/*

 * GStreamer

 * Copyright (C) 2013 Sebastian Dröge <slomo@circular-chaos.org>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <gmodule.h>

/* FIXME: Sharing contexts requires the EGLDisplay to be the same

 * may need to box it.

 */

#include "gstglcontext_egl.h"

#include <gst/gl/gstglcontext_private.h>

#include <gst/gl/gstglfeature.h>

#include <gst/gl/gstglwindow.h>

#include "gstegl.h"

#include "../utils/opengl_versions.h"

#include "../utils/gles_versions.h"

#if GST_GL_HAVE_WINDOW_X11

#include "../x11/gstglwindow_x11.h"

#include <gst/gl/x11/gstgldisplay_x11.h>

#endif

#if GST_GL_HAVE_WINDOW_WAYLAND

#include "../wayland/gstglwindow_wayland_egl.h"

#endif

#if GST_GL_HAVE_WINDOW_WIN32

#include "../win32/gstglwindow_win32.h"

#endif

#if GST_GL_HAVE_WINDOW_DISPMANX

#include "../dispmanx/gstglwindow_dispmanx_egl.h"

#endif

#if GST_GL_HAVE_WINDOW_GBM

#include "../gbm/gstglwindow_gbm_egl.h"

#endif

#define GST_CAT_DEFAULT gst_gl_context_debug

static gboolean gst_gl_context_egl_create_context (GstGLContext * context,

    GstGLAPI gl_api, GstGLContext * other_context, GError ** error);

static void gst_gl_context_egl_destroy_context (GstGLContext * context);

static gboolean gst_gl_context_egl_choose_format (GstGLContext * context,

    GError ** error);

static gboolean gst_gl_context_egl_activate (GstGLContext * context,

    gboolean activate);

static void gst_gl_context_egl_swap_buffers (GstGLContext * context);

static guintptr gst_gl_context_egl_get_gl_context (GstGLContext * context);

static GstGLAPI gst_gl_context_egl_get_gl_api (GstGLContext * context);

static GstGLPlatform gst_gl_context_egl_get_gl_platform (GstGLContext *

    context);

static gboolean gst_gl_context_egl_check_feature (GstGLContext * context,

    const gchar * feature);

static void gst_gl_context_egl_get_gl_platform_version (GstGLContext * context,

    gint * major, gint * minor);

G_DEFINE_TYPE (GstGLContextEGL, gst_gl_context_egl, GST_TYPE_GL_CONTEXT);

static void

gst_gl_context_egl_class_init (GstGLContextEGLClass * klass)

{

  GstGLContextClass *context_class = (GstGLContextClass *) klass;

  context_class->get_gl_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_get_gl_context);

  context_class->activate = GST_DEBUG_FUNCPTR (gst_gl_context_egl_activate);

  context_class->create_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_create_context);

  context_class->destroy_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_destroy_context);

  context_class->choose_format =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_choose_format);

  context_class->swap_buffers =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_swap_buffers);

  context_class->get_gl_api = GST_DEBUG_FUNCPTR (gst_gl_context_egl_get_gl_api);

  context_class->get_gl_platform =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_get_gl_platform);

  context_class->get_proc_address =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_get_proc_address);

  context_class->check_feature =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_check_feature);

  context_class->get_current_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_get_current_context);

  context_class->get_gl_platform_version =

      GST_DEBUG_FUNCPTR (gst_gl_context_egl_get_gl_platform_version);

}

static void

gst_gl_context_egl_init (GstGLContextEGL * context)

{

}

/* Must be called in the gl thread */

GstGLContextEGL *

gst_gl_context_egl_new (GstGLDisplay * display)

{

  GstGLContextEGL *context;

  /* XXX: display type could theoretically be anything, as long as

   * eglGetDisplay supports it. */

  context = g_object_new (GST_TYPE_GL_CONTEXT_EGL, NULL);

  gst_object_ref_sink (context);

  return context;

}

static gboolean

gst_gl_context_egl_choose_format (GstGLContext * context, GError ** error)

{

#if GST_GL_HAVE_WINDOW_X11

  if (GST_IS_GL_WINDOW_X11 (context->window)) {

    GstGLWindow *window = gst_gl_context_get_window (context);

    GstGLWindowX11 *window_x11 = GST_GL_WINDOW_X11 (window);

    gint ret;

    window_x11->visual_info = g_new0 (XVisualInfo, 1);

    ret = XMatchVisualInfo (window_x11->device, window_x11->screen_num,

        window_x11->depth, TrueColor, window_x11->visual_info);

    gst_object_unref (window);

    if (ret == 0) {

      g_set_error (error, GST_GL_CONTEXT_ERROR,

          GST_GL_CONTEXT_ERROR_WRONG_CONFIG, "Failed to match XVisualInfo");

      return FALSE;

    }

  }

#endif

  return TRUE;

}

static gboolean

gst_gl_context_egl_choose_config (GstGLContextEGL * egl, GstGLAPI gl_api,

    gint major, GError ** error)

{

  gboolean create_context;

  EGLint numConfigs;

  gint i = 0;

  EGLint config_attrib[20];

  create_context =

      gst_gl_check_extension ("EGL_KHR_create_context", egl->egl_exts);

  /* silence unused warnings */

  (void) create_context;

  config_attrib[i++] = EGL_SURFACE_TYPE;

  config_attrib[i++] = EGL_WINDOW_BIT;

  config_attrib[i++] = EGL_RENDERABLE_TYPE;

  if (gl_api & GST_GL_API_GLES2) {

    if (major == 3) {

#if defined(EGL_KHR_create_context)

      if (create_context) {

        config_attrib[i++] = EGL_OPENGL_ES3_BIT_KHR;

      } else

#endif

      {

        return FALSE;

      }

    } else {

      config_attrib[i++] = EGL_OPENGL_ES2_BIT;

    }

  } else

    config_attrib[i++] = EGL_OPENGL_BIT;

#if defined(USE_EGL_RPI) && GST_GL_HAVE_WINDOW_WAYLAND

  /* The configurations with a=0 seems to be buggy whereas

   * it works when using dispmanx directly */

  config_attrib[i++] = EGL_ALPHA_SIZE;

  config_attrib[i++] = 1;

#endif

  config_attrib[i++] = EGL_DEPTH_SIZE;

  config_attrib[i++] = 16;

  config_attrib[i++] = EGL_RED_SIZE;

  config_attrib[i++] = 1;

  config_attrib[i++] = EGL_GREEN_SIZE;

  config_attrib[i++] = 1;

  config_attrib[i++] = EGL_BLUE_SIZE;

  config_attrib[i++] = 1;

  config_attrib[i++] = EGL_NONE;

  if (eglChooseConfig (egl->egl_display, config_attrib,

          &egl->egl_config, 1, &numConfigs)) {

    GST_INFO ("config set: %" G_GUINTPTR_FORMAT ", %u",

        (guintptr) egl->egl_config, (unsigned int) numConfigs);

  } else {

    g_set_error (error, GST_GL_CONTEXT_ERROR, GST_GL_CONTEXT_ERROR_WRONG_CONFIG,

        "Failed to set window configuration: %s",

        gst_egl_get_error_string (eglGetError ()));

    goto failure;

  }

  return TRUE;

failure:

  return FALSE;

}

static EGLContext

_create_context_with_flags (GstGLContextEGL * egl, EGLContext share_context,

    GstGLAPI gl_api, gint major, gint minor, gint contextFlags,

    gint profileMask)

{

  gboolean create_context;

#define N_ATTRIBS 20

  gint attribs[N_ATTRIBS];

  gint n = 0;

  /* fail creation of apis/versions/flags that require EGL_KHR_create_context

   * if the extension doesn't exist, namely:0

   *

   * - profile mask

   * - context flags

   * - GL3 > 3.1

   * - GLES2 && minor > 0

   */

  create_context =

      gst_gl_check_extension ("EGL_KHR_create_context", egl->egl_exts);

  (void) create_context;

  if (!create_context && (profileMask || contextFlags

          || ((gl_api & GST_GL_API_OPENGL3)

              && GST_GL_CHECK_GL_VERSION (major, minor, 3, 2))

          || ((gl_api & GST_GL_API_GLES2) && minor > 0))) {

    return 0;

  }

  GST_DEBUG_OBJECT (egl, "attempting to create OpenGL%s context version %d.%d "

      "flags %x profile %x", gl_api & GST_GL_API_GLES2 ? " ES" : "", major,

      minor, contextFlags, profileMask);

#if defined(EGL_KHR_create_context)

  if (create_context) {

    if (major) {

      attribs[n++] = EGL_CONTEXT_MAJOR_VERSION_KHR;

      attribs[n++] = major;

    }

    if (minor) {

      attribs[n++] = EGL_CONTEXT_MINOR_VERSION_KHR;

      attribs[n++] = minor;

    }

    if (contextFlags) {

      attribs[n++] = EGL_CONTEXT_FLAGS_KHR;

      attribs[n++] = contextFlags;

    }

    if (profileMask) {

      attribs[n++] = EGL_CONTEXT_OPENGL_PROFILE_MASK_KHR;

      attribs[n++] = profileMask;

    }

  } else

#endif

  {

    attribs[n++] = EGL_CONTEXT_CLIENT_VERSION;

    attribs[n++] = major;

  }

  attribs[n++] = EGL_NONE;

  g_assert (n < N_ATTRIBS);

#undef N_ATTRIBS

  return eglCreateContext (egl->egl_display, egl->egl_config, share_context,

      attribs);

}

static gboolean

gst_gl_context_egl_create_context (GstGLContext * context,

    GstGLAPI gl_api, GstGLContext * other_context, GError ** error)

{

  GstGLContextEGL *egl;

  GstGLWindow *window = NULL;

  guintptr window_handle = 0;

  EGLint egl_major;

  EGLint egl_minor;

  gboolean need_surface = TRUE;

  guintptr external_gl_context = 0;

  guintptr egl_display;

  egl = GST_GL_CONTEXT_EGL (context);

  window = gst_gl_context_get_window (context);

  GST_DEBUG_OBJECT (context, "Creating EGL context");

  if (other_context) {

    if (gst_gl_context_get_gl_platform (other_context) != GST_GL_PLATFORM_EGL) {

      g_set_error (error, GST_GL_CONTEXT_ERROR,

          GST_GL_CONTEXT_ERROR_WRONG_CONFIG,

          "Cannot share context with non-EGL context");

      goto failure;

    }

    external_gl_context = gst_gl_context_get_gl_context (other_context);

  }

  if ((gl_api & (GST_GL_API_OPENGL | GST_GL_API_OPENGL3 | GST_GL_API_GLES2)) ==

      GST_GL_API_NONE) {

    g_set_error (error, GST_GL_CONTEXT_ERROR, GST_GL_CONTEXT_ERROR_WRONG_API,

        "EGL supports opengl or gles2");

    goto failure;

  }

  if (!egl->display_egl) {

    GstGLDisplay *display = gst_gl_context_get_display (context);

    egl->display_egl = gst_gl_display_egl_from_gl_display (display);

    if (!egl->display_egl) {

      g_set_error (error, GST_GL_CONTEXT_ERROR,

          GST_GL_CONTEXT_ERROR_RESOURCE_UNAVAILABLE,

          "Failed to create EGLDisplay from native display");

      gst_object_unref (display);

      goto failure;

    }

    gst_object_unref (display);

  }

  egl_display = gst_gl_display_get_handle (GST_GL_DISPLAY (egl->display_egl));

  egl->egl_display = (EGLDisplay) egl_display;

  if (eglInitialize (egl->egl_display, &egl_major, &egl_minor)) {

    GST_INFO ("egl initialized, version: %d.%d", egl_major, egl_minor);

  } else {

    g_set_error (error, GST_GL_CONTEXT_ERROR,

        GST_GL_CONTEXT_ERROR_RESOURCE_UNAVAILABLE,

        "Failed to initialize egl: %s",

        gst_egl_get_error_string (eglGetError ()));

    goto failure;

  }

  egl->egl_exts = eglQueryString (egl->egl_display, EGL_EXTENSIONS);

  if (gl_api & (GST_GL_API_OPENGL | GST_GL_API_OPENGL3)) {

    GstGLAPI chosen_gl_api = 0;

    gint i;

    /* egl + opengl only available with EGL 1.4+ */

    if (egl_major == 1 && egl_minor <= 3) {

      if ((gl_api & ~GST_GL_API_OPENGL) == GST_GL_API_NONE) {

        g_set_error (error, GST_GL_CONTEXT_ERROR, GST_GL_CONTEXT_ERROR_OLD_LIBS,

            "EGL version (%i.%i) too old for OpenGL support, (needed at least 1.4)",

            egl_major, egl_minor);

        goto failure;

      } else {

        GST_WARNING

            ("EGL version (%i.%i) too old for OpenGL support, (needed at least 1.4)",

            egl_major, egl_minor);

        if (gl_api & GST_GL_API_GLES2) {

          goto try_gles2;

        } else {

          g_set_error (error, GST_GL_CONTEXT_ERROR,

              GST_GL_CONTEXT_ERROR_WRONG_CONFIG,

              "Failed to choose a suitable OpenGL API");

          goto failure;

        }

      }

    }

    if (!eglBindAPI (EGL_OPENGL_API)) {

      g_set_error (error, GST_GL_CONTEXT_ERROR, GST_GL_CONTEXT_ERROR_FAILED,

          "Failed to bind OpenGL API: %s",

          gst_egl_get_error_string (eglGetError ()));

      goto failure;

    }

    GST_INFO ("Bound OpenGL");

    /* api, version only matters for gles */

    if (!gst_gl_context_egl_choose_config (egl, GST_GL_API_OPENGL, 0, error)) {

      g_assert (error == NULL || *error != NULL);

      goto failure;

    }

    for (i = 0; i < G_N_ELEMENTS (opengl_versions); i++) {

      gint profileMask = 0;

      gint contextFlags = 0;

      if (GST_GL_CHECK_GL_VERSION (opengl_versions[i].major,

              opengl_versions[i].minor, 3, 2)) {

        /* skip gl3 contexts if requested */

        if ((gl_api & GST_GL_API_OPENGL3) == 0)

          continue;

        chosen_gl_api = GST_GL_API_OPENGL3;

#if defined(EGL_KHR_create_context)

        profileMask |= EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT_KHR;

        contextFlags |= EGL_CONTEXT_OPENGL_DEBUG_BIT_KHR;

#endif

      } else if (opengl_versions[i].major == 3 && opengl_versions[i].minor == 1) {

        /* skip 3.1, the implementation is free to give us either a core or a

         * compatibility context (we have no say) */

        continue;

      } else {

        /* skip legacy contexts if requested */

        if ((gl_api & GST_GL_API_OPENGL) == 0)

          continue;

        chosen_gl_api = GST_GL_API_OPENGL;

      }

      egl->egl_context =

          _create_context_with_flags (egl, (EGLContext) external_gl_context,

          chosen_gl_api, opengl_versions[i].major,

          opengl_versions[i].minor, contextFlags, profileMask);

      if (egl->egl_context)

        break;

#if defined(EGL_KHR_create_context)

      profileMask &= ~EGL_CONTEXT_OPENGL_DEBUG_BIT_KHR;

      egl->egl_context =

          _create_context_with_flags (egl, (EGLContext) external_gl_context,

          chosen_gl_api, opengl_versions[i].major,

          opengl_versions[i].minor, contextFlags, profileMask);

      if (egl->egl_context)

        break;

#endif

    }

    egl->gl_api = chosen_gl_api;

  } else if (gl_api & GST_GL_API_GLES2) {

    gint i;

  try_gles2:

    if (!eglBindAPI (EGL_OPENGL_ES_API)) {

      g_set_error (error, GST_GL_CONTEXT_ERROR, GST_GL_CONTEXT_ERROR_FAILED,

          "Failed to bind OpenGL|ES API: %s",

          gst_egl_get_error_string (eglGetError ()));

      goto failure;

    }

    GST_INFO ("Bound OpenGL|ES");

    for (i = 0; i < G_N_ELEMENTS (gles2_versions); i++) {

      gint profileMask = 0;

      gint contextFlags = 0;

      guint maj = gles2_versions[i].major;

      guint min = gles2_versions[i].minor;

      if (!gst_gl_context_egl_choose_config (egl, GST_GL_API_GLES2, maj, error)) {

        GST_DEBUG_OBJECT (context, "Failed to choose a GLES%d config: %s",

            maj, error && *error ? (*error)->message : "Unknown");

        g_clear_error (error);

        continue;

      }

#if defined(EGL_KHR_create_context)

      /* try a debug context */

      contextFlags |= EGL_CONTEXT_OPENGL_DEBUG_BIT_KHR;

      egl->egl_context =

          _create_context_with_flags (egl, (EGLContext) external_gl_context,

          GST_GL_API_GLES2, maj, min, contextFlags, profileMask);

      if (egl->egl_context)

        break;

      /* try without a debug context */

      contextFlags &= ~EGL_CONTEXT_OPENGL_DEBUG_BIT_KHR;

#endif

      egl->egl_context =

          _create_context_with_flags (egl, (EGLContext) external_gl_context,

          GST_GL_API_GLES2, maj, min, contextFlags, profileMask);

      if (egl->egl_context)

        break;

    }

    egl->gl_api = GST_GL_API_GLES2;

  }

  if (egl->egl_context != EGL_NO_CONTEXT) {

    GST_INFO ("gl context created: %" G_GUINTPTR_FORMAT,

        (guintptr) egl->egl_context);

  } else {

    g_set_error (error, GST_GL_CONTEXT_ERROR,

        GST_GL_CONTEXT_ERROR_CREATE_CONTEXT,

        "Failed to create a OpenGL context: %s",

        gst_egl_get_error_string (eglGetError ()));

    goto failure;

  }

  /* FIXME do we want a window vfunc ? */

#if GST_GL_HAVE_WINDOW_X11

  if (GST_IS_GL_WINDOW_X11 (context->window)) {

    gst_gl_window_x11_create_window ((GstGLWindowX11 *) context->window);

  }

#endif

  if (other_context == NULL) {

    /* FIXME: fails to show two outputs at all.  We need a property/option for

     * glimagesink to say its a visible context */

#if GST_GL_HAVE_WINDOW_WAYLAND

    if (GST_IS_GL_WINDOW_WAYLAND_EGL (context->window)) {

      gst_gl_window_wayland_egl_create_window ((GstGLWindowWaylandEGL *)

          context->window);

    }

#endif

#if GST_GL_HAVE_WINDOW_WIN32

    if (GST_IS_GL_WINDOW_WIN32 (context->window)) {

      gst_gl_window_win32_create_window ((GstGLWindowWin32 *) context->window);

    }

#endif

#if GST_GL_HAVE_WINDOW_DISPMANX

    if (GST_IS_GL_WINDOW_DISPMANX_EGL (context->window)) {

      gst_gl_window_dispmanx_egl_create_window ((GstGLWindowDispmanxEGL *)

          context->window);

    }

#endif

#if GST_GL_HAVE_WINDOW_GBM

    if (GST_IS_GL_WINDOW_GBM_EGL (context->window)) {

      gst_gl_window_gbm_egl_create_window ((GstGLWindowGBMEGL *)

          context->window);

    }

#endif

  }

  if (window)

    window_handle = gst_gl_window_get_window_handle (window);

  if (window_handle) {

    GST_DEBUG ("Creating EGLSurface from window_handle %p",

        (void *) window_handle);

    egl->egl_surface =

        eglCreateWindowSurface (egl->egl_display, egl->egl_config,

        (EGLNativeWindowType) window_handle, NULL);

    /* Store window handle for later comparision */

    egl->window_handle = window_handle;

  } else if (!gst_gl_check_extension ("EGL_KHR_surfaceless_context",

          egl->egl_exts)) {

    EGLint surface_attrib[7];

    gint j = 0;

    GST_DEBUG ("Surfaceless context, creating PBufferSurface");

    /* FIXME: Width/height doesn't seem to matter but we can't leave them

     * at 0, otherwise X11 complains about BadValue */

    surface_attrib[j++] = EGL_WIDTH;

    surface_attrib[j++] = 1;

    surface_attrib[j++] = EGL_HEIGHT;

    surface_attrib[j++] = 1;

    surface_attrib[j++] = EGL_LARGEST_PBUFFER;

    surface_attrib[j++] = EGL_TRUE;

    surface_attrib[j++] = EGL_NONE;

    egl->egl_surface =

        eglCreatePbufferSurface (egl->egl_display, egl->egl_config,

        surface_attrib);

  } else {

    GST_DEBUG ("No surface/handle !");

    egl->egl_surface = EGL_NO_SURFACE;

    need_surface = FALSE;

  }

  if (need_surface) {

    if (egl->egl_surface != EGL_NO_SURFACE) {

      GST_INFO ("surface created");

    } else {

      g_set_error (error, GST_GL_CONTEXT_ERROR, GST_GL_CONTEXT_ERROR_FAILED,

          "Failed to create window surface: %s",

          gst_egl_get_error_string (eglGetError ()));

      goto failure;

    }

  }

  egl->egl_major = egl_major;

  egl->egl_minor = egl_minor;

  if (window)

    gst_object_unref (window);

  return TRUE;

failure:

  if (window)

    gst_object_unref (window);

  return FALSE;

}

static void

gst_gl_context_egl_destroy_context (GstGLContext * context)

{

  GstGLContextEGL *egl;

  egl = GST_GL_CONTEXT_EGL (context);

  gst_gl_context_egl_activate (context, FALSE);

  if (egl->egl_surface) {

    eglDestroySurface (egl->egl_display, egl->egl_surface);

    egl->egl_surface = EGL_NO_SURFACE;

  }

  if (egl->egl_context) {

    eglDestroyContext (egl->egl_display, egl->egl_context);

    egl->egl_context = NULL;

  }

  egl->window_handle = 0;

  eglReleaseThread ();

  if (egl->display_egl) {

    gst_object_unref (egl->display_egl);

    egl->display_egl = NULL;

  }

}

static gboolean

gst_gl_context_egl_activate (GstGLContext * context, gboolean activate)

{

  GstGLContextEGL *egl;

  gboolean result;

  egl = GST_GL_CONTEXT_EGL (context);

  if (activate) {

    GstGLWindow *window = gst_gl_context_get_window (context);

    guintptr handle = 0;

    /* Check if the backing handle changed */

    if (window) {

      handle = gst_gl_window_get_window_handle (window);

      gst_object_unref (window);

    }

    if (handle && handle != egl->window_handle) {

      GST_DEBUG_OBJECT (context,

          "Handle changed (have:%p, now:%p), switching surface",

          (void *) egl->window_handle, (void *) handle);

      if (egl->egl_surface) {

        result = eglDestroySurface (egl->egl_display, egl->egl_surface);

        egl->egl_surface = EGL_NO_SURFACE;

        if (!result) {

          GST_ERROR_OBJECT (context, "Failed to destroy old window surface: %s",

              gst_egl_get_error_string (eglGetError ()));

          goto done;

        }

      }

      egl->egl_surface =

          eglCreateWindowSurface (egl->egl_display, egl->egl_config,

          (EGLNativeWindowType) handle, NULL);

      egl->window_handle = handle;

      if (egl->egl_surface == EGL_NO_SURFACE) {

        GST_ERROR_OBJECT (context, "Failed to create window surface: %s",

            gst_egl_get_error_string (eglGetError ()));

        result = FALSE;

        goto done;

      }

    }

    result = eglMakeCurrent (egl->egl_display, egl->egl_surface,

        egl->egl_surface, egl->egl_context);

  } else {

    result = eglMakeCurrent (egl->egl_display, EGL_NO_SURFACE,

        EGL_NO_SURFACE, EGL_NO_CONTEXT);

  }

  if (!result) {

    GST_ERROR_OBJECT (context,

        "Failed to bind context to the current rendering thread: %s",

        gst_egl_get_error_string (eglGetError ()));

  }

done:

  return result;

}

static guintptr

gst_gl_context_egl_get_gl_context (GstGLContext * context)

{

  return (guintptr) GST_GL_CONTEXT_EGL (context)->egl_context;

}

static void

gst_gl_context_egl_swap_buffers (GstGLContext * context)

{

  GstGLContextEGL *egl;

  egl = GST_GL_CONTEXT_EGL (context);

  eglSwapBuffers (egl->egl_display, egl->egl_surface);

}

static GstGLAPI

gst_gl_context_egl_get_gl_api (GstGLContext * context)

{

  return GST_GL_CONTEXT_EGL (context)->gl_api;

}

static GstGLPlatform

gst_gl_context_egl_get_gl_platform (GstGLContext * context)

{

  return GST_GL_PLATFORM_EGL;

}

static GModule *module_egl;

static gpointer

load_egl_module (gpointer user_data)

{

#ifdef GST_GL_LIBEGL_MODULE_NAME

  module_egl = g_module_open (GST_GL_LIBEGL_MODULE_NAME, G_MODULE_BIND_LAZY);

#else

  /* On Linux the .so is only in -dev packages, try with a real soname

   * Proper compilers will optimize away the strcmp */

  if (g_strcmp0 (G_MODULE_SUFFIX, "so") == 0)

    module_egl = g_module_open ("libEGL.so.1", G_MODULE_BIND_LAZY);

  /* This automatically handles the suffix and even .la files */

  if (!module_egl)

    module_egl = g_module_open ("libEGL", G_MODULE_BIND_LAZY);

#endif

  return NULL;

}

gpointer

gst_gl_context_egl_get_proc_address (GstGLAPI gl_api, const gchar * name)

{

  gpointer result = NULL;

  static GOnce g_once = G_ONCE_INIT;

#ifdef __APPLE__

#if GST_GL_HAVE_OPENGL && !defined(GST_GL_LIBGL_MODULE_NAME)

  if (!result && (gl_api & (GST_GL_API_OPENGL | GST_GL_API_OPENGL3))) {

    static GModule *module_opengl = NULL;

    if (g_once_init_enter (&module_opengl)) {

      GModule *setup_module_opengl =

          g_module_open ("libGL.dylib", G_MODULE_BIND_LAZY);

      g_once_init_leave (&module_opengl, setup_module_opengl);

    }

    if (module_opengl)

      g_module_symbol (module_opengl, name, &result);

  }

#endif

#if GST_GL_HAVE_GLES2 && !defined(GST_GL_LIBGLESV2_MODULE_NAME)

  if (!result && (gl_api & (GST_GL_API_GLES2))) {

    static GModule *module_gles2 = NULL;

    if (g_once_init_enter (&module_gles2)) {

      GModule *setup_module_gles2 =

          g_module_open ("libGLESv2.dylib", G_MODULE_BIND_LAZY);

      g_once_init_leave (&module_gles2, setup_module_gles2);

    }

    if (module_gles2)

      g_module_symbol (module_gles2, name, &result);

  }

#endif

#endif // __APPLE__

  if (!result)

    result = gst_gl_context_default_get_proc_address (gl_api, name);

  g_once (&g_once, load_egl_module, NULL);

  if (!result && module_egl) {

    g_module_symbol (module_egl, name, &result);

  }

  /* FIXME: On Android this returns wrong addresses for non-EGL functions */

#if GST_GL_HAVE_WINDOW_ANDROID

  if (!result && g_str_has_prefix (name, "egl")) {

#else

  if (!result) {

    result = eglGetProcAddress (name);

#endif

  }

  return result;

}

static gboolean

gst_gl_context_egl_check_feature (GstGLContext * context, const gchar * feature)

{

  GstGLContextEGL *context_egl = GST_GL_CONTEXT_EGL (context);

  return gst_gl_check_extension (feature, context_egl->egl_exts);

}

guintptr

gst_gl_context_egl_get_current_context (void)

{

  return (guintptr) eglGetCurrentContext ();

}

static void

gst_gl_context_egl_get_gl_platform_version (GstGLContext * context,

    gint * major, gint * minor)

{

  GstGLContextEGL *context_egl = GST_GL_CONTEXT_EGL (context);

  *major = context_egl->egl_major;

  *minor = context_egl->egl_minor;

}