DirectX 12 Renderer (#5761)

* DirectX 12 Renderer (27 squashed commits)

* Add missing SDL_hidapi.h of merge of SDL.vcxproj.filters

* Fixed OpenWatcom build failure

* Dynapi fix

Co-authored-by: Ryan C. Gordon <icculus@icculus.org>

include/SDL_config.h.cmake

@@ -243,6 +243,7 @@
 
 #cmakedefine HAVE_D3D_H @HAVE_D3D_H@
 #cmakedefine HAVE_D3D11_H @HAVE_D3D11_H@
+#cmakedefine HAVE_D3D12_H @HAVE_D3D12_H@
 #cmakedefine HAVE_DDRAW_H @HAVE_DDRAW_H@
 #cmakedefine HAVE_DSOUND_H @HAVE_DSOUND_H@
 #cmakedefine HAVE_DINPUT_H @HAVE_DINPUT_H@

include/SDL_config.h.in

@@ -413,6 +413,7 @@
 
 #undef SDL_VIDEO_RENDER_D3D
 #undef SDL_VIDEO_RENDER_D3D11
+#undef SDL_VIDEO_RENDER_D3D12
 #undef SDL_VIDEO_RENDER_OGL
 #undef SDL_VIDEO_RENDER_OGL_ES
 #undef SDL_VIDEO_RENDER_OGL_ES2

include/SDL_config_windows.h

@@ -38,6 +38,18 @@
 #include <winsdkver.h>
 #endif
 
+/* sdkddkver.h defines more specific SDK version numbers. This is needed because older versions of the
+ * Windows 10 SDK have broken declarations for the C API for DirectX 12. */
+#if !defined(HAVE_SDKDDKVER_H) && defined(__has_include)
+#if __has_include(<sdkddkver.h>)
+#define HAVE_SDKDDKVER_H 1
+#endif
+#endif
+
+#ifdef HAVE_SDKDDKVER_H
+#include <sdkddkver.h>
+#endif
+
 /* This is a set of defines to configure the SDL features */
 
 #if !defined(_STDINT_H_) && (!defined(HAVE_STDINT_H) || !_HAVE_STDINT_H)
@@ -107,6 +119,9 @@ typedef unsigned int uintptr_t;
 #define HAVE_D3D11_H 1
 #define HAVE_ROAPI_H 1
 #endif
+#if defined(WDK_NTDDI_VERSION) && WDK_NTDDI_VERSION > 0x0A000008 /* 10.0.19041.0 */
+#define HAVE_D3D12_H 1
+#endif
 #define HAVE_MMDEVICEAPI_H 1
 #define HAVE_AUDIOCLIENT_H 1
 #define HAVE_TPCSHRD_H 1
@@ -295,6 +310,9 @@ typedef unsigned int uintptr_t;
 #if !defined(SDL_VIDEO_RENDER_D3D11) && defined(HAVE_D3D11_H)
 #define SDL_VIDEO_RENDER_D3D11  1
 #endif
+#if !defined(SDL_VIDEO_RENDER_D3D12) && defined(HAVE_D3D12_H)
+#define SDL_VIDEO_RENDER_D3D12  1
+#endif
 
 /* Enable OpenGL support */
 #ifndef SDL_VIDEO_OPENGL

include/SDL_config_winrt.h

@@ -250,6 +250,9 @@ typedef unsigned int uintptr_t;
 /* Enable appropriate renderer(s) */
 #define SDL_VIDEO_RENDER_D3D11  1
 
+/* Disable D3D12 as it's not implemented for WinRT */
+#define SDL_VIDEO_RENDER_D3D12  0
+
 #if SDL_VIDEO_OPENGL_ES2
 #define SDL_VIDEO_RENDER_OGL_ES2 1
 #endif

include/SDL_hints.h

@@ -1200,6 +1200,8 @@ extern "C" {
  *
  *  This variable is case insensitive and can be set to the following values:
  *    "direct3d"
+ *    "direct3d11"
+ *    "direct3d12"
  *    "opengl"
  *    "opengles2"
  *    "opengles"

include/SDL_system.h

@@ -102,6 +102,22 @@ typedef struct ID3D11Device ID3D11Device;
  */
 extern DECLSPEC ID3D11Device* SDLCALL SDL_RenderGetD3D11Device(SDL_Renderer * renderer);
 
+typedef struct ID3D12Device ID3D12Device;
+
+/**
+ * Get the D3D12 device associated with a renderer.
+ *
+ * Once you are done using the device, you should release it to avoid a
+ * resource leak.
+ *
+ * \param renderer the renderer from which to get the associated D3D12 device
+ * \returns the D3D12 device associated with given renderer or NULL if it is
+ *          not a D3D12 renderer; call SDL_GetError() for more information.
+ *
+ * \since This function is available since SDL 2.0.23.
+ */
+extern DECLSPEC ID3D12Device* SDLCALL SDL_RenderGetD3D12Device(SDL_Renderer* renderer);
+
 /**
  * Get the DXGI Adapter and Output indices for the specified display index.
  *