mutter/cogl/cogl-primitive.c
Robert Bragg 9498d505dd cogl: Adds experimental CoglPrimitive API
A CoglPrimitive is a retainable object for drawing a single primitive,
such as a triangle strip, fan or list.

CoglPrimitives build on CoglVertexAttributes and CoglIndices which
themselves build on CoglVertexArrays and CoglIndexArrays respectively.

A CoglPrimitive encapsulates enough information such that it can be
retained in a queue (e.g. the Cogl Journal, or renderlists in the
future) and drawn at some later time.
2010-11-03 18:04:31 +00:00

224 lines
5.8 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 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/>.
*
*
*
* Authors:
* Robert Bragg <robert@linux.intel.com>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl-object-private.h"
#include "cogl-primitive.h"
#include "cogl-primitive-private.h"
#include <stdarg.h>
static void _cogl_primitive_free (CoglPrimitive *primitive);
COGL_OBJECT_DEFINE (Primitive, primitive);
/* XXX: should we have an n_attributes arg instead of NULL terminating? */
CoglPrimitive *
cogl_primitive_new_with_attributes_array (CoglVerticesMode mode,
int n_vertices,
CoglVertexAttribute **attributes)
{
CoglPrimitive *primitive = g_slice_new (CoglPrimitive);
int i;
primitive->mode = mode;
primitive->first_vertex = 0;
primitive->n_vertices = n_vertices;
primitive->indices = NULL;
primitive->attributes =
g_array_new (TRUE, FALSE, sizeof (CoglVertexAttribute *));
for (i = 0; attributes[i]; i++)
{
CoglVertexAttribute *attribute = attributes[i];
cogl_object_ref (attribute);
g_return_val_if_fail (cogl_is_vertex_attribute (attributes), NULL);
g_array_append_val (primitive->attributes, attribute);
}
return _cogl_primitive_object_new (primitive);
}
CoglPrimitive *
cogl_primitive_new (CoglVerticesMode mode,
int n_vertices,
...)
{
va_list ap;
int n_attributes;
CoglVertexAttribute **attributes;
int i;
CoglVertexAttribute *attribute;
va_start (ap, n_vertices);
for (n_attributes = 0; va_arg (ap, CoglVertexAttribute *); n_attributes++)
;
va_end (ap);
attributes = g_alloca (sizeof (CoglVertexAttribute *) * (n_attributes + 1));
attributes[n_attributes] = NULL;
va_start (ap, n_vertices);
for (i = 0; (attribute = va_arg (ap, CoglVertexAttribute *)); i++)
attributes[i] = attribute;
va_end (ap);
return cogl_primitive_new_with_attributes_array (mode, n_vertices,
attributes);
}
static void
free_attributes_list (CoglPrimitive *primitive)
{
int i;
for (i = 0; i < primitive->attributes->len; i++)
{
CoglVertexAttribute *attribute =
g_array_index (primitive->attributes, CoglVertexAttribute *, i);
cogl_object_unref (attribute);
}
g_array_set_size (primitive->attributes, 0);
}
static void
_cogl_primitive_free (CoglPrimitive *primitive)
{
free_attributes_list (primitive);
g_array_free (primitive->attributes, TRUE);
g_slice_free (CoglPrimitive, primitive);
}
void
cogl_primitive_set_attributes (CoglPrimitive *primitive,
CoglVertexAttribute **attributes)
{
int i;
free_attributes_list (primitive);
g_array_set_size (primitive->attributes, 0);
for (i = 0; attributes[i]; i++)
{
cogl_object_ref (attributes[i]);
g_return_if_fail (cogl_is_vertex_attribute (attributes[i]));
g_array_append_val (primitive->attributes, attributes[i]);
}
}
int
cogl_primitive_get_first_vertex (CoglPrimitive *primitive)
{
g_return_val_if_fail (cogl_is_primitive (primitive), 0);
return primitive->first_vertex;
}
void
cogl_primitive_set_first_vertex (CoglPrimitive *primitive,
int first_vertex)
{
g_return_if_fail (cogl_is_primitive (primitive));
primitive->first_vertex = first_vertex;
}
int
cogl_primitive_get_n_vertices (CoglPrimitive *primitive)
{
g_return_val_if_fail (cogl_is_primitive (primitive), 0);
return primitive->n_vertices;
}
void
cogl_primitive_set_n_vertices (CoglPrimitive *primitive,
int n_vertices)
{
g_return_if_fail (cogl_is_primitive (primitive));
primitive->n_vertices = n_vertices;
}
CoglVerticesMode
cogl_primitive_get_mode (CoglPrimitive *primitive)
{
g_return_val_if_fail (cogl_is_primitive (primitive), 0);
return primitive->mode;
}
void
cogl_primitive_set_mode (CoglPrimitive *primitive,
CoglVerticesMode mode)
{
g_return_if_fail (cogl_is_primitive (primitive));
primitive->mode = mode;
}
void
cogl_primitive_set_indices (CoglPrimitive *primitive,
CoglIndices *indices)
{
g_return_if_fail (cogl_is_primitive (primitive));
if (indices)
cogl_object_ref (indices);
if (primitive->indices)
cogl_object_unref (primitive->indices);
primitive->indices = indices;
}
/* XXX: cogl_draw_primitive() ? */
void
cogl_primitive_draw (CoglPrimitive *primitive)
{
CoglVertexAttribute **attributes =
(CoglVertexAttribute **)primitive->attributes->data;
if (primitive->indices)
cogl_draw_indexed_vertex_attributes_array (primitive->mode,
primitive->first_vertex,
primitive->n_vertices,
primitive->indices,
attributes);
else
cogl_draw_vertex_attributes_array (primitive->mode,
primitive->first_vertex,
primitive->n_vertices,
attributes);
}