mutter/cogl/winsys/cogl-winsys-egl-null.c
Robert Bragg 010d16f647 Adds initial GLES2 integration support
This makes it possible to integrate existing GLES2 code with
applications using Cogl as the rendering api.

Currently all GLES2 usage is handled with separate GLES2 contexts to
ensure that GLES2 api usage doesn't interfere with Cogl's own use of
OpenGL[ES]. The api has been designed though so we can provide tighter
integration later.

The api would allow us to support GLES2 virtualized on top of an
OpenGL/GLX driver as well as GLES2 virtualized on the core rendering api
of Cogl itself. Virtualizing the GLES2 support on Cogl will allow us to
take advantage of Cogl debugging facilities as well as let us optimize
the cost of allocating multiple GLES2 contexts and switching between
them which can both be very expensive with many drivers.

As as a side effect of this patch Cogl can also now be used as a
portable window system binding API for GLES2 as an alternative to EGL.

Parts of this patch are based on work done by Tomeu Vizoso
<tomeu.vizoso@collabora.com> who did the first iteration of adding GLES2
API support to Cogl so that WebGL support could be added to
webkit-clutter.

This patch adds a very minimal cogl-gles2-context example that shows how
to create a gles2 context, clear the screen to a random color and also
draw a triangle with the cogl api.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
(cherry picked from commit 4bb6eff3dbd50d8fef7d6bdbed55c5aaa70036a8)
2012-08-06 14:27:42 +01:00

241 lines
6.8 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2011 Intel Corporation.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*
*
* Authors:
* Robert Bragg <robert@linux.intel.com>
* Neil Roberts <neil@linux.intel.com>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl-winsys-egl-null-private.h"
#include "cogl-winsys-egl-private.h"
#include "cogl-renderer-private.h"
#include "cogl-framebuffer-private.h"
#include "cogl-onscreen-private.h"
static const CoglWinsysEGLVtable _cogl_winsys_egl_vtable;
typedef struct _CoglDisplayNull
{
int egl_surface_width;
int egl_surface_height;
CoglBool have_onscreen;
} CoglDisplayNull;
static void
_cogl_winsys_renderer_disconnect (CoglRenderer *renderer)
{
CoglRendererEGL *egl_renderer = renderer->winsys;
eglTerminate (egl_renderer->edpy);
g_slice_free (CoglRendererEGL, egl_renderer);
}
static CoglBool
_cogl_winsys_renderer_connect (CoglRenderer *renderer,
GError **error)
{
CoglRendererEGL *egl_renderer;
renderer->winsys = g_slice_new0 (CoglRendererEGL);
egl_renderer = renderer->winsys;
egl_renderer->platform_vtable = &_cogl_winsys_egl_vtable;
egl_renderer->edpy = eglGetDisplay (EGL_DEFAULT_DISPLAY);
if (!_cogl_winsys_egl_renderer_connect_common (renderer, error))
goto error;
return TRUE;
error:
_cogl_winsys_renderer_disconnect (renderer);
return FALSE;
}
static CoglBool
_cogl_winsys_egl_context_created (CoglDisplay *display,
GError **error)
{
CoglRenderer *renderer = display->renderer;
CoglRendererEGL *egl_renderer = renderer->winsys;
CoglDisplayEGL *egl_display = display->winsys;
CoglDisplayNull *null_display = egl_display->platform;
const char *error_message;
egl_display->egl_surface =
eglCreateWindowSurface (egl_renderer->edpy,
egl_display->egl_config,
(NativeWindowType) NULL,
NULL);
if (egl_display->egl_surface == EGL_NO_SURFACE)
{
error_message = "Unable to create EGL window surface";
goto fail;
}
if (!_cogl_winsys_egl_make_current (display,
egl_display->egl_surface,
egl_display->egl_surface,
egl_display->egl_context))
{
error_message = "Unable to eglMakeCurrent with egl surface";
goto fail;
}
eglQuerySurface (egl_renderer->edpy,
egl_display->egl_surface,
EGL_WIDTH,
&null_display->egl_surface_width);
eglQuerySurface (egl_renderer->edpy,
egl_display->egl_surface,
EGL_HEIGHT,
&null_display->egl_surface_height);
return TRUE;
fail:
g_set_error (error, COGL_WINSYS_ERROR,
COGL_WINSYS_ERROR_CREATE_CONTEXT,
"%s", error_message);
return FALSE;
}
static CoglBool
_cogl_winsys_egl_display_setup (CoglDisplay *display,
GError **error)
{
CoglDisplayEGL *egl_display = display->winsys;
CoglDisplayNull *null_display;
null_display = g_slice_new0 (CoglDisplayNull);
egl_display->platform = null_display;
return TRUE;
}
static void
_cogl_winsys_egl_display_destroy (CoglDisplay *display)
{
CoglDisplayEGL *egl_display = display->winsys;
g_slice_free (CoglDisplayNull, egl_display->platform);
}
static void
_cogl_winsys_egl_cleanup_context (CoglDisplay *display)
{
CoglRenderer *renderer = display->renderer;
CoglRendererEGL *egl_renderer = renderer->winsys;
CoglDisplayEGL *egl_display = display->winsys;
if (egl_display->egl_surface != EGL_NO_SURFACE)
{
eglDestroySurface (egl_renderer->edpy, egl_display->egl_surface);
egl_display->egl_surface = EGL_NO_SURFACE;
}
}
static CoglBool
_cogl_winsys_egl_onscreen_init (CoglOnscreen *onscreen,
EGLConfig egl_config,
GError **error)
{
CoglFramebuffer *framebuffer = COGL_FRAMEBUFFER (onscreen);
CoglContext *context = framebuffer->context;
CoglDisplay *display = context->display;
CoglDisplayEGL *egl_display = display->winsys;
CoglDisplayNull *null_display = egl_display->platform;
CoglOnscreenEGL *egl_onscreen = onscreen->winsys;
if (null_display->have_onscreen)
{
g_set_error (error, COGL_WINSYS_ERROR,
COGL_WINSYS_ERROR_CREATE_ONSCREEN,
"EGL platform only supports a single onscreen window");
return FALSE;
}
egl_onscreen->egl_surface = egl_display->egl_surface;
_cogl_framebuffer_winsys_update_size (framebuffer,
null_display->egl_surface_width,
null_display->egl_surface_height);
null_display->have_onscreen = TRUE;
return TRUE;
}
static void
_cogl_winsys_egl_onscreen_deinit (CoglOnscreen *onscreen)
{
CoglFramebuffer *framebuffer = COGL_FRAMEBUFFER (onscreen);
CoglContext *context = framebuffer->context;
CoglDisplay *display = context->display;
CoglDisplayEGL *egl_display = display->winsys;
CoglDisplayNull *null_display = egl_display->platform;
null_display->have_onscreen = FALSE;
}
static const CoglWinsysEGLVtable
_cogl_winsys_egl_vtable =
{
.display_setup = _cogl_winsys_egl_display_setup,
.display_destroy = _cogl_winsys_egl_display_destroy,
.context_created = _cogl_winsys_egl_context_created,
.cleanup_context = _cogl_winsys_egl_cleanup_context,
.onscreen_init = _cogl_winsys_egl_onscreen_init,
.onscreen_deinit = _cogl_winsys_egl_onscreen_deinit
};
const CoglWinsysVtable *
_cogl_winsys_egl_null_get_vtable (void)
{
static CoglBool vtable_inited = FALSE;
static CoglWinsysVtable vtable;
if (!vtable_inited)
{
/* The EGL_NULL winsys is a subclass of the EGL winsys so we
start by copying its vtable */
vtable = *_cogl_winsys_egl_get_vtable ();
vtable.id = COGL_WINSYS_ID_EGL_NULL;
vtable.name = "EGL_NULL";
vtable.renderer_connect = _cogl_winsys_renderer_connect;
vtable.renderer_disconnect = _cogl_winsys_renderer_disconnect;
vtable_inited = TRUE;
}
return &vtable;
}