mutter/cogl/driver/gl/cogl-shader.c
Neil Roberts 058d79dce2 cogl: Make it easier to add checks for GL extensions
Previously if you need to depend on a new GL feature you had to:

- Add typedefs for all of the functions in cogl-defines.h.in

- Add function pointers for each of the functions in
  cogl-context-driver.h

- Add an initializer for the function pointers in
  cogl-context-driver.c

- Add a check for the extension and all of the functions in
  cogl_features_init. If the extension is available under multiple
  names then you have to duplicate the checks.

This is quite tedious and error prone. This patch moves all of the
features and their functions into a list of macro invocations in
cogl-feature-functions.h. The macros can be redefined to implement all
of the above tasks from the same header.

The features are described in a struct with a pointer to a table of
functions. A new function takes the feature description from this
struct and checks for its availability. The feature can take a list of
extension names with a list of alternate namespaces (such as "EXT" or
"ARB"). It can also detect the feature from a particular version of
GL.

The typedefs are now gone and instead the function pointer in the Cogl
context just directly contains the type.

Some of the functions in the context were previously declared with the
'ARB' extension. This has been removed so that now all the functions
have no suffix. This makes more sense when the extension could
potentially be merged into GL core as well.
2009-11-17 15:11:26 +00:00

177 lines
4.3 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, 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 "cogl.h"
#include "cogl-shader-private.h"
#include "cogl-internal.h"
#include "cogl-context.h"
#include "cogl-handle.h"
#include <glib.h>
#define glCreateShaderObject ctx->drv.pf_glCreateShaderObject
#define glGetObjectParameteriv ctx->drv.pf_glGetObjectParameteriv
#define glGetInfoLog ctx->drv.pf_glGetInfoLog
#define glCompileShader ctx->drv.pf_glCompileShader
#define glShaderSource ctx->drv.pf_glShaderSource
#define glDeleteObject ctx->drv.pf_glDeleteObject
static void _cogl_shader_free (CoglShader *shader);
COGL_HANDLE_DEFINE (Shader, shader);
static void
_cogl_shader_free (CoglShader *shader)
{
/* Frees shader resources but its handle is not
released! Do that separately before this! */
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
glDeleteObject (shader->gl_handle);
}
CoglHandle
cogl_create_shader (CoglShaderType type)
{
CoglShader *shader;
GLenum gl_type;
_COGL_GET_CONTEXT (ctx, COGL_INVALID_HANDLE);
if (type == COGL_SHADER_TYPE_VERTEX)
gl_type = GL_VERTEX_SHADER;
else if (type == COGL_SHADER_TYPE_FRAGMENT)
gl_type = GL_FRAGMENT_SHADER;
else
{
g_warning ("Unexpected shader type (0x%08lX) given to "
"cogl_create_shader", (unsigned long) type);
return COGL_INVALID_HANDLE;
}
shader = g_slice_new (CoglShader);
shader->gl_handle = glCreateShaderObject (gl_type);
return _cogl_shader_handle_new (shader);
}
void
cogl_shader_source (CoglHandle handle,
const char *source)
{
CoglShader *shader;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (!cogl_is_shader (handle))
return;
shader = _cogl_shader_pointer_from_handle (handle);
glShaderSource (shader->gl_handle, 1, &source, NULL);
}
void
cogl_shader_compile (CoglHandle handle)
{
CoglShader *shader;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (!cogl_is_shader (handle))
return;
shader = _cogl_shader_pointer_from_handle (handle);
glCompileShader (shader->gl_handle);
}
gchar *
cogl_shader_get_info_log (CoglHandle handle)
{
CoglShader *shader;
char buffer[512];
int len;
_COGL_GET_CONTEXT (ctx, NULL);
if (!cogl_is_shader (handle))
return NULL;
shader = _cogl_shader_pointer_from_handle (handle);
glGetInfoLog (shader->gl_handle, 511, &len, buffer);
buffer[len]='\0';
return g_strdup (buffer);
}
CoglShaderType
cogl_shader_get_type (CoglHandle handle)
{
GLint type;
CoglShader *shader;
_COGL_GET_CONTEXT (ctx, COGL_SHADER_TYPE_VERTEX);
if (!cogl_is_shader (handle))
{
g_warning ("Non shader handle type passed to cogl_shader_get_type");
return COGL_SHADER_TYPE_VERTEX;
}
shader = _cogl_shader_pointer_from_handle (handle);
GE (glGetObjectParameteriv (shader->gl_handle, GL_SHADER_TYPE, &type));
if (type == GL_VERTEX_SHADER)
return COGL_SHADER_TYPE_VERTEX;
else if (type == GL_FRAGMENT_SHADER)
return COGL_SHADER_TYPE_VERTEX;
else
{
g_warning ("Unexpected shader type 0x%08lX", (unsigned long)type);
return COGL_SHADER_TYPE_VERTEX;
}
}
gboolean
cogl_shader_is_compiled (CoglHandle handle)
{
GLint status;
CoglShader *shader;
_COGL_GET_CONTEXT (ctx, FALSE);
if (!cogl_is_shader (handle))
return FALSE;
shader = _cogl_shader_pointer_from_handle (handle);
GE (glGetObjectParameteriv (shader->gl_handle, GL_COMPILE_STATUS, &status));
if (status == GL_TRUE)
return TRUE;
else
return FALSE;
}