text: /*
    Simple DirectMedia Layer
    Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
  
    This software is provided 'as-is', without any express or implied
    warranty.  In no event will the authors be held liable for any damages
    arising from the use of this software.
  
    Permission is granted to anyone to use this software for any purpose,
    including commercial applications, and to alter it and redistribute it
    freely, subject to the following restrictions:
  
    1. The origin of this software must not be misrepresented; you must not
       claim that you wrote the original software. If you use this software
       in a product, an acknowledgment in the product documentation would be
       appreciated but is not required.
    2. Altered source versions must be plainly marked as such, and must not be
       misrepresented as being the original software.
    3. This notice may not be removed or altered from any source distribution.
  */
  #include "../../SDL_internal.h"
  
  #if SDL_VIDEO_DRIVER_EMSCRIPTEN && SDL_VIDEO_OPENGL_EGL
  
  #include <emscripten/emscripten.h>
  #include <GLES2/gl2.h>
  
  #include "SDL_emscriptenvideo.h"
  #include "SDL_emscriptenopengles.h"
  
  #define LOAD_FUNC(NAME) _this->egl_data->NAME = NAME;
  
  /* EGL implementation of SDL OpenGL support */
  
  int
  Emscripten_GLES_LoadLibrary(_THIS, const char *path) {
      /*we can't load EGL dynamically*/
      _this->egl_data = (struct SDL_EGL_VideoData *) SDL_calloc(1, sizeof(SDL_EGL_VideoData));
      if (!_this->egl_data) {
          return SDL_OutOfMemory();
      }
  
      /* Emscripten forces you to manually cast eglGetProcAddress to the real
         function type; grep for "__eglMustCastToProperFunctionPointerType" in
         Emscripten's egl.h for details. */
      _this->egl_data->eglGetProcAddress = (void *(EGLAPIENTRY *)(const char *)) eglGetProcAddress;
  
      LOAD_FUNC(eglGetDisplay);
      LOAD_FUNC(eglInitialize);
      LOAD_FUNC(eglTerminate);
      LOAD_FUNC(eglChooseConfig);
      LOAD_FUNC(eglGetConfigAttrib);
      LOAD_FUNC(eglCreateContext);
      LOAD_FUNC(eglDestroyContext);
      LOAD_FUNC(eglCreateWindowSurface);
      LOAD_FUNC(eglDestroySurface);
      LOAD_FUNC(eglMakeCurrent);
      LOAD_FUNC(eglSwapBuffers);
      LOAD_FUNC(eglSwapInterval);
      LOAD_FUNC(eglWaitNative);
      LOAD_FUNC(eglWaitGL);
      LOAD_FUNC(eglBindAPI);
      LOAD_FUNC(eglQueryString);
      LOAD_FUNC(eglGetError);
  
      _this->egl_data->egl_display = _this->egl_data->eglGetDisplay(EGL_DEFAULT_DISPLAY);
      if (!_this->egl_data->egl_display) {
          return SDL_SetError("Could not get EGL display");
      }
      
      if (_this->egl_data->eglInitialize(_this->egl_data->egl_display, NULL, NULL) != EGL_TRUE) {
          return SDL_SetError("Could not initialize EGL");
      }
  
      if (path) {
          SDL_strlcpy(_this->gl_config.driver_path, path, sizeof(_this->gl_config.driver_path) - 1);
      } else {
          *_this->gl_config.driver_path = '\0';
      }
      
      return 0;
  }
  
  SDL_EGL_CreateContext_impl(Emscripten)
  SDL_EGL_MakeCurrent_impl(Emscripten)
  
  int
  Emscripten_GLES_SwapWindow(_THIS, SDL_Window * window)
  {
      EGLBoolean ret = SDL_EGL_SwapBuffers(_this, ((SDL_WindowData *) window->driverdata)->egl_surface);
      if (emscripten_has_asyncify()) {
          /* give back control to browser for screen refresh */
          emscripten_sleep(0);
      }
      return ret;
  }
  
  void
  Emscripten_GLES_GetDrawableSize(_THIS, SDL_Window * window, int * w, int * h)
  {
      SDL_WindowData *data;
      if (window->driverdata) {
          data = (SDL_WindowData *) window->driverdata;
  
          if (w) {
              *w = window->w * data->pixel_ratio;
          }
  
          if (h) {
              *h = window->h * data->pixel_ratio;
          }
      }
  }
  
  #endif /* SDL_VIDEO_DRIVER_EMSCRIPTEN && SDL_VIDEO_OPENGL_EGL */
  
  /* vi: set ts=4 sw=4 expandtab: */
  
  