mutter/cogl/cogl-indices.c
Robert Bragg b72f255c0a Start to reduce dependence on glib
Since we've had several developers from admirable projects say they
would like to use Cogl but would really prefer not to pull in
gobject,gmodule and glib as extra dependencies we are investigating if
we can get to the point where glib is only an optional dependency.
Actually we feel like we only make minimal use of glib anyway, so it may
well be quite straightforward to achieve this.

This adds a --disable-glib configure option that can be used to disable
features that depend on glib.

Actually --disable-glib doesn't strictly disable glib at this point
because it's more helpful if cogl continues to build as we make
incremental progress towards this.

The first use of glib that this patch tackles is the use of
g_return_val_if_fail and g_return_if_fail which have been replaced with
equivalent _COGL_RETURN_VAL_IF_FAIL and _COGL_RETURN_IF_FAIL macros.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-11-01 12:03:02 +00:00

255 lines
6.6 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>
* Neil Roberts <neil@linux.intel.com>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl-util.h"
#include "cogl-object-private.h"
#include "cogl-context-private.h"
#include "cogl-indices.h"
#include "cogl-indices-private.h"
#include "cogl-index-buffer.h"
#include <stdarg.h>
static void _cogl_indices_free (CoglIndices *indices);
COGL_OBJECT_DEFINE (Indices, indices);
static size_t
sizeof_indices_type (CoglIndicesType type)
{
switch (type)
{
case COGL_INDICES_TYPE_UNSIGNED_BYTE:
return 1;
case COGL_INDICES_TYPE_UNSIGNED_SHORT:
return 2;
case COGL_INDICES_TYPE_UNSIGNED_INT:
return 4;
}
g_return_val_if_reached (0);
}
CoglIndices *
cogl_indices_new_for_buffer (CoglIndicesType type,
CoglIndexBuffer *buffer,
gsize offset)
{
CoglIndices *indices = g_slice_new (CoglIndices);
indices->buffer = cogl_object_ref (buffer);
indices->offset = offset;
indices->type = type;
indices->immutable_ref = 0;
return _cogl_indices_object_new (indices);
}
CoglIndices *
cogl_indices_new (CoglIndicesType type,
const void *indices_data,
int n_indices)
{
size_t buffer_bytes = sizeof_indices_type (type) * n_indices;
CoglIndexBuffer *index_buffer = cogl_index_buffer_new (buffer_bytes);
CoglBuffer *buffer = COGL_BUFFER (index_buffer);
CoglIndices *indices;
cogl_buffer_set_data (buffer,
0,
indices_data,
buffer_bytes);
indices = cogl_indices_new_for_buffer (type, index_buffer, 0);
cogl_object_unref (index_buffer);
return indices;
}
CoglIndexBuffer *
cogl_indices_get_buffer (CoglIndices *indices)
{
return indices->buffer;
}
CoglIndicesType
cogl_indices_get_type (CoglIndices *indices)
{
_COGL_RETURN_VAL_IF_FAIL (cogl_is_indices (indices),
COGL_INDICES_TYPE_UNSIGNED_BYTE);
return indices->type;
}
gsize
cogl_indices_get_offset (CoglIndices *indices)
{
_COGL_RETURN_VAL_IF_FAIL (cogl_is_indices (indices), 0);
return indices->offset;
}
static void
warn_about_midscene_changes (void)
{
static gboolean seen = FALSE;
if (!seen)
{
g_warning ("Mid-scene modification of indices has "
"undefined results\n");
seen = TRUE;
}
}
void
cogl_indices_set_offset (CoglIndices *indices,
gsize offset)
{
_COGL_RETURN_IF_FAIL (cogl_is_indices (indices));
if (G_UNLIKELY (indices->immutable_ref))
warn_about_midscene_changes ();
indices->offset = offset;
}
static void
_cogl_indices_free (CoglIndices *indices)
{
cogl_object_unref (indices->buffer);
g_slice_free (CoglIndices, indices);
}
CoglIndices *
_cogl_indices_immutable_ref (CoglIndices *indices)
{
_COGL_RETURN_VAL_IF_FAIL (cogl_is_indices (indices), NULL);
indices->immutable_ref++;
_cogl_buffer_immutable_ref (COGL_BUFFER (indices->buffer));
return indices;
}
void
_cogl_indices_immutable_unref (CoglIndices *indices)
{
_COGL_RETURN_IF_FAIL (cogl_is_indices (indices));
_COGL_RETURN_IF_FAIL (indices->immutable_ref > 0);
indices->immutable_ref--;
_cogl_buffer_immutable_unref (COGL_BUFFER (indices->buffer));
}
CoglIndices *
cogl_get_rectangle_indices (int n_rectangles)
{
int n_indices = n_rectangles * 6;
_COGL_GET_CONTEXT (ctx, NULL);
/* Check if the largest index required will fit in a byte array... */
if (n_indices <= 256 / 4 * 6)
{
/* Generate the byte array if we haven't already */
if (ctx->rectangle_byte_indices == NULL)
{
guint8 *byte_array = g_malloc (256 / 4 * 6 * sizeof (guint8));
guint8 *p = byte_array;
int i, vert_num = 0;
for (i = 0; i < 256 / 4; i++)
{
*(p++) = vert_num + 0;
*(p++) = vert_num + 1;
*(p++) = vert_num + 2;
*(p++) = vert_num + 0;
*(p++) = vert_num + 2;
*(p++) = vert_num + 3;
vert_num += 4;
}
ctx->rectangle_byte_indices
= cogl_indices_new (COGL_INDICES_TYPE_UNSIGNED_BYTE,
byte_array,
256 / 4 * 6);
g_free (byte_array);
}
return ctx->rectangle_byte_indices;
}
else
{
if (ctx->rectangle_short_indices_len < n_indices)
{
guint16 *short_array;
guint16 *p;
int i, vert_num = 0;
if (ctx->rectangle_short_indices != NULL)
cogl_object_unref (ctx->rectangle_short_indices);
/* Pick a power of two >= MAX (512, n_indices) */
if (ctx->rectangle_short_indices_len == 0)
ctx->rectangle_short_indices_len = 512;
while (ctx->rectangle_short_indices_len < n_indices)
ctx->rectangle_short_indices_len *= 2;
/* Over-allocate to generate a whole number of quads */
p = short_array = g_malloc ((ctx->rectangle_short_indices_len
+ 5) / 6 * 6
* sizeof (guint16));
/* Fill in the complete quads */
for (i = 0; i < ctx->rectangle_short_indices_len; i += 6)
{
*(p++) = vert_num + 0;
*(p++) = vert_num + 1;
*(p++) = vert_num + 2;
*(p++) = vert_num + 0;
*(p++) = vert_num + 2;
*(p++) = vert_num + 3;
vert_num += 4;
}
ctx->rectangle_short_indices
= cogl_indices_new (COGL_INDICES_TYPE_UNSIGNED_SHORT,
short_array,
ctx->rectangle_short_indices_len);
g_free (short_array);
}
return ctx->rectangle_short_indices;
}
}