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/* cairo - a vector graphics library with display and print output
*
* Copyright © 2010 Linaro Limited
*
* 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.
*
* Contributor(s):
* Alexandros Frantzis <alexandros.frantzis@linaro.org>
* Heiko Lewin <heiko.lewin@gmx.de>
*/
#include "cairoint.h"
#include "cairo-gl-private.h"
#include <errno.h>
int
_cairo_gl_get_version (void)
{
int major, minor;
const char *version = (const char *) glGetString (GL_VERSION);
const char *dot = version == NULL ? NULL : strchr (version, '.');
const char *major_start = dot;
/* Sanity check */
if (dot == NULL || dot == version || *(dot + 1) == '\0') {
major = 0;
minor = 0;
} else {
/* Find the start of the major version in the string */
while (major_start > version && *major_start != ' ')
--major_start;
major = strtol (major_start, NULL, 10);
minor = strtol (dot + 1, NULL, 10);
}
return CAIRO_GL_VERSION_ENCODE (major, minor);
}
cairo_gl_flavor_t
_cairo_gl_degrade_flavor_by_build_features (cairo_gl_flavor_t flavor) {
switch(flavor) {
case CAIRO_GL_FLAVOR_DESKTOP:
#if CAIRO_HAS_GL_SURFACE
return CAIRO_GL_FLAVOR_DESKTOP;
#else
return CAIRO_GL_FLAVOR_NONE;
#endif
case CAIRO_GL_FLAVOR_ES3:
#if CAIRO_HAS_GLESV3_SURFACE
return CAIRO_GL_FLAVOR_ES3;
#else
/* intentional fall through: degrade to GLESv2 if GLESv3-surfaces are not available */
#endif
case CAIRO_GL_FLAVOR_ES2:
#if CAIRO_HAS_GLESV2_SURFACE
return CAIRO_GL_FLAVOR_ES2;
#else
/* intentional fall through: no OpenGL in first place or no surfaces for it's version */
#endif
default:
return CAIRO_GL_FLAVOR_NONE;
}
}
cairo_gl_flavor_t
_cairo_gl_get_flavor (void)
{
const char *version = (const char *) glGetString (GL_VERSION);
cairo_gl_flavor_t flavor;
if (version == NULL) {
flavor = CAIRO_GL_FLAVOR_NONE;
} else if (strstr (version, "OpenGL ES 3") != NULL) {
flavor = CAIRO_GL_FLAVOR_ES3;
} else if (strstr (version, "OpenGL ES 2") != NULL) {
flavor = CAIRO_GL_FLAVOR_ES2;
} else {
flavor = CAIRO_GL_FLAVOR_DESKTOP;
}
return _cairo_gl_degrade_flavor_by_build_features(flavor);
}
unsigned long
_cairo_gl_get_vbo_size (void)
{
unsigned long vbo_size;
const char *env = getenv ("CAIRO_GL_VBO_SIZE");
if (env == NULL) {
vbo_size = CAIRO_GL_VBO_SIZE_DEFAULT;
} else {
errno = 0;
vbo_size = strtol (env, NULL, 10);
assert (errno == 0);
assert (vbo_size > 0);
}
return vbo_size;
}
cairo_bool_t
_cairo_gl_has_extension (const char *ext)
{
const char *extensions = (const char *) glGetString (GL_EXTENSIONS);
size_t len = strlen (ext);
const char *ext_ptr = extensions;
if (unlikely (ext_ptr == NULL))
return 0;
while ((ext_ptr = strstr (ext_ptr, ext)) != NULL) {
if (ext_ptr[len] == ' ' || ext_ptr[len] == '\0')
break;
ext_ptr += len;
}
return (ext_ptr != NULL);
}