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/* cairo - a vector graphics library with display and print output
*
* Copyright © 2009 Eric Anholt
* Copyright © 2009 Chris Wilson
* Copyright © 2005 Red Hat, Inc
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
* The Original Code is the cairo graphics library.
*
* The Initial Developer of the Original Code is Red Hat, Inc.
*
* Contributor(s):
* Carl Worth <cworth@cworth.org>
* Chris Wilson <chris@chris-wilson.co.uk>
*/
#include "cairoint.h"
#include "cairo-gl-private.h"
#include "cairo-error-private.h"
typedef struct _cairo_egl_context {
cairo_gl_context_t base;
EGLDisplay display;
EGLContext context;
EGLSurface dummy_surface;
EGLContext previous_context;
EGLSurface previous_surface;
} cairo_egl_context_t;
typedef struct _cairo_egl_surface {
cairo_gl_surface_t base;
EGLSurface egl;
} cairo_egl_surface_t;
static cairo_bool_t
_context_acquisition_changed_egl_state (cairo_egl_context_t *ctx,
EGLSurface current_surface)
{
return ctx->previous_context != ctx->context ||
ctx->previous_surface != current_surface;
}
static EGLSurface
_egl_get_current_surface (cairo_egl_context_t *ctx)
{
if (ctx->base.current_target == NULL ||
_cairo_gl_surface_is_texture (ctx->base.current_target)) {
return ctx->dummy_surface;
}
return ((cairo_egl_surface_t *) ctx->base.current_target)->egl;
}
static void
_egl_query_current_state (cairo_egl_context_t *ctx)
{
ctx->previous_surface = eglGetCurrentSurface (EGL_DRAW);
ctx->previous_context = eglGetCurrentContext ();
/* If any of the values were none, assume they are all none. Not all
drivers seem well behaved when it comes to using these values across
multiple threads. */
if (ctx->previous_surface == EGL_NO_SURFACE ||
ctx->previous_context == EGL_NO_CONTEXT) {
ctx->previous_surface = EGL_NO_SURFACE;
ctx->previous_context = EGL_NO_CONTEXT;
}
}
static void
_egl_acquire (void *abstract_ctx)
{
cairo_egl_context_t *ctx = abstract_ctx;
EGLSurface current_surface = _egl_get_current_surface (ctx);
_egl_query_current_state (ctx);
if (!_context_acquisition_changed_egl_state (ctx, current_surface))
return;
eglMakeCurrent (ctx->display,
current_surface, current_surface, ctx->context);
}
static void
_egl_release (void *abstract_ctx)
{
cairo_egl_context_t *ctx = abstract_ctx;
if (!ctx->base.thread_aware ||
!_context_acquisition_changed_egl_state (ctx,
_egl_get_current_surface (ctx))) {
return;
}
eglMakeCurrent (ctx->display,
EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
}
static void
_egl_make_current (void *abstract_ctx,
cairo_gl_surface_t *abstract_surface)
{
cairo_egl_context_t *ctx = abstract_ctx;
cairo_egl_surface_t *surface = (cairo_egl_surface_t *) abstract_surface;
eglMakeCurrent(ctx->display, surface->egl, surface->egl, ctx->context);
}
static void
_egl_swap_buffers (void *abstract_ctx,
cairo_gl_surface_t *abstract_surface)
{
cairo_egl_context_t *ctx = abstract_ctx;
cairo_egl_surface_t *surface = (cairo_egl_surface_t *) abstract_surface;
eglSwapBuffers (ctx->display, surface->egl);
}
static void
_egl_destroy (void *abstract_ctx)
{
cairo_egl_context_t *ctx = abstract_ctx;
eglMakeCurrent (ctx->display,
EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
if (ctx->dummy_surface != EGL_NO_SURFACE)
eglDestroySurface (ctx->display, ctx->dummy_surface);
}
static cairo_bool_t
_egl_make_current_surfaceless(cairo_egl_context_t *ctx)
{
const char *extensions;
extensions = eglQueryString(ctx->display, EGL_EXTENSIONS);
if (strstr(extensions, "EGL_KHR_surfaceless_context") == NULL &&
strstr(extensions, "EGL_KHR_surfaceless_opengl") == NULL)
return FALSE;
if (!eglMakeCurrent(ctx->display,
EGL_NO_SURFACE, EGL_NO_SURFACE, ctx->context))
return FALSE;
return TRUE;
}
cairo_device_t *
cairo_egl_device_create (EGLDisplay dpy, EGLContext egl)
{
cairo_egl_context_t *ctx;
cairo_status_t status;
int attribs[] = {
EGL_WIDTH, 1,
EGL_HEIGHT, 1,
EGL_NONE,
};
EGLConfig config;
EGLint numConfigs;
ctx = calloc (1, sizeof (cairo_egl_context_t));
if (unlikely (ctx == NULL))
return _cairo_gl_context_create_in_error (CAIRO_STATUS_NO_MEMORY);
ctx->display = dpy;
ctx->context = egl;
ctx->base.acquire = _egl_acquire;
ctx->base.release = _egl_release;
ctx->base.make_current = _egl_make_current;
ctx->base.swap_buffers = _egl_swap_buffers;
ctx->base.destroy = _egl_destroy;
/* We are about the change the current state of EGL, so we should
* query the pre-existing surface now instead of later. */
_egl_query_current_state (ctx);
if (!_egl_make_current_surfaceless (ctx)) {
/* Fall back to dummy surface, meh. */
EGLint config_attribs[] = {
EGL_CONFIG_ID, 0,
EGL_NONE
};
/*
* In order to be able to make an egl context current when using a
* pbuffer surface, that surface must have been created with a config
* that is compatible with the context config. For Mesa, this means
* that the configs must be the same.
*/
eglQueryContext (dpy, egl, EGL_CONFIG_ID, &config_attribs[1]);
eglChooseConfig (dpy, config_attribs, &config, 1, &numConfigs);
ctx->dummy_surface = eglCreatePbufferSurface (dpy, config, attribs);
if (ctx->dummy_surface == NULL) {
free (ctx);
return _cairo_gl_context_create_in_error (CAIRO_STATUS_NO_MEMORY);
}
if (!eglMakeCurrent (dpy, ctx->dummy_surface, ctx->dummy_surface, egl)) {
free (ctx);
return _cairo_gl_context_create_in_error (CAIRO_STATUS_NO_MEMORY);
}
}
status = _cairo_gl_dispatch_init (&ctx->base.dispatch, eglGetProcAddress);
if (unlikely (status)) {
free (ctx);
return _cairo_gl_context_create_in_error (status);
}
status = _cairo_gl_context_init (&ctx->base);
if (unlikely (status)) {
if (ctx->dummy_surface != EGL_NO_SURFACE)
eglDestroySurface (dpy, ctx->dummy_surface);
free (ctx);
return _cairo_gl_context_create_in_error (status);
}
/* Tune the default VBO size to reduce overhead on embedded devices.
* This smaller size means that flushing needs to be done more often,
* but it is less demanding of scarce memory on embedded devices.
*/
ctx->base.vbo_size = 16*1024;
eglMakeCurrent (dpy, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
return &ctx->base.base;
}
cairo_surface_t *
cairo_gl_surface_create_for_egl (cairo_device_t *device,
EGLSurface egl,
int width,
int height)
{
cairo_egl_surface_t *surface;
if (unlikely (device->status))
return _cairo_surface_create_in_error (device->status);
if (device->backend->type != CAIRO_DEVICE_TYPE_GL)
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_SURFACE_TYPE_MISMATCH));
if (width <= 0 || height <= 0)
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_INVALID_SIZE));
surface = calloc (1, sizeof (cairo_egl_surface_t));
if (unlikely (surface == NULL))
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));
_cairo_gl_surface_init (device, &surface->base,
CAIRO_CONTENT_COLOR_ALPHA, width, height);
surface->egl = egl;
return &surface->base.base;
}
static cairo_bool_t is_egl_device (cairo_device_t *device)
{
return (device->backend != NULL &&
device->backend->type == CAIRO_DEVICE_TYPE_GL);
}
static cairo_egl_context_t *to_egl_context (cairo_device_t *device)
{
return (cairo_egl_context_t *) device;
}
EGLDisplay
cairo_egl_device_get_display (cairo_device_t *device)
{
if (! is_egl_device (device)) {
_cairo_error_throw (CAIRO_STATUS_DEVICE_TYPE_MISMATCH);
return EGL_NO_DISPLAY;
}
return to_egl_context (device)->display;
}
cairo_public EGLContext
cairo_egl_device_get_context (cairo_device_t *device)
{
if (! is_egl_device (device)) {
_cairo_error_throw (CAIRO_STATUS_DEVICE_TYPE_MISMATCH);
return EGL_NO_CONTEXT;
}
return to_egl_context (device)->context;
}