mutter/cogl/driver/gles/cogl-gles.c
Neil Roberts df77e8565e Don't use eglGetProcAddress to retrieve core functions
According to the EGL spec, eglGetProcAddress should only be used to
retrieve extension functions. It also says that returning non-NULL
does not mean the extension is available so you could interpret this
as saying that the function is allowed to return garbage for core
functions. This seems to happen at least for the Android
implementation of EGL.

To workaround this the winsys's are now passed down a flag to say
whether the function is from the core API. This information is already
in the gl-prototypes headers as the minimum core GL version and as a
pair of flags to specify whether it is available in core GLES1 and
GLES2. If the function is in core the EGL winsys will now avoid using
eglGetProcAddress and always fallback to querying the library directly
with the GModule API.

The GLX winsys is left alone because glXGetProcAddress apparently
supports querying core API and extension functions.

The WGL winsys could ideally be changed because wglGetProcAddress
should also only be used for extension functions but the situation is
slightly different because WGL considers anything from GL > 1.1 to be
an extension so it would need a bit more information to determine
whether to query the function directly from the library.

The SDL winsys is also left alone because it's not as easy to portably
determine which GL library SDL has chosen to load in order to resolve
the symbols directly.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit 72089730ad06ccdd38a344279a893965ae68cec1)

  Since we aren't able to break API on the 1.12 branch
  cogl_get_proc_address is still supported but isn't easily able to
  determine whether the given name corresponds to a core symbol or
  not.  For now we just assume the symbol being queried isn't part
  of the core GL api and update the documentation accordingly.
2012-08-06 14:27:45 +01:00

316 lines
10 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-internal.h"
#include "cogl-context-private.h"
#include "cogl-feature-private.h"
#include "cogl-renderer-private.h"
#include "cogl-private.h"
static CoglBool
_cogl_driver_pixel_format_from_gl_internal (CoglContext *context,
GLenum gl_int_format,
CoglPixelFormat *out_format)
{
return TRUE;
}
static CoglPixelFormat
_cogl_driver_pixel_format_to_gl (CoglContext *context,
CoglPixelFormat format,
GLenum *out_glintformat,
GLenum *out_glformat,
GLenum *out_gltype)
{
CoglPixelFormat required_format;
GLenum glintformat;
GLenum glformat = 0;
GLenum gltype;
required_format = format;
/* Find GL equivalents */
switch (format)
{
case COGL_PIXEL_FORMAT_A_8:
glintformat = GL_ALPHA;
glformat = GL_ALPHA;
gltype = GL_UNSIGNED_BYTE;
break;
case COGL_PIXEL_FORMAT_G_8:
glintformat = GL_LUMINANCE;
glformat = GL_LUMINANCE;
gltype = GL_UNSIGNED_BYTE;
break;
case COGL_PIXEL_FORMAT_BGRA_8888:
case COGL_PIXEL_FORMAT_BGRA_8888_PRE:
/* There is an extension to support this format */
if ((context->private_feature_flags &
COGL_PRIVATE_FEATURE_TEXTURE_FORMAT_BGRA8888))
{
/* For some reason the extension says you have to specify
BGRA for the internal format too */
glintformat = GL_BGRA_EXT;
glformat = GL_BGRA_EXT;
gltype = GL_UNSIGNED_BYTE;
required_format = format;
break;
}
/* flow through */
/* Just one 24-bit ordering supported */
case COGL_PIXEL_FORMAT_RGB_888:
case COGL_PIXEL_FORMAT_BGR_888:
glintformat = GL_RGB;
glformat = GL_RGB;
gltype = GL_UNSIGNED_BYTE;
required_format = COGL_PIXEL_FORMAT_RGB_888;
break;
/* Just one 32-bit ordering supported */
case COGL_PIXEL_FORMAT_RGBA_8888:
case COGL_PIXEL_FORMAT_RGBA_8888_PRE:
case COGL_PIXEL_FORMAT_ARGB_8888:
case COGL_PIXEL_FORMAT_ARGB_8888_PRE:
case COGL_PIXEL_FORMAT_ABGR_8888:
case COGL_PIXEL_FORMAT_ABGR_8888_PRE:
case COGL_PIXEL_FORMAT_RGBA_1010102:
case COGL_PIXEL_FORMAT_RGBA_1010102_PRE:
case COGL_PIXEL_FORMAT_BGRA_1010102:
case COGL_PIXEL_FORMAT_BGRA_1010102_PRE:
case COGL_PIXEL_FORMAT_ABGR_2101010:
case COGL_PIXEL_FORMAT_ABGR_2101010_PRE:
case COGL_PIXEL_FORMAT_ARGB_2101010:
case COGL_PIXEL_FORMAT_ARGB_2101010_PRE:
glintformat = GL_RGBA;
glformat = GL_RGBA;
gltype = GL_UNSIGNED_BYTE;
required_format = COGL_PIXEL_FORMAT_RGBA_8888;
required_format |= (format & COGL_PREMULT_BIT);
break;
/* The following three types of channel ordering
* are always defined using system word byte
* ordering (even according to GLES spec) */
case COGL_PIXEL_FORMAT_RGB_565:
glintformat = GL_RGB;
glformat = GL_RGB;
gltype = GL_UNSIGNED_SHORT_5_6_5;
break;
case COGL_PIXEL_FORMAT_RGBA_4444:
case COGL_PIXEL_FORMAT_RGBA_4444_PRE:
glintformat = GL_RGBA;
glformat = GL_RGBA;
gltype = GL_UNSIGNED_SHORT_4_4_4_4;
break;
case COGL_PIXEL_FORMAT_RGBA_5551:
case COGL_PIXEL_FORMAT_RGBA_5551_PRE:
glintformat = GL_RGBA;
glformat = GL_RGBA;
gltype = GL_UNSIGNED_SHORT_5_5_5_1;
break;
case COGL_PIXEL_FORMAT_ANY:
case COGL_PIXEL_FORMAT_YUV:
g_assert_not_reached ();
break;
}
/* All of the pixel formats are handled above so if this hits then
we've been given an invalid pixel format */
g_assert (glformat != 0);
if (out_glintformat != NULL)
*out_glintformat = glintformat;
if (out_glformat != NULL)
*out_glformat = glformat;
if (out_gltype != NULL)
*out_gltype = gltype;
return required_format;
}
static CoglBool
_cogl_driver_update_features (CoglContext *context,
GError **error)
{
CoglPrivateFeatureFlags private_flags = 0;
CoglFeatureFlags flags = 0;
const char *gl_extensions;
int num_stencil_bits = 0;
/* We have to special case getting the pointer to the glGetString
function because we need to use it to determine what functions we
can expect */
context->glGetString =
(void *) _cogl_renderer_get_proc_address (context->display->renderer,
"glGetString",
TRUE);
COGL_NOTE (WINSYS,
"Checking features\n"
" GL_VENDOR: %s\n"
" GL_RENDERER: %s\n"
" GL_VERSION: %s\n"
" GL_EXTENSIONS: %s",
context->glGetString (GL_VENDOR),
context->glGetString (GL_RENDERER),
context->glGetString (GL_VERSION),
context->glGetString (GL_EXTENSIONS));
_cogl_gpu_info_init (context, &context->gpu);
gl_extensions = (const char*) context->glGetString (GL_EXTENSIONS);
_cogl_feature_check_ext_functions (context,
-1 /* GL major version */,
-1 /* GL minor version */,
gl_extensions);
GE( context, glGetIntegerv (GL_STENCIL_BITS, &num_stencil_bits) );
/* We need at least three stencil bits to combine clips */
if (num_stencil_bits > 2)
private_flags |= COGL_PRIVATE_FEATURE_STENCIL_BUFFER;
#ifdef HAVE_COGL_GLES
if (context->driver == COGL_DRIVER_GLES1)
{
int max_clip_planes;
GE( context, glGetIntegerv (GL_MAX_CLIP_PLANES, &max_clip_planes) );
if (max_clip_planes >= 4)
private_flags |= COGL_PRIVATE_FEATURE_FOUR_CLIP_PLANES;
}
#endif
if (context->driver == COGL_DRIVER_GLES2)
{
flags |= COGL_FEATURE_SHADERS_GLSL | COGL_FEATURE_OFFSCREEN;
/* Note GLES 2 core doesn't support mipmaps for npot textures or
* repeat modes other than CLAMP_TO_EDGE. */
flags |= COGL_FEATURE_TEXTURE_NPOT_BASIC;
flags |= COGL_FEATURE_DEPTH_RANGE;
COGL_FLAGS_SET (context->features, COGL_FEATURE_ID_GLSL, TRUE);
COGL_FLAGS_SET (context->features, COGL_FEATURE_ID_OFFSCREEN, TRUE);
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_TEXTURE_NPOT_BASIC, TRUE);
COGL_FLAGS_SET (context->features, COGL_FEATURE_ID_DEPTH_RANGE, TRUE);
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_MIRRORED_REPEAT, TRUE);
}
private_flags |= COGL_PRIVATE_FEATURE_VBOS;
/* Both GLES 1.1 and GLES 2.0 support point sprites in core */
flags |= COGL_FEATURE_POINT_SPRITE;
COGL_FLAGS_SET (context->features, COGL_FEATURE_ID_POINT_SPRITE, TRUE);
if (context->glGenRenderbuffers)
{
flags |= COGL_FEATURE_OFFSCREEN;
COGL_FLAGS_SET (context->features, COGL_FEATURE_ID_OFFSCREEN, TRUE);
}
if (context->glBlitFramebuffer)
private_flags |= COGL_PRIVATE_FEATURE_OFFSCREEN_BLIT;
if (_cogl_check_extension ("GL_OES_element_index_uint", gl_extensions))
{
flags |= COGL_FEATURE_UNSIGNED_INT_INDICES;
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_UNSIGNED_INT_INDICES, TRUE);
}
if (_cogl_check_extension ("GL_OES_texture_npot", gl_extensions))
{
flags |= (COGL_FEATURE_TEXTURE_NPOT |
COGL_FEATURE_TEXTURE_NPOT_BASIC |
COGL_FEATURE_TEXTURE_NPOT_MIPMAP |
COGL_FEATURE_TEXTURE_NPOT_REPEAT);
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_TEXTURE_NPOT, TRUE);
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_TEXTURE_NPOT_BASIC, TRUE);
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP, TRUE);
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT, TRUE);
}
else if (_cogl_check_extension ("GL_IMG_texture_npot", gl_extensions))
{
flags |= (COGL_FEATURE_TEXTURE_NPOT_BASIC |
COGL_FEATURE_TEXTURE_NPOT_MIPMAP);
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_TEXTURE_NPOT_BASIC, TRUE);
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP, TRUE);
}
if (context->glTexImage3D)
{
flags |= COGL_FEATURE_TEXTURE_3D;
COGL_FLAGS_SET (context->features, COGL_FEATURE_ID_TEXTURE_3D, TRUE);
}
if (context->glMapBuffer)
{
/* The GL_OES_mapbuffer extension doesn't support mapping for
read */
flags |= COGL_FEATURE_MAP_BUFFER_FOR_WRITE;
COGL_FLAGS_SET (context->features,
COGL_FEATURE_ID_MAP_BUFFER_FOR_WRITE, TRUE);
}
if (context->glEGLImageTargetTexture2D)
private_flags |= COGL_PRIVATE_FEATURE_TEXTURE_2D_FROM_EGL_IMAGE;
if (_cogl_check_extension ("GL_OES_packed_depth_stencil", gl_extensions))
private_flags |= COGL_PRIVATE_FEATURE_OES_PACKED_DEPTH_STENCIL;
if (_cogl_check_extension ("GL_EXT_texture_format_BGRA8888", gl_extensions))
private_flags |= COGL_PRIVATE_FEATURE_TEXTURE_FORMAT_BGRA8888;
if (_cogl_check_extension ("GL_EXT_unpack_subimage", gl_extensions))
private_flags |= COGL_PRIVATE_FEATURE_UNPACK_SUBIMAGE;
/* Cache features */
context->private_feature_flags |= private_flags;
context->feature_flags |= flags;
return TRUE;
}
const CoglDriverVtable
_cogl_driver_gles =
{
_cogl_driver_pixel_format_from_gl_internal,
_cogl_driver_pixel_format_to_gl,
_cogl_driver_update_features
};