Use direct composition for d3d12 backend

drivers/d3d12/rendering_context_driver_d3d12.cpp

@@ -96,6 +96,9 @@ RenderingContextDriverD3D12::~RenderingContextDriverD3D12() {
 	if (lib_dxgi) {
 		FreeLibrary(lib_dxgi);
 	}
+	if (lib_dcomp) {
+		FreeLibrary(lib_dcomp);
+	}
 }
 
 Error RenderingContextDriverD3D12::_init_device_factory() {
@@ -108,6 +111,9 @@ Error RenderingContextDriverD3D12::_init_device_factory() {
 	lib_dxgi = LoadLibraryW(L"DXGI.dll");
 	ERR_FAIL_NULL_V(lib_dxgi, ERR_CANT_CREATE);
 
+	lib_dcomp = LoadLibraryW(L"Dcomp.dll");
+	ERR_FAIL_NULL_V(lib_dcomp, ERR_CANT_CREATE);
+
 	// Note: symbol is not available in MinGW import library.
 	PFN_D3D12_GET_INTERFACE d3d_D3D12GetInterface = (PFN_D3D12_GET_INTERFACE)(void *)GetProcAddress(lib_d3d12, "D3D12GetInterface");
 	if (!d3d_D3D12GetInterface) {

drivers/d3d12/rendering_context_driver_d3d12.h

@@ -59,6 +59,20 @@
 #undef AS
 #endif
 
+#if (WINVER < _WIN32_WINNT_WIN8) && defined(_MSC_VER)
+#pragma push_macro("NTDDI_VERSION")
+#pragma push_macro("WINVER")
+#undef NTDDI_VERSION
+#undef WINVER
+#define NTDDI_VERSION NTDDI_WIN8
+#define WINVER _WIN32_WINNT_WIN8
+#include <dcomp.h>
+#pragma pop_macro("WINVER")
+#pragma pop_macro("NTDDI_VERSION")
+#else
+#include <dcomp.h>
+#endif
+
 #include "d3dx12.h"
 #include <dxgi1_6.h>
 
@@ -114,10 +128,14 @@ class RenderingContextDriverD3D12 : public RenderingContextDriver {
 		uint32_t height = 0;
 		DisplayServer::VSyncMode vsync_mode = DisplayServer::VSYNC_ENABLED;
 		bool needs_resize = false;
+		ComPtr<IDCompositionDevice> composition_device;
+		ComPtr<IDCompositionTarget> composition_target;
+		ComPtr<IDCompositionVisual> composition_visual;
 	};
 
 	HMODULE lib_d3d12 = nullptr;
 	HMODULE lib_dxgi = nullptr;
+	HMODULE lib_dcomp = nullptr;
 
 	IDXGIAdapter1 *create_adapter(uint32_t p_adapter_index) const;
 	ID3D12DeviceFactory *device_factory_get() const;

drivers/d3d12/rendering_device_driver_d3d12.cpp

@@ -2469,7 +2469,7 @@ Error RenderingDeviceDriverD3D12::swap_chain_resize(CommandQueueID p_cmd_queue,
 	DXGI_SWAP_CHAIN_DESC1 swap_chain_desc = {};
 	if (swap_chain->d3d_swap_chain != nullptr) {
 		_swap_chain_release_buffers(swap_chain);
-		res = swap_chain->d3d_swap_chain->ResizeBuffers(p_desired_framebuffer_count, 0, 0, DXGI_FORMAT_UNKNOWN, creation_flags);
+		res = swap_chain->d3d_swap_chain->ResizeBuffers(p_desired_framebuffer_count, surface->width, surface->height, DXGI_FORMAT_UNKNOWN, creation_flags);
 		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_UNAVAILABLE);
 	} else {
 		swap_chain_desc.BufferCount = p_desired_framebuffer_count;
@@ -2478,22 +2478,19 @@ Error RenderingDeviceDriverD3D12::swap_chain_resize(CommandQueueID p_cmd_queue,
 		swap_chain_desc.SwapEffect = DXGI_SWAP_EFFECT_FLIP_DISCARD;
 		swap_chain_desc.SampleDesc.Count = 1;
 		swap_chain_desc.Flags = creation_flags;
-		swap_chain_desc.Scaling = DXGI_SCALING_NONE;
+		swap_chain_desc.Scaling = DXGI_SCALING_STRETCH;
 		if (OS::get_singleton()->is_layered_allowed()) {
 			swap_chain_desc.AlphaMode = DXGI_ALPHA_MODE_PREMULTIPLIED;
 			has_comp_alpha[(uint64_t)p_cmd_queue.id] = true;
 		} else {
 			swap_chain_desc.AlphaMode = DXGI_ALPHA_MODE_IGNORE;
 			has_comp_alpha[(uint64_t)p_cmd_queue.id] = false;
 		}
+		swap_chain_desc.Width = surface->width;
+		swap_chain_desc.Height = surface->height;
 
 		ComPtr<IDXGISwapChain1> swap_chain_1;
-		res = context_driver->dxgi_factory_get()->CreateSwapChainForHwnd(command_queue->d3d_queue.Get(), surface->hwnd, &swap_chain_desc, nullptr, nullptr, swap_chain_1.GetAddressOf());
-		if (!SUCCEEDED(res) && swap_chain_desc.AlphaMode != DXGI_ALPHA_MODE_IGNORE) {
-			swap_chain_desc.AlphaMode = DXGI_ALPHA_MODE_IGNORE;
-			has_comp_alpha[(uint64_t)p_cmd_queue.id] = false;
-			res = context_driver->dxgi_factory_get()->CreateSwapChainForHwnd(command_queue->d3d_queue.Get(), surface->hwnd, &swap_chain_desc, nullptr, nullptr, swap_chain_1.GetAddressOf());
-		}
+		res = context_driver->dxgi_factory_get()->CreateSwapChainForComposition(command_queue->d3d_queue.Get(), &swap_chain_desc, nullptr, swap_chain_1.GetAddressOf());
 		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
 
 		swap_chain_1.As(&swap_chain->d3d_swap_chain);
@@ -2503,6 +2500,36 @@ Error RenderingDeviceDriverD3D12::swap_chain_resize(CommandQueueID p_cmd_queue,
 		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
 	}
 
+	if (surface->composition_device.Get() == nullptr) {
+		using PFN_DCompositionCreateDevice = HRESULT(WINAPI *)(IDXGIDevice *, REFIID, void **);
+		PFN_DCompositionCreateDevice pfn_DCompositionCreateDevice = (PFN_DCompositionCreateDevice)(void *)GetProcAddress(context_driver->lib_dcomp, "DCompositionCreateDevice");
+		ERR_FAIL_NULL_V(pfn_DCompositionCreateDevice, ERR_CANT_CREATE);
+
+		res = pfn_DCompositionCreateDevice(nullptr, IID_PPV_ARGS(surface->composition_device.GetAddressOf()));
+		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
+
+		res = surface->composition_device->CreateTargetForHwnd(surface->hwnd, TRUE, surface->composition_target.GetAddressOf());
+		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
+
+		res = surface->composition_device->CreateVisual(surface->composition_visual.GetAddressOf());
+		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
+
+		res = surface->composition_visual->SetContent(swap_chain->d3d_swap_chain.Get());
+		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
+
+		res = surface->composition_target->SetRoot(surface->composition_visual.Get());
+		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
+
+		res = surface->composition_device->Commit();
+		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
+	} else {
+		res = surface->composition_visual->SetContent(swap_chain->d3d_swap_chain.Get());
+		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
+
+		res = surface->composition_device->Commit();
+		ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
+	}
+
 	res = swap_chain->d3d_swap_chain->GetDesc1(&swap_chain_desc);
 	ERR_FAIL_COND_V(!SUCCEEDED(res), ERR_CANT_CREATE);
 	ERR_FAIL_COND_V(swap_chain_desc.BufferCount == 0, ERR_CANT_CREATE);

platform/windows/display_server_windows.cpp

@@ -2167,6 +2167,10 @@ void DisplayServerWindows::_get_window_style(bool p_main_window, bool p_initiali
 
 	r_style |= WS_CLIPCHILDREN | WS_CLIPSIBLINGS;
 	r_style_ex |= WS_EX_ACCEPTFILES;
+
+	if (OS::get_singleton()->get_current_rendering_driver_name() == "d3d12") {
+		r_style_ex |= WS_EX_NOREDIRECTIONBITMAP;
+	}
 }
 
 void DisplayServerWindows::_update_window_style(WindowID p_window, bool p_repaint) {

platform/windows/display_server_windows.h

@@ -357,6 +357,10 @@ typedef enum _SHC_PROCESS_DPI_AWARENESS {
 	SHC_PROCESS_PER_MONITOR_DPI_AWARE = 2,
 } SHC_PROCESS_DPI_AWARENESS;
 
+#ifndef WS_EX_NOREDIRECTIONBITMAP
+#define WS_EX_NOREDIRECTIONBITMAP 0x00200000L
+#endif
+
 class DropTargetWindows;
 
 class DisplayServerWindows : public DisplayServer {