mutter/cogl/cogl-util.c
Robert Bragg a0441778ad This re-licenses Cogl 1.18 under the MIT license
Since the Cogl 1.18 branch is actively maintained in parallel with the
master branch; this is a counter part to commit 1b83ef938fc16b which
re-licensed the master branch to use the MIT license.

This re-licensing is a follow up to the proposal that was sent to the
Cogl mailing list:
http://lists.freedesktop.org/archives/cogl/2013-December/001465.html

Note: there was a copyright assignment policy in place for Clutter (and
therefore Cogl which was part of Clutter at the time) until the 11th of
June 2010 and so we only checked the details after that point (commit
0bbf50f905)

For each file, authors were identified via this Git command:
$ git blame -p -C -C -C20 -M -M10  0bbf50f905..HEAD

We received blanket approvals for re-licensing all Red Hat and Collabora
contributions which reduced how many people needed to be contacted
individually:
- http://lists.freedesktop.org/archives/cogl/2013-December/001470.html
- http://lists.freedesktop.org/archives/cogl/2014-January/001536.html

Individual approval requests were sent to all the other identified authors
who all confirmed the re-license on the Cogl mailinglist:
http://lists.freedesktop.org/archives/cogl/2014-January

As well as updating the copyright header in all sources files, the
COPYING file has been updated to reflect the license change and also
document the other licenses used in Cogl such as the SGI Free Software
License B, version 2.0 and the 3-clause BSD license.

This patch was not simply cherry-picked from master; but the same
methodology was used to check the source files.
2014-02-22 02:02:53 +00:00

287 lines
8.5 KiB
C

/*
* Cogl
*
* A Low Level GPU Graphics and Utilities API
*
* Copyright (C) 2007,2008,2009,2010 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "cogl-util.h"
#include "cogl-private.h"
/*
* cogl_util_next_p2:
* @a: Value to get the next power of two
*
* Calculates the next power of two greater than or equal to @a.
*
* Return value: @a if @a is already a power of two, otherwise returns
* the next nearest power of two.
*/
int
_cogl_util_next_p2 (int a)
{
int rval = 1;
while (rval < a)
rval <<= 1;
return rval;
}
unsigned int
_cogl_util_one_at_a_time_mix (unsigned int hash)
{
hash += ( hash << 3 );
hash ^= ( hash >> 11 );
hash += ( hash << 15 );
return hash;
}
/* The 'ffs' function is part of C99 so it isn't always available */
#ifndef HAVE_FFS
int
_cogl_util_ffs (int num)
{
int i = 1;
if (num == 0)
return 0;
while ((num & 1) == 0)
{
num >>= 1;
i++;
}
return i;
}
#endif /* HAVE_FFS */
/* The 'ffsl' is non-standard but when building with GCC we'll use its
builtin instead */
#ifndef COGL_UTIL_HAVE_BUILTIN_FFSL
int
_cogl_util_ffsl_wrapper (long int num)
{
int i = 1;
if (num == 0)
return 0;
while ((num & 1) == 0)
{
num >>= 1;
i++;
}
return i;
}
#endif /* COGL_UTIL_HAVE_BUILTIN_FFSL */
#ifndef COGL_UTIL_HAVE_BUILTIN_POPCOUNTL
const unsigned char
_cogl_util_popcount_table[256] =
{
0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, 1, 2, 2, 3, 2, 3, 3, 4,
2, 3, 3, 4, 3, 4, 4, 5, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 1, 2, 2, 3, 2, 3, 3, 4,
2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6,
4, 5, 5, 6, 5, 6, 6, 7, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4, 3, 4, 4, 5,
3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6,
4, 5, 5, 6, 5, 6, 6, 7, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
};
#endif /* COGL_UTIL_HAVE_BUILTIN_POPCOUNTL */
/* tests/conform/test-bitmask.c tests some cogl internals and includes this
* file directly but since these functions depend on other internal Cogl
* symbols we hide them from test-bitmask.c
*
* XXX: maybe there's a better way for us to handle internal testing
* to avoid needing hacks like this.
*/
#ifndef _COGL_IN_TEST_BITMASK
/* Given a set of red, green and blue component masks, a depth and
* bits per pixel this function tries to determine a corresponding
* CoglPixelFormat.
*
* The depth is measured in bits not including padding for un-used
* alpha. The bits per pixel (bpp) does include padding for un-used
* alpha.
*
* This function firstly aims to match formats with RGB ordered
* components and only considers alpha coming first, in the most
* significant bits. If the function fails to match then it recurses
* by either switching the r and b masks around to check for BGR
* ordered formats or it recurses with the masks shifted to check for
* formats where the alpha component is the least significant bits.
*/
static CoglPixelFormat
_cogl_util_pixel_format_from_masks_real (unsigned long r_mask,
unsigned long g_mask,
unsigned long b_mask,
int depth, int bpp,
CoglBool check_bgr,
CoglBool check_afirst,
int recursion_depth)
{
CoglPixelFormat image_format;
if (depth == 24 && bpp == 24 &&
r_mask == 0xff0000 && g_mask == 0xff00 && b_mask == 0xff)
{
return COGL_PIXEL_FORMAT_RGB_888;
}
else if ((depth == 24 || depth == 32) && bpp == 32 &&
r_mask == 0xff0000 && g_mask == 0xff00 && b_mask == 0xff)
{
return COGL_PIXEL_FORMAT_ARGB_8888_PRE;
}
else if ((depth == 30 || depth == 32) &&
r_mask == 0x3ff00000 && g_mask == 0xffc00 && b_mask == 0x3ff)
{
return COGL_PIXEL_FORMAT_ARGB_2101010_PRE;
}
else if (depth == 16 && bpp == 16 &&
r_mask == 0xf800 && g_mask == 0x7e0 && b_mask == 0x1f)
{
return COGL_PIXEL_FORMAT_RGB_565;
}
if (recursion_depth == 2)
return 0;
/* Check for BGR ordering if we didn't find a match */
if (check_bgr)
{
image_format =
_cogl_util_pixel_format_from_masks_real (b_mask, g_mask, r_mask,
depth, bpp,
FALSE,
TRUE,
recursion_depth + 1);
if (image_format)
return image_format ^ COGL_BGR_BIT;
}
/* Check for alpha in the least significant bits if we still
* haven't found a match... */
if (check_afirst && depth != bpp)
{
int shift = bpp - depth;
image_format =
_cogl_util_pixel_format_from_masks_real (r_mask >> shift,
g_mask >> shift,
b_mask >> shift,
depth, bpp,
TRUE,
FALSE,
recursion_depth + 1);
if (image_format)
return image_format ^ COGL_AFIRST_BIT;
}
return 0;
}
CoglPixelFormat
_cogl_util_pixel_format_from_masks (unsigned long r_mask,
unsigned long g_mask,
unsigned long b_mask,
int depth, int bpp,
CoglBool byte_order_is_lsb_first)
{
CoglPixelFormat image_format =
_cogl_util_pixel_format_from_masks_real (r_mask, g_mask, b_mask,
depth, bpp,
TRUE,
TRUE,
0);
if (!image_format)
{
const char *byte_order[] = { "MSB first", "LSB first" };
g_warning ("Could not find a matching pixel format for red mask=0x%lx,"
"green mask=0x%lx, blue mask=0x%lx at depth=%d, bpp=%d "
"and byte order=%s\n", r_mask, g_mask, b_mask, depth, bpp,
byte_order[!!byte_order_is_lsb_first]);
return 0;
}
/* If the image is in little-endian then the order in memory is
reversed */
if (byte_order_is_lsb_first &&
_cogl_pixel_format_is_endian_dependant (image_format))
{
image_format ^= COGL_BGR_BIT;
if (image_format & COGL_A_BIT)
image_format ^= COGL_AFIRST_BIT;
}
return image_format;
}
#ifndef HAVE_MEMMEM
char *
_cogl_util_memmem (const void *haystack,
size_t haystack_len,
const void *needle,
size_t needle_len)
{
size_t i;
if (needle_len > haystack_len)
return NULL;
for (i = 0; i <= haystack_len - needle_len; i++)
if (!memcmp ((const char *) haystack + i, needle, needle_len))
return (char *) haystack + i;
return NULL;
}
#endif /* HAVE_MEMMEM */
#endif /* _COGL_IN_TEST_BITMASK */