mutter/cogl/cogl-feature-private.c
Robert Bragg be15bf75e4 Add internal _cogl_get_proc_address
This adds an internal _cogl_get_proc_address that doesn't need a
CoglContext. This will enable us to check driver features earlier.
2011-06-01 20:44:41 +01:00

142 lines
4.4 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2009 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/>.
*
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "cogl.h"
#include "cogl-context-private.h"
#include "cogl-feature-private.h"
gboolean
_cogl_feature_check (const CoglWinsysVtable *winsys,
const char *driver_prefix,
const CoglFeatureData *data,
unsigned int gl_major,
unsigned int gl_minor,
const char *extensions_string,
void *function_table)
{
const char *suffix = NULL;
int func_num;
/* First check whether the functions should be directly provided by
GL */
if (COGL_CHECK_GL_VERSION (gl_major, gl_minor,
data->min_gl_major, data->min_gl_minor))
suffix = "";
else
{
/* Otherwise try all of the extensions */
const char *namespace, *namespace_suffix;
unsigned int namespace_len;
for (namespace = data->namespaces;
*namespace;
namespace += strlen (namespace) + 1)
{
const char *extension;
GString *full_extension_name = g_string_new ("");
/* If the namespace part contains a ':' then the suffix for
the function names is different from the name space */
if ((namespace_suffix = strchr (namespace, ':')))
{
namespace_len = namespace_suffix - namespace;
namespace_suffix++;
}
else
{
namespace_len = strlen (namespace);
namespace_suffix = namespace;
}
for (extension = data->extension_names;
*extension;
extension += strlen (extension) + 1)
{
g_string_assign (full_extension_name, driver_prefix);
g_string_append_c (full_extension_name, '_');
g_string_append_len (full_extension_name,
namespace, namespace_len);
g_string_append_c (full_extension_name, '_');
g_string_append (full_extension_name, extension);
if (!_cogl_check_extension (full_extension_name->str,
extensions_string))
break;
}
g_string_free (full_extension_name, TRUE);
/* If we found all of the extensions with this namespace
then use it as the suffix */
if (*extension == '\0')
{
suffix = namespace_suffix;
break;
}
}
}
/* If we couldn't find anything that provides the functions then
give up */
if (suffix == NULL)
goto error;
/* Try to get all of the entry points */
for (func_num = 0; data->functions[func_num].name; func_num++)
{
void *func;
char *full_function_name;
full_function_name = g_strconcat (data->functions[func_num].name,
suffix, NULL);
func = _cogl_get_proc_address (winsys, full_function_name);
g_free (full_function_name);
if (func == NULL)
goto error;
/* Set the function pointer in the context */
*(void **) ((guint8 *) function_table +
data->functions[func_num].pointer_offset) = func;
}
return TRUE;
/* If the extension isn't found or one of the functions wasn't found
* then set all of the functions pointers to NULL so Cogl can safely
* do feature testing by just looking at the function pointers */
error:
for (func_num = 0; data->functions[func_num].name; func_num++)
*(void **) ((guint8 *) function_table +
data->functions[func_num].pointer_offset) = NULL;
return FALSE;
}