mutter/cogl/cogl-bitmap-fallback.c
Robert Bragg 0f5f4e8645 cogl: improves header and coding style consistency
We've had complaints that our Cogl code/headers are a bit "special" so
this is a first pass at tidying things up by giving them some
consistency. These changes are all consistent with how new code in Cogl
is being written, but the style isn't consistently applied across all
code yet.

There are two parts to this patch; but since each one required a large
amount of effort to maintain tidy indenting it made sense to combine the
changes to reduce the time spent re indenting the same lines.

The first change is to use a consistent style for declaring function
prototypes in headers. Cogl headers now consistently use this style for
prototypes:

 return_type
 cogl_function_name (CoglType arg0,
                     CoglType arg1);

Not everyone likes this style, but it seems that most of the currently
active Cogl developers agree on it.

The second change is to constrain the use of redundant glib data types
in Cogl. Uses of gint, guint, gfloat, glong, gulong and gchar have all
been replaced with int, unsigned int, float, long, unsigned long and char
respectively. When talking about pixel data; use of guchar has been
replaced with guint8, otherwise unsigned char can be used.

The glib types that we continue to use for portability are gboolean,
gint{8,16,32,64}, guint{8,16,32,64} and gsize.

The general intention is that Cogl should look palatable to the widest
range of C programmers including those outside the Gnome community so
- especially for the public API - we want to minimize the number of
foreign looking typedefs.
2010-02-12 14:05:00 +00:00

533 lines
13 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-internal.h"
#include "cogl-bitmap-private.h"
#include <string.h>
/* TO rgba */
inline static void
_cogl_g_to_rgba (const guint8 *src, guint8 *dst)
{
dst[0] = src[0];
dst[1] = src[0];
dst[2] = src[0];
dst[3] = 255;
}
inline static void
_cogl_rgb_to_rgba (const guint8 *src, guint8 *dst)
{
dst[0] = src[0];
dst[1] = src[1];
dst[2] = src[2];
dst[3] = 255;
}
inline static void
_cogl_bgr_to_rgba (const guint8 *src, guint8 *dst)
{
dst[0] = src[2];
dst[1] = src[1];
dst[2] = src[0];
dst[3] = 255;
}
inline static void
_cogl_bgra_to_rgba (const guint8 *src, guint8 *dst)
{
dst[0] = src[2];
dst[1] = src[1];
dst[2] = src[0];
dst[3] = src[3];
}
inline static void
_cogl_argb_to_rgba (const guint8 *src, guint8 *dst)
{
dst[0] = src[1];
dst[1] = src[2];
dst[2] = src[3];
dst[3] = src[0];
}
inline static void
_cogl_abgr_to_rgba (const guint8 *src, guint8 *dst)
{
dst[0] = src[3];
dst[1] = src[2];
dst[2] = src[1];
dst[3] = src[0];
}
inline static void
_cogl_rgba_to_rgba (const guint8 *src, guint8 *dst)
{
dst[0] = src[0];
dst[1] = src[1];
dst[2] = src[2];
dst[3] = src[3];
}
/* FROM rgba */
inline static void
_cogl_rgba_to_g (const guint8 *src, guint8 *dst)
{
dst[0] = (src[0] + src[1] + src[2]) / 3;
}
inline static void
_cogl_rgba_to_rgb (const guint8 *src, guint8 *dst)
{
dst[0] = src[0];
dst[1] = src[1];
dst[2] = src[2];
}
inline static void
_cogl_rgba_to_bgr (const guint8 *src, guint8 *dst)
{
dst[0] = src[2];
dst[1] = src[1];
dst[2] = src[0];
}
inline static void
_cogl_rgba_to_bgra (const guint8 *src, guint8 *dst)
{
dst[0] = src[2];
dst[1] = src[1];
dst[2] = src[0];
dst[3] = src[3];
}
inline static void
_cogl_rgba_to_argb (const guint8 *src, guint8 *dst)
{
dst[0] = src[3];
dst[1] = src[0];
dst[2] = src[1];
dst[3] = src[2];
}
inline static void
_cogl_rgba_to_abgr (const guint8 *src, guint8 *dst)
{
dst[0] = src[3];
dst[1] = src[2];
dst[2] = src[1];
dst[3] = src[0];
}
/* (Un)Premultiplication */
inline static void
_cogl_unpremult_alpha_0 (guint8 *dst)
{
dst[0] = 0;
dst[1] = 0;
dst[2] = 0;
dst[3] = 0;
}
inline static void
_cogl_unpremult_alpha_last (guint8 *dst)
{
guint8 alpha = dst[3];
dst[0] = (dst[0] * 255) / alpha;
dst[1] = (dst[1] * 255) / alpha;
dst[2] = (dst[2] * 255) / alpha;
}
inline static void
_cogl_unpremult_alpha_first (guint8 *dst)
{
guint8 alpha = dst[0];
dst[1] = (dst[1] * 255) / alpha;
dst[2] = (dst[2] * 255) / alpha;
dst[3] = (dst[3] * 255) / alpha;
}
/* No division form of floor((c*a + 128)/255) (I first encountered
* this in the RENDER implementation in the X server.) Being exact
* is important for a == 255 - we want to get exactly c.
*/
#define MULT(d,a,t) \
G_STMT_START { \
t = d * a + 128; \
d = ((t >> 8) + t) >> 8; \
} G_STMT_END
inline static void
_cogl_premult_alpha_last (guint8 *dst)
{
guint8 alpha = dst[3];
/* Using a separate temporary per component has given slightly better
* code generation with GCC in the past; it shouldn't do any worse in
* any case.
*/
unsigned int t1, t2, t3;
MULT(dst[0], alpha, t1);
MULT(dst[1], alpha, t2);
MULT(dst[2], alpha, t3);
}
inline static void
_cogl_premult_alpha_first (guint8 *dst)
{
guint8 alpha = dst[0];
unsigned int t1, t2, t3;
MULT(dst[1], alpha, t1);
MULT(dst[2], alpha, t2);
MULT(dst[3], alpha, t3);
}
#undef MULT
/* Use the SSE optimized version to premult four pixels at once when
it is available. The same assembler code works for x86 and x86-64
because it doesn't refer to any non-SSE registers directly */
#if defined(__SSE2__) && defined(__GNUC__) \
&& (defined(__x86_64) || defined(__i386))
#define COGL_USE_PREMULT_SSE2
#endif
#ifdef COGL_USE_PREMULT_SSE2
inline static void
_cogl_premult_alpha_last_four_pixels_sse2 (guint8 *p)
{
/* 8 copies of 128 used below */
static const gint16 eight_halves[8] __attribute__ ((aligned (16))) =
{ 128, 128, 128, 128, 128, 128, 128, 128 };
/* Mask of the rgb components of the four pixels */
static const gint8 just_rgb[16] __attribute__ ((aligned (16))) =
{ 0xff, 0xff, 0xff, 0x00, 0xff, 0xff, 0xff, 0x00,
0xff, 0xff, 0xff, 0x00, 0xff, 0xff, 0xff, 0x00 };
/* Each SSE register only holds two pixels because we need to work
with 16-bit intermediate values. We still do four pixels by
interleaving two registers in the hope that it will pipeline
better */
asm (/* Load eight_halves into xmm5 for later */
"movdqa (%1), %%xmm5\n"
/* Clear xmm3 */
"pxor %%xmm3, %%xmm3\n"
/* Load two pixels from p into the low half of xmm0 */
"movlps (%0), %%xmm0\n"
/* Load the next set of two pixels from p into the low half of xmm1 */
"movlps 8(%0), %%xmm1\n"
/* Unpack 8 bytes from the low quad-words in each register to 8
16-bit values */
"punpcklbw %%xmm3, %%xmm0\n"
"punpcklbw %%xmm3, %%xmm1\n"
/* Copy alpha values of the first pixel in xmm0 to all
components of the first pixel in xmm2 */
"pshuflw $255, %%xmm0, %%xmm2\n"
/* same for xmm1 and xmm3 */
"pshuflw $255, %%xmm1, %%xmm3\n"
/* The above also copies the second pixel directly so we now
want to replace the RGB components with copies of the alpha
components */
"pshufhw $255, %%xmm2, %%xmm2\n"
"pshufhw $255, %%xmm3, %%xmm3\n"
/* Multiply the rgb components by the alpha */
"pmullw %%xmm2, %%xmm0\n"
"pmullw %%xmm3, %%xmm1\n"
/* Add 128 to each component */
"paddw %%xmm5, %%xmm0\n"
"paddw %%xmm5, %%xmm1\n"
/* Copy the results to temporary registers xmm4 and xmm5 */
"movdqa %%xmm0, %%xmm4\n"
"movdqa %%xmm1, %%xmm5\n"
/* Divide the results by 256 */
"psrlw $8, %%xmm0\n"
"psrlw $8, %%xmm1\n"
/* Add the temporaries back in */
"paddw %%xmm4, %%xmm0\n"
"paddw %%xmm5, %%xmm1\n"
/* Divide again */
"psrlw $8, %%xmm0\n"
"psrlw $8, %%xmm1\n"
/* Pack the results back as bytes */
"packuswb %%xmm1, %%xmm0\n"
/* Load just_rgb into xmm3 for later */
"movdqa (%2), %%xmm3\n"
/* Reload all four pixels into xmm2 */
"movups (%0), %%xmm2\n"
/* Mask out the alpha from the results */
"andps %%xmm3, %%xmm0\n"
/* Mask out the RGB from the original four pixels */
"andnps %%xmm2, %%xmm3\n"
/* Combine the two to get the right alpha values */
"orps %%xmm3, %%xmm0\n"
/* Write to memory */
"movdqu %%xmm0, (%0)\n"
: /* no outputs */
: "r" (p), "r" (eight_halves), "r" (just_rgb)
: "xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5");
}
#endif /* COGL_USE_PREMULT_SSE2 */
gboolean
_cogl_bitmap_fallback_can_convert (CoglPixelFormat src, CoglPixelFormat dst)
{
if (src == dst)
return FALSE;
switch (src & COGL_UNORDERED_MASK)
{
case COGL_PIXEL_FORMAT_G_8:
case COGL_PIXEL_FORMAT_24:
case COGL_PIXEL_FORMAT_32:
if ((dst & COGL_UNORDERED_MASK) != COGL_PIXEL_FORMAT_24 &&
(dst & COGL_UNORDERED_MASK) != COGL_PIXEL_FORMAT_32 &&
(dst & COGL_UNORDERED_MASK) != COGL_PIXEL_FORMAT_G_8)
return FALSE;
break;
default:
return FALSE;
}
return TRUE;
}
gboolean
_cogl_bitmap_fallback_can_unpremult (CoglPixelFormat format)
{
return ((format & COGL_UNORDERED_MASK) == COGL_PIXEL_FORMAT_32);
}
gboolean
_cogl_bitmap_fallback_can_premult (CoglPixelFormat format)
{
return ((format & COGL_UNORDERED_MASK) == COGL_PIXEL_FORMAT_32);
}
gboolean
_cogl_bitmap_fallback_convert (const CoglBitmap *bmp,
CoglBitmap *dst_bmp,
CoglPixelFormat dst_format)
{
guint8 *src;
guint8 *dst;
int src_bpp;
int dst_bpp;
int x,y;
guint8 temp_rgba[4] = {0,0,0,0};
/* Make sure conversion supported */
if (!_cogl_bitmap_fallback_can_convert (bmp->format, dst_format))
return FALSE;
src_bpp = _cogl_get_format_bpp (bmp->format);
dst_bpp = _cogl_get_format_bpp (dst_format);
/* Initialize destination bitmap */
*dst_bmp = *bmp;
dst_bmp->rowstride = sizeof(guint8) * dst_bpp * dst_bmp->width;
dst_bmp->format = ((bmp->format & COGL_PREMULT_BIT) |
(dst_format & COGL_UNPREMULT_MASK));
/* Allocate a new buffer to hold converted data */
dst_bmp->data = g_malloc (sizeof(guint8)
* dst_bmp->height
* dst_bmp->rowstride);
/* FIXME: Optimize */
for (y = 0; y < bmp->height; y++)
{
src = (guint8*)bmp->data + y * bmp->rowstride;
dst = (guint8*)dst_bmp->data + y * dst_bmp->rowstride;
for (x = 0; x < bmp->width; x++)
{
/* FIXME: Would be nice to at least remove this inner
* branching, but not sure it can be done without
* rewriting of the whole loop */
switch (bmp->format & COGL_UNPREMULT_MASK)
{
case COGL_PIXEL_FORMAT_G_8:
_cogl_g_to_rgba (src, temp_rgba); break;
case COGL_PIXEL_FORMAT_RGB_888:
_cogl_rgb_to_rgba (src, temp_rgba); break;
case COGL_PIXEL_FORMAT_BGR_888:
_cogl_bgr_to_rgba (src, temp_rgba); break;
case COGL_PIXEL_FORMAT_RGBA_8888:
_cogl_rgba_to_rgba (src, temp_rgba); break;
case COGL_PIXEL_FORMAT_BGRA_8888:
_cogl_bgra_to_rgba (src, temp_rgba); break;
case COGL_PIXEL_FORMAT_ARGB_8888:
_cogl_argb_to_rgba (src, temp_rgba); break;
case COGL_PIXEL_FORMAT_ABGR_8888:
_cogl_abgr_to_rgba (src, temp_rgba); break;
default:
break;
}
switch (dst_format & COGL_UNPREMULT_MASK)
{
case COGL_PIXEL_FORMAT_G_8:
_cogl_rgba_to_g (temp_rgba, dst); break;
case COGL_PIXEL_FORMAT_RGB_888:
_cogl_rgba_to_rgb (temp_rgba, dst); break;
case COGL_PIXEL_FORMAT_BGR_888:
_cogl_rgba_to_bgr (temp_rgba, dst); break;
case COGL_PIXEL_FORMAT_RGBA_8888:
_cogl_rgba_to_rgba (temp_rgba, dst); break;
case COGL_PIXEL_FORMAT_BGRA_8888:
_cogl_rgba_to_bgra (temp_rgba, dst); break;
case COGL_PIXEL_FORMAT_ARGB_8888:
_cogl_rgba_to_argb (temp_rgba, dst); break;
case COGL_PIXEL_FORMAT_ABGR_8888:
_cogl_rgba_to_abgr (temp_rgba, dst); break;
default:
break;
}
src += src_bpp;
dst += dst_bpp;
}
}
return TRUE;
}
gboolean
_cogl_bitmap_fallback_unpremult (CoglBitmap *bmp)
{
guint8 *p;
int x,y;
/* Make sure format supported for un-premultiplication */
if (!_cogl_bitmap_fallback_can_unpremult (bmp->format))
return FALSE;
for (y = 0; y < bmp->height; y++)
{
p = (guint8*) bmp->data + y * bmp->rowstride;
if (bmp->format & COGL_AFIRST_BIT)
{
for (x = 0; x < bmp->width; x++)
{
if (p[0] == 0)
_cogl_unpremult_alpha_0 (p);
else
_cogl_unpremult_alpha_first (p);
p += 4;
}
}
else
{
for (x = 0; x < bmp->width; x++)
{
if (p[3] == 0)
_cogl_unpremult_alpha_0 (p);
else
_cogl_unpremult_alpha_last (p);
p += 4;
}
}
}
bmp->format &= ~COGL_PREMULT_BIT;
return TRUE;
}
gboolean
_cogl_bitmap_fallback_premult (CoglBitmap *bmp)
{
guint8 *p;
int x,y;
/* Make sure format supported for un-premultiplication */
if (!_cogl_bitmap_fallback_can_premult (bmp->format))
return FALSE;
for (y = 0; y < bmp->height; y++)
{
p = (guint8*) bmp->data + y * bmp->rowstride;
if (bmp->format & COGL_AFIRST_BIT)
{
for (x = 0; x < bmp->width; x++)
{
_cogl_premult_alpha_first (p);
p += 4;
}
}
else
{
x = bmp->width;
#ifdef COGL_USE_PREMULT_SSE2
/* Process 4 pixels at a time */
while (x >= 4)
{
_cogl_premult_alpha_last_four_pixels_sse2 (p);
p += 4 * 4;
x -= 4;
}
/* If there are any pixels left we will fall through and
handle them below */
#endif /* COGL_USE_PREMULT_SSE2 */
while (x-- > 0)
{
_cogl_premult_alpha_last (p);
p += 4;
}
}
}
bmp->format |= COGL_PREMULT_BIT;
return TRUE;
}
gboolean
_cogl_bitmap_fallback_from_file (CoglBitmap *bmp,
const char *filename)
{
/* FIXME: use jpeglib, libpng, etc. manually maybe */
return FALSE;
}