OpenGL: Added option to control desired adapter type in OpenGL (close #…

…450)
DiligentGraphics · Jan 10, 2024 · c7425fd · c7425fd
1 parent 1210c85
commit c7425fd
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Showing 4 changed files with 53 additions and 0 deletions.
diff --git a/Graphics/GraphicsEngine/interface/GraphicsTypes.h b/Graphics/GraphicsEngine/interface/GraphicsTypes.h
@@ -3485,6 +3485,12 @@ struct EngineGLCreateInfo DILIGENT_DERIVE(EngineCreateInfo)
     /// Use IRenderDevice::GetDeviceInfo().NDC to get current NDC.
     Bool         ZeroToOneNDZ DEFAULT_INITIALIZER(false);
 
+    /// The GPU preference allows you to request either the integrated or dedicated GPU
+    /// on systems having both onboard and dedicated GPUs. Currently this works only on Windows and Linux
+    /// - On Windows this is done by setting the `NvOptimusEnablement` and  `AmdPowerXpressRequestHighPerformance` 
+    /// - On Linux this affects the `DRI_PRIME` environment variable that's used by Mesa drivers that support PRIME.
+    ADAPTER_TYPE PreferredAdapterType DEFAULT_INITIALIZER(ADAPTER_TYPE_UNKNOWN);
+
 #if PLATFORM_EMSCRIPTEN
     /// WebGL context attributes.
     WebGLContextAttribs WebGLAttribs;

diff --git a/Graphics/GraphicsEngineOpenGL/CMakeLists.txt b/Graphics/GraphicsEngineOpenGL/CMakeLists.txt
@@ -303,7 +303,11 @@ set_source_files_properties(
     readme.md PROPERTIES HEADER_FILE_ONLY TRUE
 )
 
+add_library(Diligent-GLAdapterSelector OBJECT "src/GLAdapterSelector.cpp")
+set_target_properties(Diligent-GLAdapterSelector PROPERTIES FOLDER DiligentCore/Graphics)
+
 if(DILIGENT_INSTALL_CORE)
     install_core_lib(Diligent-GraphicsEngineOpenGL-shared)
     install_core_lib(Diligent-GraphicsEngineOpenGL-static)
+    install_core_lib(Diligent-GLAdapterSelector)
 endif()
diff --git a/Graphics/GraphicsEngineOpenGL/src/EngineFactoryOpenGL.cpp b/Graphics/GraphicsEngineOpenGL/src/EngineFactoryOpenGL.cpp
@@ -137,6 +137,28 @@ static void SetDefaultGraphicsAdapterInfo(GraphicsAdapterInfo& AdapterInfo)
     AdapterInfo.Queues[0].TextureCopyGranularity[2] = 1;
 }
 
+static void SetPreferredAdapter(const EngineGLCreateInfo& EngineCI)
+{
+    bool IsEnableDedicatedGPU = EngineCI.PreferredAdapterType == ADAPTER_TYPE_DISCRETE;
+#if PLATFORM_WIN32 || PLATFORM_UNIVERSAL_WINDOWS
+    const HMODULE ModuleHandle                         = GetModuleHandle(nullptr);
+    Uint64* const NvOptimusEnablement                  = reinterpret_cast<Uint64*>(GetProcAddress(ModuleHandle, "NvOptimusEnablement"));
+    Uint64* const AmdPowerXpressRequestHighPerformance = reinterpret_cast<Uint64*>(GetProcAddress(ModuleHandle, "AmdPowerXpressRequestHighPerformance"));
+    if (!NvOptimusEnablement && !AmdPowerXpressRequestHighPerformance)
+        LOG_WARNING_MESSAGE("Nither NvOptimusEnablement nor AmdPowerXpressRequestHighPerformance symbols found");
+    if (AmdPowerXpressRequestHighPerformance)
+        *AmdPowerXpressRequestHighPerformance = IsEnableDedicatedGPU;
+    if (NvOptimusEnablement)
+        *NvOptimusEnablement = IsEnableDedicatedGPU;
+#elif PLAtTFORM_LINUX
+    setenv("DRI_PRIME", IsEnableDedicatedGPU ? "1" : "0", 1);
+#else
+    (void)IsEnableDedicatedGPU;
+    if (EngineCI.PreferredAdapterType != ADAPTER_TYPE_UNKNOWN)
+        LOG_WARNING_MESSAGE("Setting preferred adapter type isn't supported on this platform");
+#endif
+}
+
 void EngineFactoryOpenGLImpl::EnumerateAdapters(Version              MinVersion,
                                                 Uint32&              NumAdapters,
                                                 GraphicsAdapterInfo* Adapters) const
@@ -205,6 +227,7 @@ void EngineFactoryOpenGLImpl::CreateDeviceAndSwapChainGL(const EngineGLCreateInf
         SetRawAllocator(EngineCI.pRawMemAllocator);
         auto& RawMemAllocator = GetRawAllocator();
 
+        SetPreferredAdapter(EngineCI);
         RenderDeviceGLImpl* pRenderDeviceOpenGL{
             NEW_RC_OBJ(RawMemAllocator, "TRenderDeviceGLImpl instance", TRenderDeviceGLImpl)(
                 RawMemAllocator, this, EngineCI, &SCDesc //
@@ -303,6 +326,7 @@ void EngineFactoryOpenGLImpl::AttachToActiveGLContext(const EngineGLCreateInfo&
         SetRawAllocator(EngineCI.pRawMemAllocator);
         auto& RawMemAllocator = GetRawAllocator();
 
+        SetPreferredAdapter(EngineCI);
         RenderDeviceGLImpl* pRenderDeviceOpenGL{
             NEW_RC_OBJ(RawMemAllocator, "TRenderDeviceGLImpl instance", TRenderDeviceGLImpl)(
                 RawMemAllocator, this, EngineCI //

diff --git a/Graphics/GraphicsEngineOpenGL/src/GLAdapterSelector.cpp b/Graphics/GraphicsEngineOpenGL/src/GLAdapterSelector.cpp
@@ -0,0 +1,19 @@
+#include <cinttypes>
+
+#if PLATFORM_WIN32 || PLATFORM_UNIVERSAL_WINDOWS
+#    define DILIGENT_INTERFACE_EXPORT __declspec(dllexport)
+#elif PLATFORM_LINUX
+#    define DILIGENT_INTERFACE_EXPORT __attribute__((visibility("default")))
+#else
+#    define DILIGENT_INTERFACE_EXPORT
+#endif
+
+/// Let the NVIDIA and AMD know we want to use their graphics card on a dual graphics card system.
+extern "C"
+{
+    /// https://community.amd.com/thread/169965
+    __declspec(dllexport) uint64_t AmdPowerXpressRequestHighPerformance = 0x0;
+
+    /// http://developer.download.nvidia.com/devzone/devcenter/gamegraphics/files/OptimusRenderingPolicies.pdf
+    __declspec(dllexport) uint64_t NvOptimusEnablement = 0x0;
+}