mutter/cogl/winsys/cogl-winsys-egl-private.h
Neil Roberts 52a646abc5 Use the EGL_KHR_surfacless_context extension
The surfaceless context extension can be used to bind a context
without a surface. We can use this to avoid creating a dummy surface
when the CoglContext is first created. Otherwise we have to have the
dummy surface so that we can bind it before the first onscreen is
created.

The main awkward part of this patch is that theoretically according to
the GL and GLES spec if you first bind a context without a surface
then the default state for glDrawBuffers is GL_NONE instead of
GL_BACK. In practice Mesa doesn't seem to do this but we need to be
robust against a GL implementation that does. Therefore we track when
the CoglContext is first used with a CoglOnscreen and force the
glDrawBuffers state to be GL_BACK.

There is a further awkward part in that GLES2 doesn't actually have a
glDrawBuffers state but GLES3 does. GLES3 also defaults to GL_NONE in
this case so if GLES3 is available then we have to be sure to set the
state to GL_BACK. As far as I can tell that actually makes GLES3
incompatible with GLES2 because in theory if the application is not
aware of GLES3 then it should be able to assume the draw buffer is
always GL_BACK.

Reviewed-by: Robert Bragg <robert.bragg@intel.com>
(cherry picked from commit e5f28f1e75db9bdc4f2688f420a74f908f96cf76)

Conflicts:
	cogl/winsys/cogl-winsys-egl-kms.c
	cogl/winsys/cogl-winsys-egl-x11.c
2014-06-17 13:31:03 +01:00

204 lines
5.9 KiB
C

/*
* Cogl
*
* A Low Level GPU Graphics and Utilities API
*
* Copyright (C) 2011 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*
*/
#ifndef __COGL_WINSYS_EGL_PRIVATE_H
#define __COGL_WINSYS_EGL_PRIVATE_H
#include "cogl-defines.h"
#include "cogl-winsys-private.h"
#include "cogl-context.h"
#include "cogl-context-private.h"
#include "cogl-framebuffer-private.h"
/* XXX: depending on what version of Mesa you have then
* eglQueryWaylandBuffer may take a wl_buffer or wl_resource argument
* and the EGL header will only forward declare the corresponding
* type.
*
* The use of wl_buffer has been deprecated and so internally we
* assume that eglQueryWaylandBuffer takes a wl_resource but for
* compatibility we forward declare wl_resource in case we are
* building with EGL headers that still use wl_buffer.
*
* Placing the forward declaration here means it comes before we
* #include cogl-winsys-egl-feature-functions.h bellow which
* declares lots of function pointers for accessing EGL extensions
* and cogl-winsys-egl.c will include this header before it also
* includes cogl-winsys-egl-feature-functions.h that may depend
* on this type.
*/
#ifdef EGL_WL_bind_wayland_display
struct wl_resource;
#endif
typedef struct _CoglWinsysEGLVtable
{
CoglBool
(* display_setup) (CoglDisplay *display,
CoglError **error);
void
(* display_destroy) (CoglDisplay *display);
CoglBool
(* context_created) (CoglDisplay *display,
CoglError **error);
void
(* cleanup_context) (CoglDisplay *display);
CoglBool
(* context_init) (CoglContext *context, CoglError **error);
void
(* context_deinit) (CoglContext *context);
CoglBool
(* onscreen_init) (CoglOnscreen *onscreen,
EGLConfig config,
CoglError **error);
void
(* onscreen_deinit) (CoglOnscreen *onscreen);
int
(* add_config_attributes) (CoglDisplay *display,
CoglFramebufferConfig *config,
EGLint *attributes);
} CoglWinsysEGLVtable;
typedef enum _CoglEGLWinsysFeature
{
COGL_EGL_WINSYS_FEATURE_SWAP_REGION =1L<<0,
COGL_EGL_WINSYS_FEATURE_EGL_IMAGE_FROM_X11_PIXMAP =1L<<1,
COGL_EGL_WINSYS_FEATURE_EGL_IMAGE_FROM_WAYLAND_BUFFER =1L<<2,
COGL_EGL_WINSYS_FEATURE_CREATE_CONTEXT =1L<<3,
COGL_EGL_WINSYS_FEATURE_BUFFER_AGE =1L<<4,
COGL_EGL_WINSYS_FEATURE_FENCE_SYNC =1L<<5,
COGL_EGL_WINSYS_FEATURE_SURFACELESS_CONTEXT =1L<<6
} CoglEGLWinsysFeature;
typedef struct _CoglRendererEGL
{
CoglEGLWinsysFeature private_features;
EGLDisplay edpy;
EGLint egl_version_major;
EGLint egl_version_minor;
CoglClosure *resize_notify_idle;
/* Data specific to the EGL platform */
void *platform;
/* vtable for platform specific parts */
const CoglWinsysEGLVtable *platform_vtable;
/* Function pointers for EGL specific extensions */
#define COGL_WINSYS_FEATURE_BEGIN(a, b, c, d)
#define COGL_WINSYS_FEATURE_FUNCTION(ret, name, args) \
ret (APIENTRY * pf_ ## name) args;
#define COGL_WINSYS_FEATURE_END()
#include "cogl-winsys-egl-feature-functions.h"
#undef COGL_WINSYS_FEATURE_BEGIN
#undef COGL_WINSYS_FEATURE_FUNCTION
#undef COGL_WINSYS_FEATURE_END
} CoglRendererEGL;
typedef struct _CoglDisplayEGL
{
EGLContext egl_context;
EGLSurface dummy_surface;
EGLSurface egl_surface;
EGLConfig egl_config;
CoglBool found_egl_config;
EGLSurface current_read_surface;
EGLSurface current_draw_surface;
EGLContext current_context;
/* Platform specific display data */
void *platform;
} CoglDisplayEGL;
typedef struct _CoglContextEGL
{
EGLSurface saved_draw_surface;
EGLSurface saved_read_surface;
} CoglContextEGL;
typedef struct _CoglOnscreenEGL
{
EGLSurface egl_surface;
CoglBool pending_resize_notify;
/* Platform specific data */
void *platform;
} CoglOnscreenEGL;
const CoglWinsysVtable *
_cogl_winsys_egl_get_vtable (void);
EGLBoolean
_cogl_winsys_egl_make_current (CoglDisplay *display,
EGLSurface draw,
EGLSurface read,
EGLContext context);
#ifdef EGL_KHR_image_base
EGLImageKHR
_cogl_egl_create_image (CoglContext *ctx,
EGLenum target,
EGLClientBuffer buffer,
const EGLint *attribs);
void
_cogl_egl_destroy_image (CoglContext *ctx,
EGLImageKHR image);
#endif
#ifdef EGL_WL_bind_wayland_display
CoglBool
_cogl_egl_query_wayland_buffer (CoglContext *ctx,
struct wl_resource *buffer,
int attribute,
int *value);
#endif
CoglBool
_cogl_winsys_egl_renderer_connect_common (CoglRenderer *renderer,
CoglError **error);
#endif /* __COGL_WINSYS_EGL_PRIVATE_H */