src/video/SDL_egl.c
author Sam Lantinga <slouken@libsdl.org>
Fri, 18 May 2018 13:09:30 -0700
changeset 11983 3a50eb90e4b2
parent 11872 e917e911dab6
child 12028 8aa5a79c8805
permissions -rw-r--r--
Merged latest changes from Steam Link app
     1 /*
     2  *  Simple DirectMedia Layer
     3  *  Copyright (C) 1997-2018 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_OPENGL_EGL
    24 
    25 #if SDL_VIDEO_DRIVER_WINDOWS || SDL_VIDEO_DRIVER_WINRT
    26 #include "../core/windows/SDL_windows.h"
    27 #endif
    28 #if SDL_VIDEO_DRIVER_ANDROID
    29 #include <android/native_window.h>
    30 #endif
    31 
    32 #include "SDL_sysvideo.h"
    33 #include "SDL_log.h"
    34 #include "SDL_egl_c.h"
    35 #include "SDL_loadso.h"
    36 #include "SDL_hints.h"
    37 
    38 #ifdef EGL_KHR_create_context
    39 /* EGL_OPENGL_ES3_BIT_KHR was added in version 13 of the extension. */
    40 #ifndef EGL_OPENGL_ES3_BIT_KHR
    41 #define EGL_OPENGL_ES3_BIT_KHR 0x00000040
    42 #endif
    43 #endif /* EGL_KHR_create_context */
    44 
    45 #if SDL_VIDEO_DRIVER_RPI
    46 /* Raspbian places the OpenGL ES/EGL binaries in a non standard path */
    47 #define DEFAULT_EGL ( vc4 ? "libEGL.so.1" : "libbrcmEGL.so" )
    48 #define DEFAULT_OGL_ES2 ( vc4 ? "libGLESv2.so.2" : "libbrcmGLESv2.so" )
    49 #define ALT_EGL "libEGL.so"
    50 #define ALT_OGL_ES2 "libGLESv2.so"
    51 #define DEFAULT_OGL_ES_PVR ( vc4 ? "libGLES_CM.so.1" : "libbrcmGLESv2.so" )
    52 #define DEFAULT_OGL_ES ( vc4 ? "libGLESv1_CM.so.1" : "libbrcmGLESv2.so" )
    53 
    54 #elif SDL_VIDEO_DRIVER_ANDROID || SDL_VIDEO_DRIVER_VIVANTE
    55 /* Android */
    56 #define DEFAULT_EGL "libEGL.so"
    57 #define DEFAULT_OGL_ES2 "libGLESv2.so"
    58 #define DEFAULT_OGL_ES_PVR "libGLES_CM.so"
    59 #define DEFAULT_OGL_ES "libGLESv1_CM.so"
    60 
    61 #elif SDL_VIDEO_DRIVER_WINDOWS || SDL_VIDEO_DRIVER_WINRT
    62 /* EGL AND OpenGL ES support via ANGLE */
    63 #define DEFAULT_EGL "libEGL.dll"
    64 #define DEFAULT_OGL_ES2 "libGLESv2.dll"
    65 #define DEFAULT_OGL_ES_PVR "libGLES_CM.dll"
    66 #define DEFAULT_OGL_ES "libGLESv1_CM.dll"
    67 
    68 #elif SDL_VIDEO_DRIVER_COCOA
    69 /* EGL AND OpenGL ES support via ANGLE */
    70 #define DEFAULT_EGL "libEGL.dylib"
    71 #define DEFAULT_OGL_ES2 "libGLESv2.dylib"
    72 #define DEFAULT_OGL_ES_PVR "libGLES_CM.dylib"   //???
    73 #define DEFAULT_OGL_ES "libGLESv1_CM.dylib"     //???
    74 
    75 #else
    76 /* Desktop Linux */
    77 #define DEFAULT_OGL "libGL.so.1"
    78 #define DEFAULT_EGL "libEGL.so.1"
    79 #define DEFAULT_OGL_ES2 "libGLESv2.so.2"
    80 #define DEFAULT_OGL_ES_PVR "libGLES_CM.so.1"
    81 #define DEFAULT_OGL_ES "libGLESv1_CM.so.1"
    82 #endif /* SDL_VIDEO_DRIVER_RPI */
    83 
    84 #ifdef SDL_VIDEO_STATIC_ANGLE
    85 #define LOAD_FUNC(NAME) \
    86 _this->egl_data->NAME = (void *)NAME;
    87 #else
    88 #define LOAD_FUNC(NAME) \
    89 _this->egl_data->NAME = SDL_LoadFunction(_this->egl_data->dll_handle, #NAME); \
    90 if (!_this->egl_data->NAME) \
    91 { \
    92     return SDL_SetError("Could not retrieve EGL function " #NAME); \
    93 }
    94 #endif
    95 
    96 static const char * SDL_EGL_GetErrorName(EGLint eglErrorCode)
    97 {
    98 #define SDL_EGL_ERROR_TRANSLATE(e) case e: return #e;
    99     switch (eglErrorCode) {
   100         SDL_EGL_ERROR_TRANSLATE(EGL_SUCCESS);
   101         SDL_EGL_ERROR_TRANSLATE(EGL_NOT_INITIALIZED);
   102         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_ACCESS);
   103         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_ALLOC);
   104         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_ATTRIBUTE);
   105         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_CONTEXT);
   106         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_CONFIG);
   107         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_CURRENT_SURFACE);
   108         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_DISPLAY);
   109         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_SURFACE);
   110         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_MATCH);
   111         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_PARAMETER);
   112         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_NATIVE_PIXMAP);
   113         SDL_EGL_ERROR_TRANSLATE(EGL_BAD_NATIVE_WINDOW);
   114         SDL_EGL_ERROR_TRANSLATE(EGL_CONTEXT_LOST);
   115     }
   116     return "";
   117 }
   118 
   119 int SDL_EGL_SetErrorEx(const char * message, const char * eglFunctionName, EGLint eglErrorCode)
   120 {
   121     const char * errorText = SDL_EGL_GetErrorName(eglErrorCode);
   122     char altErrorText[32];
   123     if (errorText[0] == '\0') {
   124         /* An unknown-to-SDL error code was reported.  Report its hexadecimal value, instead of its name. */
   125         SDL_snprintf(altErrorText, SDL_arraysize(altErrorText), "0x%x", (unsigned int)eglErrorCode);
   126         errorText = altErrorText;
   127     }
   128     return SDL_SetError("%s (call to %s failed, reporting an error of %s)", message, eglFunctionName, errorText);
   129 }
   130 
   131 /* EGL implementation of SDL OpenGL ES support */
   132 typedef enum {
   133     SDL_EGL_DISPLAY_EXTENSION,
   134     SDL_EGL_CLIENT_EXTENSION
   135 } SDL_EGL_ExtensionType;
   136 
   137 static SDL_bool SDL_EGL_HasExtension(_THIS, SDL_EGL_ExtensionType type, const char *ext)
   138 {
   139     size_t ext_len;
   140     const char *ext_override;
   141     const char *egl_extstr;
   142     const char *ext_start;
   143 
   144     /* Invalid extensions can be rejected early */
   145     if (ext == NULL || *ext == 0 || SDL_strchr(ext, ' ') != NULL) {
   146         /* SDL_LogDebug(SDL_LOG_CATEGORY_VIDEO, "SDL_EGL_HasExtension: Invalid EGL extension"); */
   147         return SDL_FALSE;
   148     }
   149 
   150     /* Extensions can be masked with an environment variable.
   151      * Unlike the OpenGL override, this will use the set bits of an integer
   152      * to disable the extension.
   153      *  Bit   Action
   154      *  0     If set, the display extension is masked and not present to SDL.
   155      *  1     If set, the client extension is masked and not present to SDL.
   156      */
   157     ext_override = SDL_getenv(ext);
   158     if (ext_override != NULL) {
   159         int disable_ext = SDL_atoi(ext_override);
   160         if (disable_ext & 0x01 && type == SDL_EGL_DISPLAY_EXTENSION) {
   161             return SDL_FALSE;
   162         } else if (disable_ext & 0x02 && type == SDL_EGL_CLIENT_EXTENSION) {
   163             return SDL_FALSE;
   164         }
   165     }
   166 
   167     ext_len = SDL_strlen(ext);
   168     switch (type) {
   169     case SDL_EGL_DISPLAY_EXTENSION:
   170         egl_extstr = _this->egl_data->eglQueryString(_this->egl_data->egl_display, EGL_EXTENSIONS);
   171         break;
   172     case SDL_EGL_CLIENT_EXTENSION:
   173         /* EGL_EXT_client_extensions modifies eglQueryString to return client extensions
   174          * if EGL_NO_DISPLAY is passed. Implementations without it are required to return NULL.
   175          * This behavior is included in EGL 1.5.
   176          */
   177         egl_extstr = _this->egl_data->eglQueryString(EGL_NO_DISPLAY, EGL_EXTENSIONS);
   178         break;
   179     default:
   180         /* SDL_LogDebug(SDL_LOG_CATEGORY_VIDEO, "SDL_EGL_HasExtension: Invalid extension type"); */
   181         return SDL_FALSE;
   182     }
   183 
   184     if (egl_extstr != NULL) {
   185         ext_start = egl_extstr;
   186 
   187         while (*ext_start) {
   188             ext_start = SDL_strstr(ext_start, ext);
   189             if (ext_start == NULL) {
   190                 return SDL_FALSE;
   191             }
   192             /* Check if the match is not just a substring of one of the extensions */
   193             if (ext_start == egl_extstr || *(ext_start - 1) == ' ') {
   194                 if (ext_start[ext_len] == ' ' || ext_start[ext_len] == 0) {
   195                     return SDL_TRUE;
   196                 }
   197             }
   198             /* If the search stopped in the middle of an extension, skip to the end of it */
   199             ext_start += ext_len;
   200             while (*ext_start != ' ' && *ext_start != 0) {
   201                 ext_start++;
   202             }
   203         }
   204     }
   205 
   206     return SDL_FALSE;
   207 }
   208 
   209 void *
   210 SDL_EGL_GetProcAddress(_THIS, const char *proc)
   211 {
   212     static char procname[1024];
   213     void *retval;
   214     
   215     /* eglGetProcAddress is busted on Android http://code.google.com/p/android/issues/detail?id=7681 */
   216 #if !defined(SDL_VIDEO_DRIVER_ANDROID)
   217     if (_this->egl_data->eglGetProcAddress) {
   218         retval = _this->egl_data->eglGetProcAddress(proc);
   219         if (retval) {
   220             return retval;
   221         }
   222     }
   223 #endif
   224     
   225     retval = SDL_LoadFunction(_this->egl_data->egl_dll_handle, proc);
   226     if (!retval && SDL_strlen(proc) <= 1022) {
   227         procname[0] = '_';
   228         SDL_strlcpy(procname + 1, proc, 1022);
   229         retval = SDL_LoadFunction(_this->egl_data->egl_dll_handle, procname);
   230     }
   231     return retval;
   232 }
   233 
   234 void
   235 SDL_EGL_UnloadLibrary(_THIS)
   236 {
   237     if (_this->egl_data) {
   238         if (_this->egl_data->egl_display) {
   239             _this->egl_data->eglTerminate(_this->egl_data->egl_display);
   240             _this->egl_data->egl_display = NULL;
   241         }
   242 
   243         if (_this->egl_data->dll_handle) {
   244             SDL_UnloadObject(_this->egl_data->dll_handle);
   245             _this->egl_data->dll_handle = NULL;
   246         }
   247         if (_this->egl_data->egl_dll_handle) {
   248             SDL_UnloadObject(_this->egl_data->egl_dll_handle);
   249             _this->egl_data->egl_dll_handle = NULL;
   250         }
   251         
   252         SDL_free(_this->egl_data);
   253         _this->egl_data = NULL;
   254     }
   255 }
   256 
   257 int
   258 SDL_EGL_LoadLibrary(_THIS, const char *egl_path, NativeDisplayType native_display, EGLenum platform)
   259 {
   260     void *dll_handle = NULL, *egl_dll_handle = NULL; /* The naming is counter intuitive, but hey, I just work here -- Gabriel */
   261     const char *path = NULL;
   262     int egl_version_major = 0, egl_version_minor = 0;
   263 #if SDL_VIDEO_DRIVER_WINDOWS || SDL_VIDEO_DRIVER_WINRT
   264     const char *d3dcompiler;
   265 #endif
   266 #if SDL_VIDEO_DRIVER_RPI
   267     SDL_bool vc4 = (0 == access("/sys/module/vc4/", F_OK));
   268 #endif
   269 
   270     if (_this->egl_data) {
   271         return SDL_SetError("EGL context already created");
   272     }
   273 
   274     _this->egl_data = (struct SDL_EGL_VideoData *) SDL_calloc(1, sizeof(SDL_EGL_VideoData));
   275     if (!_this->egl_data) {
   276         return SDL_OutOfMemory();
   277     }
   278 
   279 #if SDL_VIDEO_DRIVER_WINDOWS || SDL_VIDEO_DRIVER_WINRT
   280     d3dcompiler = SDL_GetHint(SDL_HINT_VIDEO_WIN_D3DCOMPILER);
   281     if (!d3dcompiler) {
   282         if (WIN_IsWindowsVistaOrGreater()) {
   283             d3dcompiler = "d3dcompiler_46.dll";
   284         } else {
   285             d3dcompiler = "d3dcompiler_43.dll";
   286         }
   287     }
   288     if (SDL_strcasecmp(d3dcompiler, "none") != 0) {
   289         if (SDL_LoadObject(d3dcompiler) == NULL) {
   290             SDL_ClearError();
   291         }
   292     }
   293 #endif
   294 
   295 #ifndef SDL_VIDEO_STATIC_ANGLE
   296     /* A funny thing, loading EGL.so first does not work on the Raspberry, so we load libGL* first */
   297     path = SDL_getenv("SDL_VIDEO_GL_DRIVER");
   298     if (path != NULL) {
   299         egl_dll_handle = SDL_LoadObject(path);
   300     }
   301 
   302     if (egl_dll_handle == NULL) {
   303         if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES) {
   304             if (_this->gl_config.major_version > 1) {
   305                 path = DEFAULT_OGL_ES2;
   306                 egl_dll_handle = SDL_LoadObject(path);
   307 #ifdef ALT_OGL_ES2
   308                 if (egl_dll_handle == NULL && !vc4) {
   309                     path = ALT_OGL_ES2;
   310                     egl_dll_handle = SDL_LoadObject(path);
   311                 }
   312 #endif
   313 
   314             } else {
   315                 path = DEFAULT_OGL_ES;
   316                 egl_dll_handle = SDL_LoadObject(path);
   317                 if (egl_dll_handle == NULL) {
   318                     path = DEFAULT_OGL_ES_PVR;
   319                     egl_dll_handle = SDL_LoadObject(path);
   320                 }
   321 #ifdef ALT_OGL_ES2
   322                 if (egl_dll_handle == NULL && !vc4) {
   323                     path = ALT_OGL_ES2;
   324                     egl_dll_handle = SDL_LoadObject(path);
   325                 }
   326 #endif
   327             }
   328         }
   329 #ifdef DEFAULT_OGL         
   330         else {
   331             path = DEFAULT_OGL;
   332             egl_dll_handle = SDL_LoadObject(path);
   333         }
   334 #endif        
   335     }
   336     _this->egl_data->egl_dll_handle = egl_dll_handle;
   337 
   338     if (egl_dll_handle == NULL) {
   339         return SDL_SetError("Could not initialize OpenGL / GLES library");
   340     }
   341 
   342     /* Loading libGL* in the previous step took care of loading libEGL.so, but we future proof by double checking */
   343     if (egl_path != NULL) {
   344         dll_handle = SDL_LoadObject(egl_path);
   345     }   
   346     /* Try loading a EGL symbol, if it does not work try the default library paths */
   347     if (dll_handle == NULL || SDL_LoadFunction(dll_handle, "eglChooseConfig") == NULL) {
   348         if (dll_handle != NULL) {
   349             SDL_UnloadObject(dll_handle);
   350         }
   351         path = SDL_getenv("SDL_VIDEO_EGL_DRIVER");
   352         if (path == NULL) {
   353             path = DEFAULT_EGL;
   354         }
   355         dll_handle = SDL_LoadObject(path);
   356 
   357 #ifdef ALT_EGL
   358         if (dll_handle == NULL && !vc4) {
   359             path = ALT_EGL;
   360             dll_handle = SDL_LoadObject(path);
   361         }
   362 #endif
   363 
   364         if (dll_handle == NULL || SDL_LoadFunction(dll_handle, "eglChooseConfig") == NULL) {
   365             if (dll_handle != NULL) {
   366                 SDL_UnloadObject(dll_handle);
   367             }
   368             return SDL_SetError("Could not load EGL library");
   369         }
   370         SDL_ClearError();
   371     }
   372 #endif
   373 
   374     _this->egl_data->dll_handle = dll_handle;
   375 
   376     /* Load new function pointers */
   377     LOAD_FUNC(eglGetDisplay);
   378     LOAD_FUNC(eglInitialize);
   379     LOAD_FUNC(eglTerminate);
   380     LOAD_FUNC(eglGetProcAddress);
   381     LOAD_FUNC(eglChooseConfig);
   382     LOAD_FUNC(eglGetConfigAttrib);
   383     LOAD_FUNC(eglCreateContext);
   384     LOAD_FUNC(eglDestroyContext);
   385     LOAD_FUNC(eglCreatePbufferSurface);
   386     LOAD_FUNC(eglCreateWindowSurface);
   387     LOAD_FUNC(eglDestroySurface);
   388     LOAD_FUNC(eglMakeCurrent);
   389     LOAD_FUNC(eglSwapBuffers);
   390     LOAD_FUNC(eglSwapInterval);
   391     LOAD_FUNC(eglWaitNative);
   392     LOAD_FUNC(eglWaitGL);
   393     LOAD_FUNC(eglBindAPI);
   394     LOAD_FUNC(eglQueryString);
   395     LOAD_FUNC(eglGetError);
   396 
   397     if (_this->egl_data->eglQueryString) {
   398         /* EGL 1.5 allows querying for client version */
   399         const char *egl_version = _this->egl_data->eglQueryString(EGL_NO_DISPLAY, EGL_VERSION);
   400         if (egl_version != NULL) {
   401             if (SDL_sscanf(egl_version, "%d.%d", &egl_version_major, &egl_version_minor) != 2) {
   402                 egl_version_major = 0;
   403                 egl_version_minor = 0;
   404                 SDL_LogWarn(SDL_LOG_CATEGORY_VIDEO, "Could not parse EGL version string: %s", egl_version);
   405             }
   406         }
   407     }
   408 
   409     if (egl_version_major == 1 && egl_version_minor == 5) {
   410         LOAD_FUNC(eglGetPlatformDisplay);
   411     }
   412 
   413     _this->egl_data->egl_display = EGL_NO_DISPLAY;
   414 #if !defined(__WINRT__)
   415     if (platform) {
   416         if (egl_version_major == 1 && egl_version_minor == 5) {
   417             _this->egl_data->egl_display = _this->egl_data->eglGetPlatformDisplay(platform, (void *)(size_t)native_display, NULL);
   418         } else {
   419             if (SDL_EGL_HasExtension(_this, SDL_EGL_CLIENT_EXTENSION, "EGL_EXT_platform_base")) {
   420                 _this->egl_data->eglGetPlatformDisplayEXT = SDL_EGL_GetProcAddress(_this, "eglGetPlatformDisplayEXT");
   421                 if (_this->egl_data->eglGetPlatformDisplayEXT) {
   422                     _this->egl_data->egl_display = _this->egl_data->eglGetPlatformDisplayEXT(platform, (void *)(size_t)native_display, NULL);
   423                 }
   424             }
   425         }
   426     }
   427     /* Try the implementation-specific eglGetDisplay even if eglGetPlatformDisplay fails */
   428     if (_this->egl_data->egl_display == EGL_NO_DISPLAY) {
   429         _this->egl_data->egl_display = _this->egl_data->eglGetDisplay(native_display);
   430     }
   431     if (_this->egl_data->egl_display == EGL_NO_DISPLAY) {
   432         return SDL_SetError("Could not get EGL display");
   433     }
   434     
   435     if (_this->egl_data->eglInitialize(_this->egl_data->egl_display, NULL, NULL) != EGL_TRUE) {
   436         return SDL_SetError("Could not initialize EGL");
   437     }
   438 #endif
   439 
   440     if (path) {
   441         SDL_strlcpy(_this->gl_config.driver_path, path, sizeof(_this->gl_config.driver_path) - 1);
   442     } else {
   443         *_this->gl_config.driver_path = '\0';
   444     }
   445     
   446     return 0;
   447 }
   448 
   449 #ifdef DUMP_EGL_CONFIG
   450 
   451 #define ATTRIBUTE(_attr) { _attr, #_attr }
   452 
   453 typedef struct {
   454     EGLint attribute;
   455     char const* name;
   456 } Attribute;
   457 
   458 Attribute attributes[] = {
   459         ATTRIBUTE( EGL_BUFFER_SIZE ),
   460         ATTRIBUTE( EGL_ALPHA_SIZE ),
   461         ATTRIBUTE( EGL_BLUE_SIZE ),
   462         ATTRIBUTE( EGL_GREEN_SIZE ),
   463         ATTRIBUTE( EGL_RED_SIZE ),
   464         ATTRIBUTE( EGL_DEPTH_SIZE ),
   465         ATTRIBUTE( EGL_STENCIL_SIZE ),
   466         ATTRIBUTE( EGL_CONFIG_CAVEAT ),
   467         ATTRIBUTE( EGL_CONFIG_ID ),
   468         ATTRIBUTE( EGL_LEVEL ),
   469         ATTRIBUTE( EGL_MAX_PBUFFER_HEIGHT ),
   470         ATTRIBUTE( EGL_MAX_PBUFFER_WIDTH ),
   471         ATTRIBUTE( EGL_MAX_PBUFFER_PIXELS ),
   472         ATTRIBUTE( EGL_NATIVE_RENDERABLE ),
   473         ATTRIBUTE( EGL_NATIVE_VISUAL_ID ),
   474         ATTRIBUTE( EGL_NATIVE_VISUAL_TYPE ),
   475         ATTRIBUTE( EGL_SAMPLES ),
   476         ATTRIBUTE( EGL_SAMPLE_BUFFERS ),
   477         ATTRIBUTE( EGL_SURFACE_TYPE ),
   478         ATTRIBUTE( EGL_TRANSPARENT_TYPE ),
   479         ATTRIBUTE( EGL_TRANSPARENT_BLUE_VALUE ),
   480         ATTRIBUTE( EGL_TRANSPARENT_GREEN_VALUE ),
   481         ATTRIBUTE( EGL_TRANSPARENT_RED_VALUE ),
   482         ATTRIBUTE( EGL_BIND_TO_TEXTURE_RGB ),
   483         ATTRIBUTE( EGL_BIND_TO_TEXTURE_RGBA ),
   484         ATTRIBUTE( EGL_MIN_SWAP_INTERVAL ),
   485         ATTRIBUTE( EGL_MAX_SWAP_INTERVAL ),
   486         ATTRIBUTE( EGL_LUMINANCE_SIZE ),
   487         ATTRIBUTE( EGL_ALPHA_MASK_SIZE ),
   488         ATTRIBUTE( EGL_COLOR_BUFFER_TYPE ),
   489         ATTRIBUTE( EGL_RENDERABLE_TYPE ),
   490         ATTRIBUTE( EGL_MATCH_NATIVE_PIXMAP ),
   491         ATTRIBUTE( EGL_CONFORMANT ),
   492 };
   493 
   494 
   495 static void dumpconfig(_THIS, EGLConfig config)
   496 {
   497     int attr;
   498     for (attr = 0 ; attr<sizeof(attributes)/sizeof(Attribute) ; attr++) {
   499         EGLint value;
   500         _this->egl_data->eglGetConfigAttrib(_this->egl_data->egl_display, config, attributes[attr].attribute, &value);
   501         SDL_Log("\t%-32s: %10d (0x%08x)\n", attributes[attr].name, value, value);
   502     }
   503 }
   504 
   505 #endif /* DUMP_EGL_CONFIG */
   506 
   507 int
   508 SDL_EGL_ChooseConfig(_THIS) 
   509 {
   510 /* 64 seems nice. */
   511     EGLint attribs[64];
   512     EGLint found_configs = 0, value;
   513 #ifdef SDL_VIDEO_DRIVER_KMSDRM
   514     /* Intel EGL on KMS/DRM (al least) returns invalid configs that confuse the bitdiff search used */
   515     /* later in this function, so we simply use the first one when using the KMSDRM driver for now. */
   516     EGLConfig configs[1];
   517 #else
   518     /* 128 seems even nicer here */
   519     EGLConfig configs[128];
   520 #endif
   521     int i, j, best_bitdiff = -1, bitdiff;
   522    
   523     if (!_this->egl_data) {
   524         /* The EGL library wasn't loaded, SDL_GetError() should have info */
   525         return -1;
   526     }
   527   
   528     /* Get a valid EGL configuration */
   529     i = 0;
   530     attribs[i++] = EGL_RED_SIZE;
   531     attribs[i++] = _this->gl_config.red_size;
   532     attribs[i++] = EGL_GREEN_SIZE;
   533     attribs[i++] = _this->gl_config.green_size;
   534     attribs[i++] = EGL_BLUE_SIZE;
   535     attribs[i++] = _this->gl_config.blue_size;
   536     
   537     if (_this->gl_config.alpha_size) {
   538         attribs[i++] = EGL_ALPHA_SIZE;
   539         attribs[i++] = _this->gl_config.alpha_size;
   540     }
   541     
   542     if (_this->gl_config.buffer_size) {
   543         attribs[i++] = EGL_BUFFER_SIZE;
   544         attribs[i++] = _this->gl_config.buffer_size;
   545     }
   546     
   547     attribs[i++] = EGL_DEPTH_SIZE;
   548     attribs[i++] = _this->gl_config.depth_size;
   549     
   550     if (_this->gl_config.stencil_size) {
   551         attribs[i++] = EGL_STENCIL_SIZE;
   552         attribs[i++] = _this->gl_config.stencil_size;
   553     }
   554     
   555     if (_this->gl_config.multisamplebuffers) {
   556         attribs[i++] = EGL_SAMPLE_BUFFERS;
   557         attribs[i++] = _this->gl_config.multisamplebuffers;
   558     }
   559     
   560     if (_this->gl_config.multisamplesamples) {
   561         attribs[i++] = EGL_SAMPLES;
   562         attribs[i++] = _this->gl_config.multisamplesamples;
   563     }
   564 
   565     attribs[i++] = EGL_RENDERABLE_TYPE;
   566     if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES) {
   567 #ifdef EGL_KHR_create_context
   568         if (_this->gl_config.major_version >= 3 &&
   569             SDL_EGL_HasExtension(_this, SDL_EGL_DISPLAY_EXTENSION, "EGL_KHR_create_context")) {
   570             attribs[i++] = EGL_OPENGL_ES3_BIT_KHR;
   571         } else
   572 #endif
   573         if (_this->gl_config.major_version >= 2) {
   574             attribs[i++] = EGL_OPENGL_ES2_BIT;
   575         } else {
   576             attribs[i++] = EGL_OPENGL_ES_BIT;
   577         }
   578         _this->egl_data->eglBindAPI(EGL_OPENGL_ES_API);
   579     } else {
   580         attribs[i++] = EGL_OPENGL_BIT;
   581         _this->egl_data->eglBindAPI(EGL_OPENGL_API);
   582     }
   583 
   584     if (_this->egl_data->egl_surfacetype) {
   585         attribs[i++] = EGL_SURFACE_TYPE;
   586         attribs[i++] = _this->egl_data->egl_surfacetype;
   587     }
   588 
   589     attribs[i++] = EGL_NONE;
   590 
   591     if (_this->egl_data->eglChooseConfig(_this->egl_data->egl_display,
   592         attribs,
   593         configs, SDL_arraysize(configs),
   594         &found_configs) == EGL_FALSE ||
   595         found_configs == 0) {
   596         return SDL_EGL_SetError("Couldn't find matching EGL config", "eglChooseConfig");
   597     }
   598 
   599     /* eglChooseConfig returns a number of configurations that match or exceed the requested attribs. */
   600     /* From those, we select the one that matches our requirements more closely via a makeshift algorithm */
   601 
   602     for (i = 0; i < found_configs; i++ ) {
   603         bitdiff = 0;
   604         for (j = 0; j < SDL_arraysize(attribs) - 1; j += 2) {
   605             if (attribs[j] == EGL_NONE) {
   606                break;
   607             }
   608             
   609             if ( attribs[j+1] != EGL_DONT_CARE && (
   610                 attribs[j] == EGL_RED_SIZE ||
   611                 attribs[j] == EGL_GREEN_SIZE ||
   612                 attribs[j] == EGL_BLUE_SIZE ||
   613                 attribs[j] == EGL_ALPHA_SIZE ||
   614                 attribs[j] == EGL_DEPTH_SIZE ||
   615                 attribs[j] == EGL_STENCIL_SIZE)) {
   616                 _this->egl_data->eglGetConfigAttrib(_this->egl_data->egl_display, configs[i], attribs[j], &value);
   617                 bitdiff += value - attribs[j + 1]; /* value is always >= attrib */
   618             }
   619         }
   620 
   621         if (bitdiff < best_bitdiff || best_bitdiff == -1) {
   622             _this->egl_data->egl_config = configs[i];
   623             
   624             best_bitdiff = bitdiff;
   625         }
   626 
   627         if (bitdiff == 0) {
   628             break; /* we found an exact match! */
   629         }
   630     }
   631 
   632 #ifdef DUMP_EGL_CONFIG
   633     dumpconfig(_this, _this->egl_data->egl_config);
   634 #endif
   635     
   636     return 0;
   637 }
   638 
   639 SDL_GLContext
   640 SDL_EGL_CreateContext(_THIS, EGLSurface egl_surface)
   641 {
   642     /* max 14 values plus terminator. */
   643     EGLint attribs[15];
   644     int attr = 0;
   645 
   646     EGLContext egl_context, share_context = EGL_NO_CONTEXT;
   647     EGLint profile_mask = _this->gl_config.profile_mask;
   648     EGLint major_version = _this->gl_config.major_version;
   649     EGLint minor_version = _this->gl_config.minor_version;
   650     SDL_bool profile_es = (profile_mask == SDL_GL_CONTEXT_PROFILE_ES);
   651 
   652     if (!_this->egl_data) {
   653         /* The EGL library wasn't loaded, SDL_GetError() should have info */
   654         return NULL;
   655     }
   656 
   657     if (_this->gl_config.share_with_current_context) {
   658         share_context = (EGLContext)SDL_GL_GetCurrentContext();
   659     }
   660 
   661     /* Set the context version and other attributes. */
   662     if ((major_version < 3 || (minor_version == 0 && profile_es)) &&
   663         _this->gl_config.flags == 0 &&
   664         (profile_mask == 0 || profile_es)) {
   665         /* Create a context without using EGL_KHR_create_context attribs.
   666          * When creating a GLES context without EGL_KHR_create_context we can
   667          * only specify the major version. When creating a desktop GL context
   668          * we can't specify any version, so we only try in that case when the
   669          * version is less than 3.0 (matches SDL's GLX/WGL behavior.)
   670          */
   671         if (profile_es) {
   672             attribs[attr++] = EGL_CONTEXT_CLIENT_VERSION;
   673             attribs[attr++] = SDL_max(major_version, 1);
   674         }
   675     } else {
   676 #ifdef EGL_KHR_create_context
   677         /* The Major/minor version, context profiles, and context flags can
   678          * only be specified when this extension is available.
   679          */
   680         if (SDL_EGL_HasExtension(_this, SDL_EGL_DISPLAY_EXTENSION, "EGL_KHR_create_context")) {
   681             attribs[attr++] = EGL_CONTEXT_MAJOR_VERSION_KHR;
   682             attribs[attr++] = major_version;
   683             attribs[attr++] = EGL_CONTEXT_MINOR_VERSION_KHR;
   684             attribs[attr++] = minor_version;
   685 
   686             /* SDL profile bits match EGL profile bits. */
   687             if (profile_mask != 0 && profile_mask != SDL_GL_CONTEXT_PROFILE_ES) {
   688                 attribs[attr++] = EGL_CONTEXT_OPENGL_PROFILE_MASK_KHR;
   689                 attribs[attr++] = profile_mask;
   690             }
   691 
   692             /* SDL flags match EGL flags. */
   693             if (_this->gl_config.flags != 0) {
   694                 attribs[attr++] = EGL_CONTEXT_FLAGS_KHR;
   695                 attribs[attr++] = _this->gl_config.flags;
   696             }
   697         } else
   698 #endif /* EGL_KHR_create_context */
   699         {
   700             SDL_SetError("Could not create EGL context (context attributes are not supported)");
   701             return NULL;
   702         }
   703     }
   704 
   705     if (_this->gl_config.no_error) {
   706 #ifdef EGL_KHR_create_context_no_error
   707         if (SDL_EGL_HasExtension(_this, SDL_EGL_DISPLAY_EXTENSION, "EGL_KHR_create_context_no_error")) {
   708             attribs[attr++] = EGL_CONTEXT_OPENGL_NO_ERROR_KHR;
   709             attribs[attr++] = _this->gl_config.no_error;
   710         } else
   711 #endif
   712         {
   713             SDL_SetError("EGL implementation does not support no_error contexts");
   714             return NULL;
   715         }
   716     }
   717 
   718     attribs[attr++] = EGL_NONE;
   719 
   720     /* Bind the API */
   721     if (profile_es) {
   722         _this->egl_data->eglBindAPI(EGL_OPENGL_ES_API);
   723     } else {
   724         _this->egl_data->eglBindAPI(EGL_OPENGL_API);
   725     }
   726 
   727     egl_context = _this->egl_data->eglCreateContext(_this->egl_data->egl_display,
   728                                       _this->egl_data->egl_config,
   729                                       share_context, attribs);
   730 
   731     if (egl_context == EGL_NO_CONTEXT) {
   732         SDL_EGL_SetError("Could not create EGL context", "eglCreateContext");
   733         return NULL;
   734     }
   735 
   736     _this->egl_data->egl_swapinterval = 0;
   737 
   738     if (SDL_EGL_MakeCurrent(_this, egl_surface, egl_context) < 0) {
   739         /* Save the SDL error set by SDL_EGL_MakeCurrent */
   740         char errorText[1024];
   741         SDL_strlcpy(errorText, SDL_GetError(), SDL_arraysize(errorText));
   742 
   743         /* Delete the context, which may alter the value returned by SDL_GetError() */
   744         SDL_EGL_DeleteContext(_this, egl_context);
   745 
   746         /* Restore the SDL error */
   747         SDL_SetError("%s", errorText);
   748 
   749         return NULL;
   750     }
   751 
   752     return (SDL_GLContext) egl_context;
   753 }
   754 
   755 int
   756 SDL_EGL_MakeCurrent(_THIS, EGLSurface egl_surface, SDL_GLContext context)
   757 {
   758     EGLContext egl_context = (EGLContext) context;
   759 
   760     if (!_this->egl_data) {
   761         return SDL_SetError("OpenGL not initialized");
   762     }
   763     
   764     /* The android emulator crashes badly if you try to eglMakeCurrent 
   765      * with a valid context and invalid surface, so we have to check for both here.
   766      */
   767     if (!egl_context || !egl_surface) {
   768          _this->egl_data->eglMakeCurrent(_this->egl_data->egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
   769     } else {
   770         if (!_this->egl_data->eglMakeCurrent(_this->egl_data->egl_display,
   771             egl_surface, egl_surface, egl_context)) {
   772             return SDL_EGL_SetError("Unable to make EGL context current", "eglMakeCurrent");
   773         }
   774     }
   775       
   776     return 0;
   777 }
   778 
   779 int
   780 SDL_EGL_SetSwapInterval(_THIS, int interval)
   781 {
   782     EGLBoolean status;
   783     
   784     if (!_this->egl_data) {
   785         return SDL_SetError("EGL not initialized");
   786     }
   787     
   788     status = _this->egl_data->eglSwapInterval(_this->egl_data->egl_display, interval);
   789     if (status == EGL_TRUE) {
   790         _this->egl_data->egl_swapinterval = interval;
   791         return 0;
   792     }
   793     
   794     return SDL_EGL_SetError("Unable to set the EGL swap interval", "eglSwapInterval");
   795 }
   796 
   797 int
   798 SDL_EGL_GetSwapInterval(_THIS)
   799 {
   800     if (!_this->egl_data) {
   801         SDL_SetError("EGL not initialized");
   802         return 0;
   803     }
   804     
   805     return _this->egl_data->egl_swapinterval;
   806 }
   807 
   808 int
   809 SDL_EGL_SwapBuffers(_THIS, EGLSurface egl_surface)
   810 {
   811     if (!_this->egl_data->eglSwapBuffers(_this->egl_data->egl_display, egl_surface)) {
   812         return SDL_EGL_SetError("unable to show color buffer in an OS-native window", "eglSwapBuffers");
   813     }
   814     return 0;
   815 }
   816 
   817 void
   818 SDL_EGL_DeleteContext(_THIS, SDL_GLContext context)
   819 {
   820     EGLContext egl_context = (EGLContext) context;
   821 
   822     /* Clean up GLES and EGL */
   823     if (!_this->egl_data) {
   824         return;
   825     }
   826     
   827     if (egl_context != NULL && egl_context != EGL_NO_CONTEXT) {
   828         SDL_EGL_MakeCurrent(_this, NULL, NULL);
   829         _this->egl_data->eglDestroyContext(_this->egl_data->egl_display, egl_context);
   830     }
   831         
   832 }
   833 
   834 EGLSurface *
   835 SDL_EGL_CreateSurface(_THIS, NativeWindowType nw) 
   836 {
   837     /* max 2 values plus terminator. */
   838     EGLint attribs[3];
   839     int attr = 0;
   840 	
   841     EGLSurface * surface;
   842 
   843     if (SDL_EGL_ChooseConfig(_this) != 0) {
   844         return EGL_NO_SURFACE;
   845     }
   846     
   847 #if SDL_VIDEO_DRIVER_ANDROID
   848     {
   849         /* Android docs recommend doing this!
   850          * Ref: http://developer.android.com/reference/android/app/NativeActivity.html 
   851          */
   852         EGLint format;
   853         _this->egl_data->eglGetConfigAttrib(_this->egl_data->egl_display,
   854                                             _this->egl_data->egl_config, 
   855                                             EGL_NATIVE_VISUAL_ID, &format);
   856 
   857         ANativeWindow_setBuffersGeometry(nw, 0, 0, format);
   858     }
   859 #endif    
   860     if (_this->gl_config.framebuffer_srgb_capable) {
   861 #ifdef EGL_KHR_gl_colorspace
   862         if (SDL_EGL_HasExtension(_this, SDL_EGL_DISPLAY_EXTENSION, "EGL_KHR_gl_colorspace")) {
   863             attribs[attr++] = EGL_GL_COLORSPACE_KHR;
   864             attribs[attr++] = EGL_GL_COLORSPACE_SRGB_KHR;
   865         } else
   866 #endif
   867         {
   868             SDL_SetError("EGL implementation does not support sRGB system framebuffers");
   869             return EGL_NO_SURFACE;
   870         }
   871     }
   872 	
   873     attribs[attr++] = EGL_NONE;
   874     
   875     surface = _this->egl_data->eglCreateWindowSurface(
   876             _this->egl_data->egl_display,
   877             _this->egl_data->egl_config,
   878             nw, &attribs[0]);
   879     if (surface == EGL_NO_SURFACE) {
   880         SDL_EGL_SetError("unable to create an EGL window surface", "eglCreateWindowSurface");
   881     }
   882     return surface;
   883 }
   884 
   885 void
   886 SDL_EGL_DestroySurface(_THIS, EGLSurface egl_surface) 
   887 {
   888     if (!_this->egl_data) {
   889         return;
   890     }
   891     
   892     if (egl_surface != EGL_NO_SURFACE) {
   893         _this->egl_data->eglDestroySurface(_this->egl_data->egl_display, egl_surface);
   894     }
   895 }
   896 
   897 #endif /* SDL_VIDEO_OPENGL_EGL */
   898 
   899 /* vi: set ts=4 sw=4 expandtab: */
   900