98,9 +98,11 @@ struct FramebufferCacheKey {
     }
 };
 
-RasterizerOpenGL::RasterizerOpenGL(Core::System& system, ScreenInfo& info)
+RasterizerOpenGL::RasterizerOpenGL(Core::Frontend::EmuWindow& window, Core::System& system,
+                                   ScreenInfo& info)
     : res_cache{*this}, shader_cache{*this, system}, global_cache{*this}, system{system},
-      screen_info{info}, buffer_cache(*this, STREAM_BUFFER_SIZE) {
+      screen_info{info}, buffer_cache(*this, STREAM_BUFFER_SIZE),
+      const_buffer_accessor(system.GPU().Maxwell3D()) {
     // Create sampler objects
     for (std::size_t i = 0; i < texture_samplers.size(); ++i) {
         texture_samplers[i].Create();
diff --git a/src/video_core/renderer_opengl/gl_rasterizer.h b/src/video_core/renderer_opengl/gl_rasterizer.h
index 54fbf48aa..886e9c2b5 100644
--- a/src/video_core/renderer_opengl/gl_rasterizer.h
+++ b/src/video_core/renderer_opengl/gl_rasterizer.h
@@ -17,6 +17,7 @@
 #include <glad/glad.h>
 
 #include "common/common_types.h"
+#include "video_core/const_buffer_accessor.h"
 #include "video_core/engines/maxwell_3d.h"
 #include "video_core/rasterizer_cache.h"
 #include "video_core/rasterizer_interface.h"
@@ -229,6 +230,8 @@ private:
     PrimitiveAssembler primitive_assembler{buffer_cache};
     GLint uniform_buffer_alignment;
 
+    Tegra::ConstBufferAccessor const_buffer_accessor;
+
     std::size_t CalculateVertexArraysSize() const;
 
     std::size_t CalculateIndexBufferSize() const;