mutter/cogl/driver/gl/cogl-shader.c
Robert Bragg acc44161c1 material: Adds backend abstraction for fragment processing
As part of an effort to improve the architecture of CoglMaterial
internally this overhauls how we flush layer state to OpenGL by adding a
formal backend abstraction for fragment processing and further
formalizing the CoglTextureUnit abstraction.

There are three backends: "glsl", "arbfp" and "fixed". The fixed backend
uses the OpenGL fixed function APIs to setup the fragment processing,
the arbfp backend uses code generation to handle fragment processing
using an ARBfp program, and the GLSL backend is currently only there as
a formality to handle user programs associated with a material. (i.e.
the glsl backend doesn't yet support code generation)

The GLSL backend has highest precedence, then arbfp and finally the
fixed. If a backend can't support some particular CoglMaterial feature
then it will fallback to the next backend.

This adds three new COGL_DEBUG options:
* "disable-texturing" as expected should disable all texturing
* "disable-arbfp" always make the arbfp backend fallback
* "disable-glsl" always make the glsl backend fallback
* "show-source" show code generated by the arbfp/glsl backends
2010-06-09 17:15:59 +01:00

177 lines
4.2 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2007,2008,2009,2010 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 "cogl.h"
#include "cogl-shader-private.h"
#include "cogl-internal.h"
#include "cogl-context.h"
#include "cogl-handle.h"
#include <glib.h>
#define glCreateShader ctx->drv.pf_glCreateShader
#define glGetShaderiv ctx->drv.pf_glGetShaderiv
#define glGetShaderInfoLog ctx->drv.pf_glGetShaderInfoLog
#define glCompileShader ctx->drv.pf_glCompileShader
#define glShaderSource ctx->drv.pf_glShaderSource
#define glDeleteShader ctx->drv.pf_glDeleteShader
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);
glDeleteShader (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 = glCreateShader (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);
}
char *
cogl_shader_get_info_log (CoglHandle handle)
{
CoglShader *shader;
char buffer[512];
GLsizei len;
_COGL_GET_CONTEXT (ctx, NULL);
if (!cogl_is_shader (handle))
return NULL;
shader = _cogl_shader_pointer_from_handle (handle);
glGetShaderInfoLog (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 (glGetShaderiv (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 (glGetShaderiv (shader->gl_handle, GL_COMPILE_STATUS, &status));
if (status == GL_TRUE)
return TRUE;
else
return FALSE;
}