mutter/cogl/driver/gl/cogl.c
Robert Bragg 7571cc1923 cogl: expose the semantic differences of gl/gles2 npot textures
This adds three new feature flags COGL_FEATURE_TEXTURE_NPOT_BASIC,
COGL_FEATURE_TEXTURE_NPOT_MIPMAP and COGL_FEATURE_TEXTURE_NPOT_REPEAT
that can tell you if your hardware supports non power of two textures,
npot textures + mipmaps and npot textures + wrap modes other than
CLAMP_TO_EDGE.

The pre-existing COGL_FEATURE_TEXTURE_NPOT feature implies all of the
above.

By default GLES 2 core supports npot textures but mipmaps and repeat
modes can only be used with power of two textures. This patch also makes
GLES check for the GL_OES_texture_npot extension to determine if mipmaps
and repeating are supported with npot textures.
2010-07-07 13:26:41 +01:00

238 lines
7.3 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2007,2008,2009 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-internal.h"
#include "cogl-context.h"
#include "cogl-feature-private.h"
#ifdef HAVE_CLUTTER_OSX
static gboolean
really_enable_npot (void)
{
/* OSX backend + ATI Radeon X1600 + NPOT texture + GL_REPEAT seems to crash
* http://bugzilla.openedhand.com/show_bug.cgi?id=929
*
* Temporary workaround until post 0.8 we rejig the features set up a
* little to allow the backend to overide.
*/
const char *gl_renderer;
const char *env_string;
/* Regardless of hardware, allow user to decide. */
env_string = g_getenv ("COGL_ENABLE_NPOT");
if (env_string != NULL)
return env_string[0] == '1';
gl_renderer = (char*)glGetString (GL_RENDERER);
if (strstr (gl_renderer, "ATI Radeon X1600") != NULL)
return FALSE;
return TRUE;
}
#endif
static gboolean
_cogl_get_gl_version (int *major_out, int *minor_out)
{
const char *version_string, *major_end, *minor_end;
int major = 0, minor = 0;
/* Get the OpenGL version number */
if ((version_string = (const char *) glGetString (GL_VERSION)) == NULL)
return FALSE;
/* Extract the major number */
for (major_end = version_string; *major_end >= '0'
&& *major_end <= '9'; major_end++)
major = (major * 10) + *major_end - '0';
/* If there were no digits or the major number isn't followed by a
dot then it is invalid */
if (major_end == version_string || *major_end != '.')
return FALSE;
/* Extract the minor number */
for (minor_end = major_end + 1; *minor_end >= '0'
&& *minor_end <= '9'; minor_end++)
minor = (minor * 10) + *minor_end - '0';
/* If there were no digits or there is an unexpected character then
it is invalid */
if (minor_end == major_end + 1
|| (*minor_end && *minor_end != ' ' && *minor_end != '.'))
return FALSE;
*major_out = major;
*minor_out = minor;
return TRUE;
}
gboolean
_cogl_check_driver_valid (GError **error)
{
int major, minor;
const char *gl_extensions;
if (!_cogl_get_gl_version (&major, &minor))
{
g_set_error (error,
COGL_DRIVER_ERROR,
COGL_DRIVER_ERROR_UNKNOWN_VERSION,
"The OpenGL version could not be determined");
return FALSE;
}
/* GL 1.3 supports all of the required functionality in core */
if (COGL_CHECK_GL_VERSION (major, minor, 1, 3))
return TRUE;
gl_extensions = (const char*) glGetString (GL_EXTENSIONS);
/* OpenGL 1.2 is only supported if we have the multitexturing
extension */
if (!_cogl_check_extension ("GL_ARB_multitexture", gl_extensions))
{
g_set_error (error,
COGL_DRIVER_ERROR,
COGL_DRIVER_ERROR_INVALID_VERSION,
"The OpenGL driver is missing "
"the GL_ARB_multitexture extension");
return FALSE;
}
/* OpenGL 1.2 is required */
if (!COGL_CHECK_GL_VERSION (major, minor, 1, 2))
{
g_set_error (error,
COGL_DRIVER_ERROR,
COGL_DRIVER_ERROR_INVALID_VERSION,
"The OpenGL version of your driver (%i.%i) "
"is not compatible with Cogl",
major, minor);
return FALSE;
}
return TRUE;
}
/* Define a set of arrays containing the functions required from GL
for each feature */
#define COGL_FEATURE_BEGIN(name, min_gl_major, min_gl_minor, \
namespaces, extension_names, \
feature_flags, feature_flags_private) \
static const CoglFeatureFunction cogl_feature_ ## name ## _funcs[] = {
#define COGL_FEATURE_FUNCTION(ret, name, args) \
{ G_STRINGIFY (name), G_STRUCT_OFFSET (CoglContext, drv.pf_ ## name) },
#define COGL_FEATURE_END() \
{ NULL, 0 }, \
};
#include "cogl-feature-functions.h"
/* Define an array of features */
#undef COGL_FEATURE_BEGIN
#define COGL_FEATURE_BEGIN(name, min_gl_major, min_gl_minor, \
namespaces, extension_names, \
feature_flags, feature_flags_private) \
{ min_gl_major, min_gl_minor, namespaces, \
extension_names, feature_flags, feature_flags_private, \
cogl_feature_ ## name ## _funcs },
#undef COGL_FEATURE_FUNCTION
#define COGL_FEATURE_FUNCTION(ret, name, args)
#undef COGL_FEATURE_END
#define COGL_FEATURE_END()
static const CoglFeatureData cogl_feature_data[] =
{
#include "cogl-feature-functions.h"
};
void
_cogl_features_init (void)
{
CoglFeatureFlags flags = 0;
CoglFeatureFlagsPrivate flags_private = 0;
const char *gl_extensions;
GLint max_clip_planes = 0;
GLint num_stencil_bits = 0;
int gl_major = 0, gl_minor = 0;
int i;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
_cogl_get_gl_version (&gl_major, &gl_minor);
flags = (COGL_FEATURE_TEXTURE_READ_PIXELS
| COGL_FEATURE_UNSIGNED_INT_INDICES);
gl_extensions = (const char*) glGetString (GL_EXTENSIONS);
if (COGL_CHECK_GL_VERSION (gl_major, gl_minor, 2, 0) ||
_cogl_check_extension ("GL_ARB_texture_non_power_of_two", gl_extensions))
{
#ifdef HAVE_CLUTTER_OSX
if (really_enable_npot ())
#endif
flags |= COGL_FEATURE_TEXTURE_NPOT
| COGL_FEATURE_TEXTURE_NPOT_BASIC
| COGL_FEATURE_TEXTURE_NPOT_MIPMAP
| COGL_FEATURE_TEXTURE_NPOT_REPEAT;
}
#ifdef GL_YCBCR_MESA
if (_cogl_check_extension ("GL_MESA_ycbcr_texture", gl_extensions))
{
flags |= COGL_FEATURE_TEXTURE_YUV;
}
#endif
GE( glGetIntegerv (GL_STENCIL_BITS, &num_stencil_bits) );
/* We need at least three stencil bits to combine clips */
if (num_stencil_bits > 2)
flags |= COGL_FEATURE_STENCIL_BUFFER;
GE( glGetIntegerv (GL_MAX_CLIP_PLANES, &max_clip_planes) );
if (max_clip_planes >= 4)
flags |= COGL_FEATURE_FOUR_CLIP_PLANES;
for (i = 0; i < G_N_ELEMENTS (cogl_feature_data); i++)
if (_cogl_feature_check ("GL", cogl_feature_data + i,
gl_major, gl_minor,
gl_extensions))
{
flags |= cogl_feature_data[i].feature_flags;
flags_private |= cogl_feature_data[i].feature_flags_private;
}
/* Cache features */
ctx->feature_flags = flags;
ctx->feature_flags_private = flags_private;
ctx->features_cached = TRUE;
}