mutter/clutter/cogl/gl/cogl.c
Robert Bragg 33994caa71 [cogl-material] Support string based blending and layer combine descriptions
Setting up layer combine functions and blend modes is very awkward to do
programatically.  This adds a parser for string based descriptions which are
more consise and readable.

E.g. a material layer combine function could now be given as:
  "RGBA = ADD (TEXTURE[A], PREVIOUS[RGB])"
or
  "RGB = REPLACE (PREVIOUS)"
  "A = MODULATE (PREVIOUS, TEXTURE)"

The simple syntax and grammar are only designed to expose standard fixed
function hardware, more advanced combining must be done with shaders.

This includes standalone documentation of blend strings covering the aspects
that are common to blending and texture combining, and adds documentation
with examples specific to the new cogl_material_set_blend() and
cogl_material_layer_set_combine() functions.

Note: The hope is to remove the now redundant bits of the material API
before 1.0
2009-05-28 02:43:28 +01:00

504 lines
15 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 <gmodule.h>
#include "cogl.h"
#ifdef HAVE_CLUTTER_GLX
#include <dlfcn.h>
#include <GL/glx.h>
typedef CoglFuncPtr (*GLXGetProcAddressProc) (const guint8 *procName);
#endif
#include "cogl-internal.h"
#include "cogl-context.h"
CoglFuncPtr
cogl_get_proc_address (const gchar* name)
{
/* Sucks to ifdef here but not other option..? would be nice to
* split the code up for more reuse (once more backends use this
*/
#if defined(HAVE_CLUTTER_GLX)
static GLXGetProcAddressProc get_proc_func = NULL;
static void *dlhand = NULL;
if (get_proc_func == NULL && dlhand == NULL)
{
dlhand = dlopen (NULL, RTLD_LAZY);
if (dlhand)
{
dlerror ();
get_proc_func =
(GLXGetProcAddressProc) dlsym (dlhand, "glXGetProcAddress");
if (dlerror () != NULL)
{
get_proc_func =
(GLXGetProcAddressProc) dlsym (dlhand, "glXGetProcAddressARB");
}
if (dlerror () != NULL)
{
get_proc_func = NULL;
g_warning ("failed to bind GLXGetProcAddress "
"or GLXGetProcAddressARB");
}
}
}
if (get_proc_func)
return get_proc_func ((unsigned char*) name);
#elif defined(HAVE_CLUTTER_WIN32)
return (CoglFuncPtr) wglGetProcAddress ((LPCSTR) name);
#else /* HAVE_CLUTTER_WIN32 */
/* this should find the right function if the program is linked against a
* library providing it */
static GModule *module = NULL;
if (module == NULL)
module = g_module_open (NULL, G_MODULE_BIND_LAZY | G_MODULE_BIND_LOCAL);
if (module)
{
gpointer symbol;
if (g_module_symbol (module, name, &symbol))
return symbol;
}
#endif /* HAVE_CLUTTER_WIN32 */
return NULL;
}
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;
}
#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;
_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->pf_glCreateProgramObjectARB =
(COGL_PFNGLCREATEPROGRAMOBJECTARBPROC)
cogl_get_proc_address ("glCreateProgramObjectARB");
ctx->pf_glCreateShaderObjectARB =
(COGL_PFNGLCREATESHADEROBJECTARBPROC)
cogl_get_proc_address ("glCreateShaderObjectARB");
ctx->pf_glShaderSourceARB =
(COGL_PFNGLSHADERSOURCEARBPROC)
cogl_get_proc_address ("glShaderSourceARB");
ctx->pf_glCompileShaderARB =
(COGL_PFNGLCOMPILESHADERARBPROC)
cogl_get_proc_address ("glCompileShaderARB");
ctx->pf_glAttachObjectARB =
(COGL_PFNGLATTACHOBJECTARBPROC)
cogl_get_proc_address ("glAttachObjectARB");
ctx->pf_glLinkProgramARB =
(COGL_PFNGLLINKPROGRAMARBPROC)
cogl_get_proc_address ("glLinkProgramARB");
ctx->pf_glUseProgramObjectARB =
(COGL_PFNGLUSEPROGRAMOBJECTARBPROC)
cogl_get_proc_address ("glUseProgramObjectARB");
ctx->pf_glGetUniformLocationARB =
(COGL_PFNGLGETUNIFORMLOCATIONARBPROC)
cogl_get_proc_address ("glGetUniformLocationARB");
ctx->pf_glDeleteObjectARB =
(COGL_PFNGLDELETEOBJECTARBPROC)
cogl_get_proc_address ("glDeleteObjectARB");
ctx->pf_glGetInfoLogARB =
(COGL_PFNGLGETINFOLOGARBPROC)
cogl_get_proc_address ("glGetInfoLogARB");
ctx->pf_glGetObjectParameterivARB =
(COGL_PFNGLGETOBJECTPARAMETERIVARBPROC)
cogl_get_proc_address ("glGetObjectParameterivARB");
ctx->pf_glUniform1fARB =
(COGL_PFNGLUNIFORM1FARBPROC)
cogl_get_proc_address ("glUniform1fARB");
ctx->pf_glVertexAttribPointerARB =
(COGL_PFNGLVERTEXATTRIBPOINTERARBPROC)
cogl_get_proc_address ("glVertexAttribPointerARB");
ctx->pf_glEnableVertexAttribArrayARB =
(COGL_PFNGLENABLEVERTEXATTRIBARRAYARBPROC)
cogl_get_proc_address ("glEnableVertexAttribArrayARB");
ctx->pf_glDisableVertexAttribArrayARB =
(COGL_PFNGLDISABLEVERTEXATTRIBARRAYARBPROC)
cogl_get_proc_address ("glDisableVertexAttribArrayARB");
ctx->pf_glUniform2fARB =
(COGL_PFNGLUNIFORM2FARBPROC)
cogl_get_proc_address ("glUniform2fARB");
ctx->pf_glUniform3fARB =
(COGL_PFNGLUNIFORM3FARBPROC)
cogl_get_proc_address ("glUniform3fARB");
ctx->pf_glUniform4fARB =
(COGL_PFNGLUNIFORM4FARBPROC)
cogl_get_proc_address ("glUniform4fARB");
ctx->pf_glUniform1fvARB =
(COGL_PFNGLUNIFORM1FVARBPROC)
cogl_get_proc_address ("glUniform1fvARB");
ctx->pf_glUniform2fvARB =
(COGL_PFNGLUNIFORM2FVARBPROC)
cogl_get_proc_address ("glUniform2fvARB");
ctx->pf_glUniform3fvARB =
(COGL_PFNGLUNIFORM3FVARBPROC)
cogl_get_proc_address ("glUniform3fvARB");
ctx->pf_glUniform4fvARB =
(COGL_PFNGLUNIFORM4FVARBPROC)
cogl_get_proc_address ("glUniform4fvARB");
ctx->pf_glUniform1iARB =
(COGL_PFNGLUNIFORM1IARBPROC)
cogl_get_proc_address ("glUniform1iARB");
ctx->pf_glUniform2iARB =
(COGL_PFNGLUNIFORM2IARBPROC)
cogl_get_proc_address ("glUniform2iARB");
ctx->pf_glUniform3iARB =
(COGL_PFNGLUNIFORM3IARBPROC)
cogl_get_proc_address ("glUniform3iARB");
ctx->pf_glUniform4iARB =
(COGL_PFNGLUNIFORM4IARBPROC)
cogl_get_proc_address ("glUniform4iARB");
ctx->pf_glUniform1ivARB =
(COGL_PFNGLUNIFORM1IVARBPROC)
cogl_get_proc_address ("glUniform1ivARB");
ctx->pf_glUniform2ivARB =
(COGL_PFNGLUNIFORM2IVARBPROC)
cogl_get_proc_address ("glUniform2ivARB");
ctx->pf_glUniform3ivARB =
(COGL_PFNGLUNIFORM3IVARBPROC)
cogl_get_proc_address ("glUniform3ivARB");
ctx->pf_glUniform4ivARB =
(COGL_PFNGLUNIFORM4IVARBPROC)
cogl_get_proc_address ("glUniform4ivARB");
ctx->pf_glUniformMatrix2fvARB =
(COGL_PFNGLUNIFORMMATRIX2FVARBPROC)
cogl_get_proc_address ("glUniformMatrix2fvARB");
ctx->pf_glUniformMatrix3fvARB =
(COGL_PFNGLUNIFORMMATRIX3FVARBPROC)
cogl_get_proc_address ("glUniformMatrix3fvARB");
ctx->pf_glUniformMatrix4fvARB =
(COGL_PFNGLUNIFORMMATRIX4FVARBPROC)
cogl_get_proc_address ("glUniformMatrix4fvARB");
if (ctx->pf_glCreateProgramObjectARB &&
ctx->pf_glCreateShaderObjectARB &&
ctx->pf_glShaderSourceARB &&
ctx->pf_glCompileShaderARB &&
ctx->pf_glAttachObjectARB &&
ctx->pf_glLinkProgramARB &&
ctx->pf_glUseProgramObjectARB &&
ctx->pf_glGetUniformLocationARB &&
ctx->pf_glDeleteObjectARB &&
ctx->pf_glGetInfoLogARB &&
ctx->pf_glGetObjectParameterivARB &&
ctx->pf_glUniform1fARB &&
ctx->pf_glUniform2fARB &&
ctx->pf_glUniform3fARB &&
ctx->pf_glUniform4fARB &&
ctx->pf_glUniform1fvARB &&
ctx->pf_glUniform2fvARB &&
ctx->pf_glUniform3fvARB &&
ctx->pf_glUniform4fvARB &&
ctx->pf_glUniform1iARB &&
ctx->pf_glUniform2iARB &&
ctx->pf_glUniform3iARB &&
ctx->pf_glUniform4iARB &&
ctx->pf_glUniform1ivARB &&
ctx->pf_glUniform2ivARB &&
ctx->pf_glUniform3ivARB &&
ctx->pf_glUniform4ivARB &&
ctx->pf_glUniformMatrix2fvARB &&
ctx->pf_glUniformMatrix3fvARB &&
ctx->pf_glUniformMatrix4fvARB &&
ctx->pf_glVertexAttribPointerARB &&
ctx->pf_glEnableVertexAttribArrayARB &&
ctx->pf_glDisableVertexAttribArrayARB)
flags |= COGL_FEATURE_SHADERS_GLSL;
}
if (cogl_check_extension ("GL_EXT_framebuffer_object", gl_extensions) ||
cogl_check_extension ("GL_ARB_framebuffer_object", gl_extensions))
{
ctx->pf_glGenRenderbuffersEXT =
(COGL_PFNGLGENRENDERBUFFERSEXTPROC)
cogl_get_proc_address ("glGenRenderbuffersEXT");
ctx->pf_glDeleteRenderbuffersEXT =
(COGL_PFNGLDELETERENDERBUFFERSEXTPROC)
cogl_get_proc_address ("glDeleteRenderbuffersEXT");
ctx->pf_glBindRenderbufferEXT =
(COGL_PFNGLBINDRENDERBUFFEREXTPROC)
cogl_get_proc_address ("glBindRenderbufferEXT");
ctx->pf_glRenderbufferStorageEXT =
(COGL_PFNGLRENDERBUFFERSTORAGEEXTPROC)
cogl_get_proc_address ("glRenderbufferStorageEXT");
ctx->pf_glGenFramebuffersEXT =
(COGL_PFNGLGENFRAMEBUFFERSEXTPROC)
cogl_get_proc_address ("glGenFramebuffersEXT");
ctx->pf_glBindFramebufferEXT =
(COGL_PFNGLBINDFRAMEBUFFEREXTPROC)
cogl_get_proc_address ("glBindFramebufferEXT");
ctx->pf_glFramebufferTexture2DEXT =
(COGL_PFNGLFRAMEBUFFERTEXTURE2DEXTPROC)
cogl_get_proc_address ("glFramebufferTexture2DEXT");
ctx->pf_glFramebufferRenderbufferEXT =
(COGL_PFNGLFRAMEBUFFERRENDERBUFFEREXTPROC)
cogl_get_proc_address ("glFramebufferRenderbufferEXT");
ctx->pf_glCheckFramebufferStatusEXT =
(COGL_PFNGLCHECKFRAMEBUFFERSTATUSEXTPROC)
cogl_get_proc_address ("glCheckFramebufferStatusEXT");
ctx->pf_glDeleteFramebuffersEXT =
(COGL_PFNGLDELETEFRAMEBUFFERSEXTPROC)
cogl_get_proc_address ("glDeleteFramebuffersEXT");
if (ctx->pf_glGenRenderbuffersEXT &&
ctx->pf_glBindRenderbufferEXT &&
ctx->pf_glRenderbufferStorageEXT &&
ctx->pf_glGenFramebuffersEXT &&
ctx->pf_glBindFramebufferEXT &&
ctx->pf_glFramebufferTexture2DEXT &&
ctx->pf_glFramebufferRenderbufferEXT &&
ctx->pf_glCheckFramebufferStatusEXT &&
ctx->pf_glDeleteFramebuffersEXT)
flags |= COGL_FEATURE_OFFSCREEN;
}
if (cogl_check_extension ("GL_EXT_framebuffer_blit", gl_extensions))
{
ctx->pf_glBlitFramebufferEXT =
(COGL_PFNGLBLITFRAMEBUFFEREXTPROC)
cogl_get_proc_address ("glBlitFramebufferEXT");
if (ctx->pf_glBlitFramebufferEXT)
flags |= COGL_FEATURE_OFFSCREEN_BLIT;
}
if (cogl_check_extension ("GL_EXT_framebuffer_multisample", gl_extensions))
{
ctx->pf_glRenderbufferStorageMultisampleEXT =
(COGL_PFNGLRENDERBUFFERSTORAGEMULTISAMPLEEXTPROC)
cogl_get_proc_address ("glRenderbufferStorageMultisampleEXT");
if (ctx->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->pf_glGenBuffersARB =
(COGL_PFNGLGENBUFFERSARBPROC)
cogl_get_proc_address ("glGenBuffersARB");
ctx->pf_glBindBufferARB =
(COGL_PFNGLBINDBUFFERARBPROC)
cogl_get_proc_address ("glBindBufferARB");
ctx->pf_glBufferDataARB =
(COGL_PFNGLBUFFERDATAARBPROC)
cogl_get_proc_address ("glBufferDataARB");
ctx->pf_glBufferSubDataARB =
(COGL_PFNGLBUFFERSUBDATAARBPROC)
cogl_get_proc_address ("glBufferSubDataARB");
ctx->pf_glDeleteBuffersARB =
(COGL_PFNGLDELETEBUFFERSARBPROC)
cogl_get_proc_address ("glDeleteBuffersARB");
ctx->pf_glMapBufferARB =
(COGL_PFNGLMAPBUFFERARBPROC)
cogl_get_proc_address ("glMapBufferARB");
ctx->pf_glUnmapBufferARB =
(COGL_PFNGLUNMAPBUFFERARBPROC)
cogl_get_proc_address ("glUnmapBufferARB");
if (ctx->pf_glGenBuffersARB
&& ctx->pf_glBindBufferARB
&& ctx->pf_glBufferDataARB
&& ctx->pf_glBufferSubDataARB
&& ctx->pf_glDeleteBuffersARB
&& ctx->pf_glMapBufferARB
&& ctx->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->pf_glDrawRangeElements =
(COGL_PFNGLDRAWRANGEELEMENTSPROC)
cogl_get_proc_address ("glDrawRangeElements");
ctx->pf_glActiveTexture =
(COGL_PFNGLACTIVETEXTUREPROC)
cogl_get_proc_address ("glActiveTexture");
ctx->pf_glClientActiveTexture =
(COGL_PFNGLCLIENTACTIVETEXTUREPROC)
cogl_get_proc_address ("glClientActiveTexture");
/* Available in 1.4 */
ctx->pf_glBlendFuncSeparate =
(COGL_PFNGLBLENDFUNCSEPARATEPROC)
cogl_get_proc_address ("glBlendFuncSeparate");
/* Available in 2.0 */
ctx->pf_glBlendEquationSeparate =
(COGL_PFNGLBLENDEQUATIONSEPARATEPROC)
cogl_get_proc_address ("glBlendEquationSeparate");
/* Cache features */
ctx->feature_flags = flags;
ctx->features_cached = TRUE;
}