src/video/winrt/SDL_winrtopengles.cpp
author Sam Lantinga <slouken@libsdl.org>
Wed, 02 Aug 2017 10:22:48 -0700
changeset 11175 cbc6a8a5b701
parent 10740 bb53965b659d
child 11811 5d94cb6b24d3
permissions -rw-r--r--
Fixed bug 3690 - SDL2 KMS/DRM render context support

Manuel

The attached patch adds support for KMS/DRM context graphics.

It builds with no problem on X86_64 GNU/Linux systems, provided the needed libraries are present, and on ARM GNU/Linux systems that have KMS/DRM support and a GLES2 implementation.
Tested on Raspberry Pi: KMS/DRM is what the Raspberry Pi will use as default in the near future, once the propietary DispmanX API by Broadcom is overtaken by open graphics stack, it's possible to boot current Raspbian system in KMS mode by adding "dtoverlay=vc4-kms-v3d" to config.txt on Raspbian's boot partition.
X86 systems use KMS right away in every current GNU/Linux system.

Simple build instructions:

$./autogen.sh
$./configure --enable-video-kmsdrm
$make
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2017 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 #include "../../SDL_internal.h"
    22 
    23 #if SDL_VIDEO_DRIVER_WINRT && SDL_VIDEO_OPENGL_EGL
    24 
    25 /* EGL implementation of SDL OpenGL support */
    26 
    27 #include "SDL_winrtvideo_cpp.h"
    28 extern "C" {
    29 #include "SDL_winrtopengles.h"
    30 #include "SDL_loadso.h"
    31 #include "../SDL_egl_c.h"
    32 }
    33 
    34 /* Windows includes */
    35 #include <wrl/client.h>
    36 using namespace Windows::UI::Core;
    37 
    38 /* ANGLE/WinRT constants */
    39 static const int ANGLE_D3D_FEATURE_LEVEL_ANY = 0;
    40 #define EGL_PLATFORM_ANGLE_ANGLE                        0x3202
    41 #define EGL_PLATFORM_ANGLE_TYPE_ANGLE                   0x3203
    42 #define EGL_PLATFORM_ANGLE_MAX_VERSION_MAJOR_ANGLE      0x3204
    43 #define EGL_PLATFORM_ANGLE_MAX_VERSION_MINOR_ANGLE      0x3205
    44 #define EGL_PLATFORM_ANGLE_TYPE_D3D11_ANGLE             0x3208
    45 #define EGL_PLATFORM_ANGLE_DEVICE_TYPE_ANGLE            0x3209
    46 #define EGL_PLATFORM_ANGLE_DEVICE_TYPE_WARP_ANGLE       0x320B
    47 #define EGL_PLATFORM_ANGLE_ENABLE_AUTOMATIC_TRIM_ANGLE  0x320F
    48 
    49 #define EGL_ANGLE_DISPLAY_ALLOW_RENDER_TO_BACK_BUFFER   0x320B
    50 
    51 
    52 /*
    53  * SDL/EGL top-level implementation
    54  */
    55 
    56 extern "C" int
    57 WINRT_GLES_LoadLibrary(_THIS, const char *path)
    58 {
    59     SDL_VideoData *video_data = (SDL_VideoData *)_this->driverdata;
    60 
    61     if (SDL_EGL_LoadLibrary(_this, path, EGL_DEFAULT_DISPLAY, 0) != 0) {
    62         return -1;
    63     }
    64 
    65     /* Load ANGLE/WinRT-specific functions */
    66     CreateWinrtEglWindow_Old_Function CreateWinrtEglWindow = (CreateWinrtEglWindow_Old_Function) SDL_LoadFunction(_this->egl_data->egl_dll_handle, "CreateWinrtEglWindow");
    67     if (CreateWinrtEglWindow) {
    68         /* 'CreateWinrtEglWindow' was found, which means that an an older
    69          * version of ANGLE/WinRT is being used.  Continue setting up EGL,
    70          * as appropriate to this version of ANGLE.
    71          */
    72 
    73         /* Create an ANGLE/WinRT EGL-window */
    74         /* TODO, WinRT: check for XAML usage before accessing the CoreWindow, as not doing so could lead to a crash */
    75         CoreWindow ^ native_win = CoreWindow::GetForCurrentThread();
    76         Microsoft::WRL::ComPtr<IUnknown> cpp_win = reinterpret_cast<IUnknown *>(native_win);
    77         HRESULT result = CreateWinrtEglWindow(cpp_win, ANGLE_D3D_FEATURE_LEVEL_ANY, &(video_data->winrtEglWindow));
    78         if (FAILED(result)) {
    79             return -1;
    80         }
    81 
    82         /* Call eglGetDisplay and eglInitialize as appropriate.  On other
    83          * platforms, this would probably get done by SDL_EGL_LoadLibrary,
    84          * however ANGLE/WinRT's current implementation (as of Mar 22, 2014) of
    85          * eglGetDisplay requires that a C++ object be passed into it, so the
    86          * call will be made in this file, a C++ file, instead.
    87          */
    88         Microsoft::WRL::ComPtr<IUnknown> cpp_display = video_data->winrtEglWindow;
    89         _this->egl_data->egl_display = ((eglGetDisplay_Old_Function)_this->egl_data->eglGetDisplay)(cpp_display);
    90         if (!_this->egl_data->egl_display) {
    91             return SDL_EGL_SetError("Could not get Windows 8.0 EGL display", "eglGetDisplay");
    92         }
    93 
    94         if (_this->egl_data->eglInitialize(_this->egl_data->egl_display, NULL, NULL) != EGL_TRUE) {
    95             return SDL_EGL_SetError("Could not initialize Windows 8.0 EGL", "eglInitialize");
    96         }
    97     } else {
    98         /* Declare some ANGLE/EGL initialization property-sets, as suggested by
    99          * MSOpenTech's ANGLE-for-WinRT template apps:
   100          */
   101         const EGLint defaultDisplayAttributes[] =
   102         {
   103             EGL_PLATFORM_ANGLE_TYPE_ANGLE, EGL_PLATFORM_ANGLE_TYPE_D3D11_ANGLE,
   104             EGL_ANGLE_DISPLAY_ALLOW_RENDER_TO_BACK_BUFFER, EGL_TRUE,
   105             EGL_PLATFORM_ANGLE_ENABLE_AUTOMATIC_TRIM_ANGLE, EGL_TRUE,
   106             EGL_NONE,
   107         };
   108 
   109         const EGLint fl9_3DisplayAttributes[] =
   110         {
   111             EGL_PLATFORM_ANGLE_TYPE_ANGLE, EGL_PLATFORM_ANGLE_TYPE_D3D11_ANGLE,
   112             EGL_PLATFORM_ANGLE_MAX_VERSION_MAJOR_ANGLE, 9,
   113             EGL_PLATFORM_ANGLE_MAX_VERSION_MINOR_ANGLE, 3,
   114             EGL_ANGLE_DISPLAY_ALLOW_RENDER_TO_BACK_BUFFER, EGL_TRUE,
   115             EGL_PLATFORM_ANGLE_ENABLE_AUTOMATIC_TRIM_ANGLE, EGL_TRUE,
   116             EGL_NONE,
   117         };
   118 
   119         const EGLint warpDisplayAttributes[] =
   120         {
   121             EGL_PLATFORM_ANGLE_TYPE_ANGLE, EGL_PLATFORM_ANGLE_TYPE_D3D11_ANGLE,
   122             EGL_PLATFORM_ANGLE_DEVICE_TYPE_ANGLE, EGL_PLATFORM_ANGLE_DEVICE_TYPE_WARP_ANGLE,
   123             EGL_ANGLE_DISPLAY_ALLOW_RENDER_TO_BACK_BUFFER, EGL_TRUE,
   124             EGL_PLATFORM_ANGLE_ENABLE_AUTOMATIC_TRIM_ANGLE, EGL_TRUE,
   125             EGL_NONE,
   126         };
   127 
   128         /* 'CreateWinrtEglWindow' was NOT found, which either means that a
   129          * newer version of ANGLE/WinRT is being used, or that we don't have
   130          * a valid copy of ANGLE.
   131          *
   132          * Try loading ANGLE as if it were the newer version.
   133          */
   134         eglGetPlatformDisplayEXT_Function eglGetPlatformDisplayEXT = (eglGetPlatformDisplayEXT_Function)_this->egl_data->eglGetProcAddress("eglGetPlatformDisplayEXT");
   135         if (!eglGetPlatformDisplayEXT) {
   136             return SDL_EGL_SetError("Could not retrieve ANGLE/WinRT display function(s)", "eglGetProcAddress");
   137         }
   138 
   139 #if (WINAPI_FAMILY != WINAPI_FAMILY_PHONE_APP)
   140         /* Try initializing EGL at D3D11 Feature Level 10_0+ (which is not
   141          * supported on WinPhone 8.x.
   142          */
   143         _this->egl_data->egl_display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE, EGL_DEFAULT_DISPLAY, defaultDisplayAttributes);
   144         if (!_this->egl_data->egl_display) {
   145             return SDL_EGL_SetError("Could not get EGL display for Direct3D 10_0+", "eglGetPlatformDisplayEXT");
   146         }
   147 
   148         if (_this->egl_data->eglInitialize(_this->egl_data->egl_display, NULL, NULL) != EGL_TRUE)
   149 #endif
   150         {
   151             /* Try initializing EGL at D3D11 Feature Level 9_3, in case the
   152              * 10_0 init fails, or we're on Windows Phone (which only supports
   153              * 9_3).
   154              */
   155             _this->egl_data->egl_display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE, EGL_DEFAULT_DISPLAY, fl9_3DisplayAttributes);
   156             if (!_this->egl_data->egl_display) {
   157                 return SDL_EGL_SetError("Could not get EGL display for Direct3D 9_3", "eglGetPlatformDisplayEXT");
   158             }
   159 
   160             if (_this->egl_data->eglInitialize(_this->egl_data->egl_display, NULL, NULL) != EGL_TRUE) {
   161                 /* Try initializing EGL at D3D11 Feature Level 11_0 on WARP
   162                  * (a Windows-provided, software rasterizer) if all else fails.
   163                  */
   164                 _this->egl_data->egl_display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE, EGL_DEFAULT_DISPLAY, warpDisplayAttributes);
   165                 if (!_this->egl_data->egl_display) {
   166                     return SDL_EGL_SetError("Could not get EGL display for Direct3D WARP", "eglGetPlatformDisplayEXT");
   167                 }
   168 
   169                 if (_this->egl_data->eglInitialize(_this->egl_data->egl_display, NULL, NULL) != EGL_TRUE) {
   170                     return SDL_EGL_SetError("Could not initialize WinRT 8.x+ EGL", "eglInitialize");
   171                 }
   172             }
   173         }
   174     }
   175 
   176     return 0;
   177 }
   178 
   179 extern "C" void
   180 WINRT_GLES_UnloadLibrary(_THIS)
   181 {
   182     SDL_VideoData *video_data = (SDL_VideoData *)_this->driverdata;
   183 
   184     /* Release SDL's own COM reference to the ANGLE/WinRT IWinrtEglWindow */
   185     if (video_data->winrtEglWindow) {
   186         video_data->winrtEglWindow->Release();
   187         video_data->winrtEglWindow = nullptr;
   188     }
   189 
   190     /* Perform the bulk of the unloading */
   191     SDL_EGL_UnloadLibrary(_this);
   192 }
   193 
   194 extern "C" {
   195 SDL_EGL_CreateContext_impl(WINRT)
   196 SDL_EGL_SwapWindow_impl(WINRT)
   197 SDL_EGL_MakeCurrent_impl(WINRT)
   198 }
   199 
   200 #endif /* SDL_VIDEO_DRIVER_WINRT && SDL_VIDEO_OPENGL_EGL */
   201 
   202 /* vi: set ts=4 sw=4 expandtab: */
   203