mutter/cogl/driver/gl/cogl.c
Robert Bragg bb3a008318 [draw-buffers] First pass at overhauling Cogl's framebuffer management
Cogl's support for offscreen rendering was originally written just to support
the clutter_texture_new_from_actor API and due to lack of documentation and
several confusing - non orthogonal - side effects of using the API it wasn't
really possible to use directly.

This commit does a number of things:
- It removes {gl,gles}/cogl-fbo.{c,h} and adds shared cogl-draw-buffer.{c,h}
  files instead which should be easier to maintain.
- internally CoglFbo objects are now called CoglDrawBuffers. A
  CoglDrawBuffer is an abstract base class that is inherited from to
  implement CoglOnscreen and CoglOffscreen draw buffers.  CoglOffscreen draw
  buffers will initially be used to support the
  cogl_offscreen_new_to_texture API, and CoglOnscreen draw buffers will
  start to be used internally to represent windows as we aim to migrate some
  of Clutter's backend code to Cogl.
- It makes draw buffer objects the owners of the following state:
  - viewport
  - projection matrix stack
  - modelview matrix stack
  - clip state
(This means when you switch between draw buffers you will automatically be
 switching to their associated viewport, matrix and clip state)

Aside from hopefully making cogl_offscreen_new_to_texture be more useful
short term by having simpler and well defined semantics for
cogl_set_draw_buffer, as mentioned above this is the first step for a couple
of other things:
- Its a step toward moving ownership for windows down from Clutter backends
  into Cogl, by (internally at least) introducing the CoglOnscreen draw
  buffer.  Note: the plan is that cogl_set_draw_buffer will accept on or
  offscreen draw buffer handles, and the "target" argument will become
  redundant since we will instead query the type of the given draw buffer
  handle.
- Because we have a common type for on and offscreen framebuffers we can
  provide a unified API for framebuffer management. Things like:
  - blitting between buffers
  - managing ancillary buffers (e.g. attaching depth and stencil buffers)
  - size requisition
  - clearing
2009-11-03 17:23:03 +00:00

444 lines
14 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, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "cogl.h"
#include "cogl-internal.h"
#include "cogl-context.h"
typedef struct _CoglGLSymbolTableEntry
{
const char *name;
void *ptr;
} CoglGLSymbolTableEntry;
gboolean
cogl_check_extension (const gchar *name, const gchar *ext)
{
gchar *end;
gint name_len, n;
if (name == NULL || ext == NULL)
return FALSE;
end = (gchar*)(ext + strlen(ext));
name_len = strlen(name);
while (ext < end)
{
n = strcspn(ext, " ");
if ((name_len == n) && (!strncmp(name, ext, n)))
return TRUE;
ext += (n + 1);
}
return FALSE;
}
gboolean
_cogl_resolve_gl_symbols (CoglGLSymbolTableEntry *symbol_table,
const char *suffix)
{
int i;
gboolean status = TRUE;
for (i = 0; symbol_table[i].name; i++)
{
char *full_name = g_strdup_printf ("%s%s", symbol_table[i].name, suffix);
*((CoglFuncPtr *)symbol_table[i].ptr) = cogl_get_proc_address (full_name);
g_free (full_name);
if (!*((CoglFuncPtr *)symbol_table[i].ptr))
{
status = FALSE;
break;
}
}
return status;
}
#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
void
_cogl_features_init (void)
{
CoglFeatureFlags flags = 0;
const gchar *gl_extensions;
GLint max_clip_planes = 0;
GLint num_stencil_bits = 0;
gboolean fbo_ARB = FALSE;
gboolean fbo_EXT = FALSE;
const char *suffix;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
flags = COGL_FEATURE_TEXTURE_READ_PIXELS;
gl_extensions = (const gchar*) glGetString (GL_EXTENSIONS);
if (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;
}
#ifdef GL_YCBCR_MESA
if (cogl_check_extension ("GL_MESA_ycbcr_texture", gl_extensions))
{
flags |= COGL_FEATURE_TEXTURE_YUV;
}
#endif
if (cogl_check_extension ("GL_ARB_shader_objects", gl_extensions) &&
cogl_check_extension ("GL_ARB_vertex_shader", gl_extensions) &&
cogl_check_extension ("GL_ARB_fragment_shader", gl_extensions))
{
ctx->drv.pf_glCreateProgramObjectARB =
(COGL_PFNGLCREATEPROGRAMOBJECTARBPROC)
cogl_get_proc_address ("glCreateProgramObjectARB");
ctx->drv.pf_glCreateShaderObjectARB =
(COGL_PFNGLCREATESHADEROBJECTARBPROC)
cogl_get_proc_address ("glCreateShaderObjectARB");
ctx->drv.pf_glShaderSourceARB =
(COGL_PFNGLSHADERSOURCEARBPROC)
cogl_get_proc_address ("glShaderSourceARB");
ctx->drv.pf_glCompileShaderARB =
(COGL_PFNGLCOMPILESHADERARBPROC)
cogl_get_proc_address ("glCompileShaderARB");
ctx->drv.pf_glAttachObjectARB =
(COGL_PFNGLATTACHOBJECTARBPROC)
cogl_get_proc_address ("glAttachObjectARB");
ctx->drv.pf_glLinkProgramARB =
(COGL_PFNGLLINKPROGRAMARBPROC)
cogl_get_proc_address ("glLinkProgramARB");
ctx->drv.pf_glUseProgramObjectARB =
(COGL_PFNGLUSEPROGRAMOBJECTARBPROC)
cogl_get_proc_address ("glUseProgramObjectARB");
ctx->drv.pf_glGetUniformLocationARB =
(COGL_PFNGLGETUNIFORMLOCATIONARBPROC)
cogl_get_proc_address ("glGetUniformLocationARB");
ctx->drv.pf_glDeleteObjectARB =
(COGL_PFNGLDELETEOBJECTARBPROC)
cogl_get_proc_address ("glDeleteObjectARB");
ctx->drv.pf_glGetInfoLogARB =
(COGL_PFNGLGETINFOLOGARBPROC)
cogl_get_proc_address ("glGetInfoLogARB");
ctx->drv.pf_glGetObjectParameterivARB =
(COGL_PFNGLGETOBJECTPARAMETERIVARBPROC)
cogl_get_proc_address ("glGetObjectParameterivARB");
ctx->drv.pf_glUniform1fARB =
(COGL_PFNGLUNIFORM1FARBPROC)
cogl_get_proc_address ("glUniform1fARB");
ctx->drv.pf_glVertexAttribPointerARB =
(COGL_PFNGLVERTEXATTRIBPOINTERARBPROC)
cogl_get_proc_address ("glVertexAttribPointerARB");
ctx->drv.pf_glEnableVertexAttribArrayARB =
(COGL_PFNGLENABLEVERTEXATTRIBARRAYARBPROC)
cogl_get_proc_address ("glEnableVertexAttribArrayARB");
ctx->drv.pf_glDisableVertexAttribArrayARB =
(COGL_PFNGLDISABLEVERTEXATTRIBARRAYARBPROC)
cogl_get_proc_address ("glDisableVertexAttribArrayARB");
ctx->drv.pf_glUniform2fARB =
(COGL_PFNGLUNIFORM2FARBPROC)
cogl_get_proc_address ("glUniform2fARB");
ctx->drv.pf_glUniform3fARB =
(COGL_PFNGLUNIFORM3FARBPROC)
cogl_get_proc_address ("glUniform3fARB");
ctx->drv.pf_glUniform4fARB =
(COGL_PFNGLUNIFORM4FARBPROC)
cogl_get_proc_address ("glUniform4fARB");
ctx->drv.pf_glUniform1fvARB =
(COGL_PFNGLUNIFORM1FVARBPROC)
cogl_get_proc_address ("glUniform1fvARB");
ctx->drv.pf_glUniform2fvARB =
(COGL_PFNGLUNIFORM2FVARBPROC)
cogl_get_proc_address ("glUniform2fvARB");
ctx->drv.pf_glUniform3fvARB =
(COGL_PFNGLUNIFORM3FVARBPROC)
cogl_get_proc_address ("glUniform3fvARB");
ctx->drv.pf_glUniform4fvARB =
(COGL_PFNGLUNIFORM4FVARBPROC)
cogl_get_proc_address ("glUniform4fvARB");
ctx->drv.pf_glUniform1iARB =
(COGL_PFNGLUNIFORM1IARBPROC)
cogl_get_proc_address ("glUniform1iARB");
ctx->drv.pf_glUniform2iARB =
(COGL_PFNGLUNIFORM2IARBPROC)
cogl_get_proc_address ("glUniform2iARB");
ctx->drv.pf_glUniform3iARB =
(COGL_PFNGLUNIFORM3IARBPROC)
cogl_get_proc_address ("glUniform3iARB");
ctx->drv.pf_glUniform4iARB =
(COGL_PFNGLUNIFORM4IARBPROC)
cogl_get_proc_address ("glUniform4iARB");
ctx->drv.pf_glUniform1ivARB =
(COGL_PFNGLUNIFORM1IVARBPROC)
cogl_get_proc_address ("glUniform1ivARB");
ctx->drv.pf_glUniform2ivARB =
(COGL_PFNGLUNIFORM2IVARBPROC)
cogl_get_proc_address ("glUniform2ivARB");
ctx->drv.pf_glUniform3ivARB =
(COGL_PFNGLUNIFORM3IVARBPROC)
cogl_get_proc_address ("glUniform3ivARB");
ctx->drv.pf_glUniform4ivARB =
(COGL_PFNGLUNIFORM4IVARBPROC)
cogl_get_proc_address ("glUniform4ivARB");
ctx->drv.pf_glUniformMatrix2fvARB =
(COGL_PFNGLUNIFORMMATRIX2FVARBPROC)
cogl_get_proc_address ("glUniformMatrix2fvARB");
ctx->drv.pf_glUniformMatrix3fvARB =
(COGL_PFNGLUNIFORMMATRIX3FVARBPROC)
cogl_get_proc_address ("glUniformMatrix3fvARB");
ctx->drv.pf_glUniformMatrix4fvARB =
(COGL_PFNGLUNIFORMMATRIX4FVARBPROC)
cogl_get_proc_address ("glUniformMatrix4fvARB");
if (ctx->drv.pf_glCreateProgramObjectARB &&
ctx->drv.pf_glCreateShaderObjectARB &&
ctx->drv.pf_glShaderSourceARB &&
ctx->drv.pf_glCompileShaderARB &&
ctx->drv.pf_glAttachObjectARB &&
ctx->drv.pf_glLinkProgramARB &&
ctx->drv.pf_glUseProgramObjectARB &&
ctx->drv.pf_glGetUniformLocationARB &&
ctx->drv.pf_glDeleteObjectARB &&
ctx->drv.pf_glGetInfoLogARB &&
ctx->drv.pf_glGetObjectParameterivARB &&
ctx->drv.pf_glUniform1fARB &&
ctx->drv.pf_glUniform2fARB &&
ctx->drv.pf_glUniform3fARB &&
ctx->drv.pf_glUniform4fARB &&
ctx->drv.pf_glUniform1fvARB &&
ctx->drv.pf_glUniform2fvARB &&
ctx->drv.pf_glUniform3fvARB &&
ctx->drv.pf_glUniform4fvARB &&
ctx->drv.pf_glUniform1iARB &&
ctx->drv.pf_glUniform2iARB &&
ctx->drv.pf_glUniform3iARB &&
ctx->drv.pf_glUniform4iARB &&
ctx->drv.pf_glUniform1ivARB &&
ctx->drv.pf_glUniform2ivARB &&
ctx->drv.pf_glUniform3ivARB &&
ctx->drv.pf_glUniform4ivARB &&
ctx->drv.pf_glUniformMatrix2fvARB &&
ctx->drv.pf_glUniformMatrix3fvARB &&
ctx->drv.pf_glUniformMatrix4fvARB &&
ctx->drv.pf_glVertexAttribPointerARB &&
ctx->drv.pf_glEnableVertexAttribArrayARB &&
ctx->drv.pf_glDisableVertexAttribArrayARB)
flags |= COGL_FEATURE_SHADERS_GLSL;
}
fbo_ARB = cogl_check_extension ("GL_ARB_framebuffer_object", gl_extensions);
if (fbo_ARB)
suffix = "";
else
{
fbo_EXT = cogl_check_extension ("GL_EXT_framebuffer_object", gl_extensions);
if (fbo_EXT)
suffix = "EXT";
}
if (fbo_ARB || fbo_EXT)
{
CoglGLSymbolTableEntry symbol_table[] = {
{"glGenRenderbuffers", &ctx->drv.pf_glGenRenderbuffers},
{"glDeleteRenderbuffers", &ctx->drv.pf_glDeleteRenderbuffers},
{"glBindRenderbuffer", &ctx->drv.pf_glBindRenderbuffer},
{"glRenderbufferStorage", &ctx->drv.pf_glRenderbufferStorage},
{"glGenFramebuffers", &ctx->drv.pf_glGenFramebuffers},
{"glBindFramebuffer", &ctx->drv.pf_glBindFramebuffer},
{"glFramebufferTexture2D", &ctx->drv.pf_glFramebufferTexture2D},
{"glFramebufferRenderbuffer", &ctx->drv.pf_glFramebufferRenderbuffer},
{"glCheckFramebufferStatus", &ctx->drv.pf_glCheckFramebufferStatus},
{"glDeleteFramebuffers", &ctx->drv.pf_glDeleteFramebuffers},
{"glGenerateMipmap", &ctx->drv.pf_glGenerateMipmap},
{NULL, NULL}
};
if (_cogl_resolve_gl_symbols (symbol_table, suffix))
flags |= COGL_FEATURE_OFFSCREEN;
}
if (cogl_check_extension ("GL_EXT_framebuffer_blit", gl_extensions))
{
ctx->drv.pf_glBlitFramebufferEXT =
(COGL_PFNGLBLITFRAMEBUFFEREXTPROC)
cogl_get_proc_address ("glBlitFramebufferEXT");
if (ctx->drv.pf_glBlitFramebufferEXT)
flags |= COGL_FEATURE_OFFSCREEN_BLIT;
}
if (cogl_check_extension ("GL_EXT_framebuffer_multisample", gl_extensions))
{
ctx->drv.pf_glRenderbufferStorageMultisampleEXT =
(COGL_PFNGLRENDERBUFFERSTORAGEMULTISAMPLEEXTPROC)
cogl_get_proc_address ("glRenderbufferStorageMultisampleEXT");
if (ctx->drv.pf_glRenderbufferStorageMultisampleEXT)
flags |= COGL_FEATURE_OFFSCREEN_MULTISAMPLE;
}
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;
if (cogl_check_extension ("GL_ARB_vertex_buffer_object", gl_extensions))
{
ctx->drv.pf_glGenBuffersARB =
(COGL_PFNGLGENBUFFERSARBPROC)
cogl_get_proc_address ("glGenBuffersARB");
ctx->drv.pf_glBindBufferARB =
(COGL_PFNGLBINDBUFFERARBPROC)
cogl_get_proc_address ("glBindBufferARB");
ctx->drv.pf_glBufferDataARB =
(COGL_PFNGLBUFFERDATAARBPROC)
cogl_get_proc_address ("glBufferDataARB");
ctx->drv.pf_glBufferSubDataARB =
(COGL_PFNGLBUFFERSUBDATAARBPROC)
cogl_get_proc_address ("glBufferSubDataARB");
ctx->drv.pf_glDeleteBuffersARB =
(COGL_PFNGLDELETEBUFFERSARBPROC)
cogl_get_proc_address ("glDeleteBuffersARB");
ctx->drv.pf_glMapBufferARB =
(COGL_PFNGLMAPBUFFERARBPROC)
cogl_get_proc_address ("glMapBufferARB");
ctx->drv.pf_glUnmapBufferARB =
(COGL_PFNGLUNMAPBUFFERARBPROC)
cogl_get_proc_address ("glUnmapBufferARB");
if (ctx->drv.pf_glGenBuffersARB
&& ctx->drv.pf_glBindBufferARB
&& ctx->drv.pf_glBufferDataARB
&& ctx->drv.pf_glBufferSubDataARB
&& ctx->drv.pf_glDeleteBuffersARB
&& ctx->drv.pf_glMapBufferARB
&& ctx->drv.pf_glUnmapBufferARB)
flags |= COGL_FEATURE_VBOS;
}
/* These should always be available because they are defined in GL
1.2, but we can't call it directly because under Windows
functions > 1.1 aren't exported */
ctx->drv.pf_glDrawRangeElements =
(COGL_PFNGLDRAWRANGEELEMENTSPROC)
cogl_get_proc_address ("glDrawRangeElements");
ctx->drv.pf_glActiveTexture =
(COGL_PFNGLACTIVETEXTUREPROC)
cogl_get_proc_address ("glActiveTexture");
ctx->drv.pf_glClientActiveTexture =
(COGL_PFNGLCLIENTACTIVETEXTUREPROC)
cogl_get_proc_address ("glClientActiveTexture");
ctx->drv.pf_glBlendEquation =
(COGL_PFNGLBLENDEQUATIONPROC)
cogl_get_proc_address ("glBlendEquation");
ctx->drv.pf_glBlendColor =
(COGL_PFNGLBLENDCOLORPROC)
cogl_get_proc_address ("glBlendColor");
/* Available in 1.4 */
ctx->drv.pf_glBlendFuncSeparate =
(COGL_PFNGLBLENDFUNCSEPARATEPROC)
cogl_get_proc_address ("glBlendFuncSeparate");
/* Available in 2.0 */
ctx->drv.pf_glBlendEquationSeparate =
(COGL_PFNGLBLENDEQUATIONSEPARATEPROC)
cogl_get_proc_address ("glBlendEquationSeparate");
/* Cache features */
ctx->feature_flags = flags;
ctx->features_cached = TRUE;
}