root/trunk/third/nautilus/libnautilus-extensions/bug-5712-pr3-workaround--gdk-pixbuf-drawable.c @ 15547

/* FIXME bugzilla.eazel.com 5813:
 * As soon as gtk 1.2.9 is released, this hack needs to be exorcised.
 */

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* GdkPixbuf library - convert X drawable information to RGB
 *
 * Copyright (C) 1999 Michael Zucchi
 *
 * Authors: Michael Zucchi <zucchi@zedzone.mmc.com.au>
 *          Cody Russell <bratsche@gnome.org>
 *          Federico Mena-Quintero <federico@gimp.org>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library 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.
 */

#include <config.h>
#include <stdio.h>
#include <string.h>
#include "bug-5712-pr3-workaround--gdk-pixbuf-private.h"

#if (G_BYTE_ORDER == G_LITTLE_ENDIAN)
#define LITTLE
#endif
#define d(x)



static guint32 mask_table[] = {
        0x00000000, 0x00000001, 0x00000003, 0x00000007,
        0x0000000f, 0x0000001f, 0x0000003f, 0x0000007f,
        0x000000ff, 0x000001ff, 0x000003ff, 0x000007ff,
        0x00000fff, 0x00001fff, 0x00003fff, 0x00007fff,
        0x0000ffff, 0x0001ffff, 0x0003ffff, 0x0007ffff,
        0x000fffff, 0x001fffff, 0x003fffff, 0x007fffff,
        0x00ffffff, 0x01ffffff, 0x03ffffff, 0x07ffffff,
        0x0fffffff, 0x1fffffff, 0x3fffffff, 0x7fffffff,
        0xffffffff
};



/*
  convert 1 bits-pixel data
  no alpha
*/
static void
rgb1 (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;
        guint8 *s;
        register guint8 data;
        guint8 *o;
        guint8 *srow = image->mem, *orow = pixels;

        d (printf ("1 bits/pixel\n"));

        /* convert upto 8 pixels/time */
        /* its probably not worth trying to make this run very fast, who uses
           1 bit displays anymore? */
        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = orow;

                for (xx = 0; xx < width; xx ++) {
                        data = srow[xx >> 3] >> (7 - (xx & 7)) & 1;
                        *o++ = colormap->colors[data].red;
                        *o++ = colormap->colors[data].green;
                        *o++ = colormap->colors[data].blue;
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 1 bits/pixel data
  with alpha
*/
static void
rgb1a (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;
        guint8 *s;
        register guint8 data;
        guint8 *o;
        guint8 *srow = image->mem, *orow = pixels;
        guint32 remap[2];

        d (printf ("1 bits/pixel\n"));

        /* convert upto 8 pixels/time */
        /* its probably not worth trying to make this run very fast, who uses
           1 bit displays anymore? */
        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (xx = 0; xx < 2; xx++) {
#ifdef LITTLE
                remap[xx] = 0xff000000
                        | colormap->colors[xx].blue << 16
                        | colormap->colors[xx].green << 8
                        | colormap->colors[xx].red;
#else
                remap[xx] = 0xff
                        | colormap->colors[xx].red << 24
                        | colormap->colors[xx].green << 16
                        | colormap->colors[xx].blue << 8;
#endif
        }

        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = orow;

                for (xx = 0; xx < width; xx ++) {
                        data = srow[xx >> 3] >> (7 - (xx & 7)) & 1;
                        *o++ = remap[data];
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 8 bits/pixel data
  no alpha
*/
static void
rgb8 (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;
        guint32 mask;
        register guint32 data;
        guint8 *srow = image->mem, *orow = pixels;
        register guint8 *s;
        register guint8 *o;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        d (printf ("8 bit, no alpha output\n"));

        mask = mask_table[image->depth];

        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = orow;
                for (xx = 0; xx < width; xx++) {
                        data = *s++ & mask;
                        *o++ = colormap->colors[data].red;
                        *o++ = colormap->colors[data].green;
                        *o++ = colormap->colors[data].blue;
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 8 bits/pixel data
  with alpha
*/
static void
rgb8a (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;
        guint32 mask;
        register guint32 data;
        guint32 remap[256];
        register guint8 *s;     /* read 2 pixels at once */
        register guint32 *o;
        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        d (printf ("8 bit, with alpha output\n"));

        mask = mask_table[image->depth];

        for (xx = 0; xx < colormap->size; xx++) {
#ifdef LITTLE
                remap[xx] = 0xff000000
                        | colormap->colors[xx].blue << 16
                        | colormap->colors[xx].green << 8
                        | colormap->colors[xx].red;
#else
                remap[xx] = 0xff
                        | colormap->colors[xx].red << 24
                        | colormap->colors[xx].green << 16
                        | colormap->colors[xx].blue << 8;
#endif
        }

        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = (guint32 *) orow;
                for (xx = 0; xx < width; xx ++) {
                        data = *s++ & mask;
                        *o++ = remap[data];
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 16 bits/pixel data
  no alpha
  data in lsb format
*/
static void
rgb565lsb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

#ifdef LITTLE
        register guint32 *s;    /* read 2 pixels at once */
#else
        register guint8 *s;     /* read 2 pixels at once */
#endif
        register guint16 *o;
        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
#ifdef LITTLE
                s = (guint32 *) srow;
#else
                s = srow;
#endif
                o = (guint16 *) orow;
                for (xx = 1; xx < width; xx += 2) {
                        register guint32 data;
#ifdef LITTLE
                        data = *s++;
                        *o++ = (data & 0xf800) >> 8 | (data & 0xe000) >> 13
                                | (data & 0x7e0) << 5 | (data & 0x600) >> 1;
                        *o++ = (data & 0x1f) << 3 | (data & 0x1c) >> 2
                                | (data & 0xf8000000) >> 16 | (data & 0xe0000000) >> 21;
                        *o++ = (data & 0x7e00000) >> 19 | (data & 0x6000000) >> 25
                                | (data & 0x1f0000) >> 5 | (data & 0x1c0000) >> 10;
#else
                        /* swap endianness first */
                        data = s[0] | s[1] << 8 | s[2] << 16 | s[3] << 24;
                        s += 4;
                        *o++ = (data & 0xf800) | (data & 0xe000) >> 5
                                | (data & 0x7e0) >> 3 | (data & 0x600) >> 9;
                        *o++ = (data & 0x1f) << 11 | (data & 0x1c) << 6
                                | (data & 0xf8000000) >> 24 | (data & 0xe0000000) >> 29;
                        *o++ = (data & 0x7e00000) >> 11 | (data & 0x6000000) >> 17
                                | (data & 0x1f0000) >> 13 | (data & 0x1c0000) >> 18;
#endif
                }
                /* check for last remaining pixel */
                if (width & 1) {
                        register guint16 data;
#ifdef LITTLE
                        data = *((short *) s);
#else
                        data = *((short *) s);
                        data = ((data >> 8) & 0xff) | ((data & 0xff) << 8);
#endif
                        ((char *) o)[0] = ((data >> 8) & 0xf8) | ((data >> 13) & 0x7);
                        ((char *) o)[1] = ((data >> 3) & 0xfc) | ((data >> 9) & 0x3);
                        ((char *) o)[2] = ((data << 3) & 0xf8) | ((data >> 2) & 0x7);
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 16 bits/pixel data
  no alpha
  data in msb format
*/
static void
rgb565msb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

#ifdef LITTLE
        register guint8 *s;     /* need to swap data order */
#else
        register guint32 *s;    /* read 2 pixels at once */
#endif
        register guint16 *o;
        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
#ifdef LITTLE
                s = srow;
#else
                s = (guint32 *) srow;
#endif
                o = (guint16 *) orow;
                for (xx = 1; xx < width; xx += 2) {
                        register guint32 data;
#ifdef LITTLE
                        /* swap endianness first */
                        data = s[0] | s[1] << 8 | s[2] << 16 | s[3] << 24;
                        s += 4;
                        *o++ = (data & 0xf800) >> 8 | (data & 0xe000) >> 13
                                | (data & 0x7e0) << 5 | (data & 0x600) >> 1;
                        *o++ = (data & 0x1f) << 3 | (data & 0x1c) >> 2
                                | (data & 0xf8000000) >> 16 | (data & 0xe0000000) >> 21;
                        *o++ = (data & 0x7e00000) >> 19 | (data & 0x6000000) >> 25
                                | (data & 0x1f0000) >> 5 | (data & 0x1c0000) >> 10;
#else
                        data = *s++;
                        *o++ = (data & 0xf800) | (data & 0xe000) >> 5
                                | (data & 0x7e0) >> 3 | (data & 0x600) >> 9;
                        *o++ = (data & 0x1f) << 11 | (data & 0x1c) << 6
                                | (data & 0xf8000000) >> 24 | (data & 0xe0000000) >> 29;
                        *o++ = (data & 0x7e00000) >> 11 | (data & 0x6000000) >> 17
                                | (data & 0x1f0000) >> 13 | (data & 0x1c0000) >> 18;
#endif
                }
                /* check for last remaining pixel */
                if (width & 1) {
                        register guint16 data;
#ifdef LITTLE
                        data = *((short *) s);
                        data = ((data >> 8) & 0xff) | ((data & 0xff) << 8);
#else
                        data = *((short *) s);
#endif
                        ((char *) o)[0] = ((data >> 8) & 0xf8) | ((data >> 13) & 0x7);
                        ((char *) o)[1] = ((data >> 3) & 0xfc) | ((data >> 9) & 0x3);
                        ((char *) o)[2] = ((data << 3) & 0xf8) | ((data >> 2) & 0x7);
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 16 bits/pixel data
  with alpha
  data in lsb format
*/
static void
rgb565alsb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

#ifdef LITTLE
        register guint16 *s;    /* read 1 pixels at once */
#else
        register guint8 *s;
#endif
        register guint32 *o;

        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
#ifdef LITTLE
                s = (guint16 *) srow;
#else
                s = (guint8 *) srow;
#endif
                o = (guint32 *) orow;
                for (xx = 0; xx < width; xx ++) {
                        register guint32 data;
                        /*  rrrrrggg gggbbbbb -> rrrrrRRR ggggggGG bbbbbBBB aaaaaaaa */
                        /*  little endian: aaaaaaaa bbbbbBBB ggggggGG rrrrrRRR */
#ifdef LITTLE
                        data = *s++;
                        *o++ = (data & 0xf800) >> 8 | (data & 0xe000) >> 13
                                | (data & 0x7e0) << 5 | (data & 0x600) >> 1
                                | (data & 0x1f) << 19 | (data & 0x1c) << 14
                                | 0xff000000;
#else
                        /* swap endianness first */
                        data = s[0] | s[1] << 8;
                        s += 2;
                        *o++ = (data & 0xf800) << 16 | (data & 0xe000) << 11
                                | (data & 0x7e0) << 13 | (data & 0x600) << 7
                                | (data & 0x1f) << 11 | (data & 0x1c) << 6
                                | 0xff;
#endif
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 16 bits/pixel data
  with alpha
  data in msb format
*/
static void
rgb565amsb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

#ifdef LITTLE
        register guint8 *s;
#else
        register guint16 *s;    /* read 1 pixels at once */
#endif
        register guint32 *o;

        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = (guint32 *) orow;
                for (xx = 0; xx < width; xx ++) {
                        register guint32 data;
                        /*  rrrrrggg gggbbbbb -> rrrrrRRR gggggg00 bbbbbBBB aaaaaaaa */
                        /*  little endian: aaaaaaaa bbbbbBBB gggggg00 rrrrrRRR */
#ifdef LITTLE
                        /* swap endianness first */
                        data = s[0] | s[1] << 8;
                        s += 2;
                        *o++ = (data & 0xf800) >> 8 | (data & 0xe000) >> 13
                                | (data & 0x7e0) << 5 | (data & 0x600) >> 1
                                | (data & 0x1f) << 19 | (data & 0x1c) << 14
                                | 0xff000000;
#else
                        data = *s++;
                        *o++ = (data & 0xf800) << 16 | (data & 0xe000) << 11
                                | (data & 0x7e0) << 13 | (data & 0x600) << 7
                                | (data & 0x1f) << 11 | (data & 0x1c) << 6
                                | 0xff;
#endif
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 15 bits/pixel data
  no alpha
  data in lsb format
*/
static void
rgb555lsb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

#ifdef LITTLE
        register guint32 *s;    /* read 2 pixels at once */
#else
        register guint8 *s;     /* read 2 pixels at once */
#endif
        register guint16 *o;
        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
#ifdef LITTLE
                s = (guint32 *) srow;
#else
                s = srow;
#endif
                o = (guint16 *) orow;
                for (xx = 1; xx < width; xx += 2) {
                        register guint32 data;
#ifdef LITTLE
                        data = *s++;
                        *o++ = (data & 0x7c00) >> 7 | (data & 0x7000) >> 12
                                | (data & 0x3e0) << 6 | (data & 0x380) << 1;
                        *o++ = (data & 0x1f) << 3 | (data & 0x1c) >> 2
                                | (data & 0x7c000000) >> 15 | (data & 0x70000000) >> 20;
                        *o++ = (data & 0x3e00000) >> 18 | (data & 0x3800000) >> 23
                                | (data & 0x1f0000) >> 5 | (data & 0x1c0000) >> 10;
#else
                        /* swap endianness first */
                        data = s[0] | s[1] << 8 | s[2] << 16 | s[3] << 24;
                        s += 4;
                        *o++ = (data & 0x7c00) << 1 | (data & 0x7000) >> 4
                                | (data & 0x3e0) >> 2 | (data & 0x380) >> 7;
                        *o++ = (data & 0x1f) << 11 | (data & 0x1c) << 6
                                | (data & 0x7c000000) >> 23 | (data & 0x70000000) >> 28;
                        *o++ = (data & 0x3e00000) >> 10 | (data & 0x3800000) >> 15
                                | (data & 0x1f0000) >> 13 | (data & 0x1c0000) >> 18;
#endif
                }
                /* check for last remaining pixel */
                if (width & 1) {
                        register guint16 data;
#ifdef LITTLE
                        data = *((short *) s);
#else
                        data = *((short *) s);
                        data = ((data >> 8) & 0xff) | ((data & 0xff) << 8);
#endif
                        ((char *) o)[0] = (data & 0x7c00) >> 7 | (data & 0x7000) >> 12;
                        ((char *) o)[1] = (data & 0x3e0) >> 2 | (data & 0x380) >> 7;
                        ((char *) o)[2] = (data & 0x1f) << 3 | (data & 0x1c) >> 2;
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 15 bits/pixel data
  no alpha
  data in msb format
*/
static void
rgb555msb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

#ifdef LITTLE
        register guint8 *s;     /* read 2 pixels at once */
#else
        register guint32 *s;    /* read 2 pixels at once */
#endif
        register guint16 *o;
        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = (guint16 *) orow;
                for (xx = 1; xx < width; xx += 2) {
                        register guint32 data;
#ifdef LITTLE
                        /* swap endianness first */
                        data = s[0] | s[1] << 8 | s[2] << 16 | s[3] << 24;
                        s += 4;
                        *o++ = (data & 0x7c00) >> 7 | (data & 0x7000) >> 12
                                | (data & 0x3e0) << 6 | (data & 0x380) << 1;
                        *o++ = (data & 0x1f) << 3 | (data & 0x1c) >> 2
                                | (data & 0x7c000000) >> 15 | (data & 0x70000000) >> 20;
                        *o++ = (data & 0x3e00000) >> 18 | (data & 0x3800000) >> 23
                                | (data & 0x1f0000) >> 5 | (data & 0x1c0000) >> 10;
#else
                        data = *s++;
                        *o++ = (data & 0x7c00) << 1 | (data & 0x7000) >> 4
                                | (data & 0x3e0) >> 2 | (data & 0x380) >> 7;
                        *o++ = (data & 0x1f) << 11 | (data & 0x1c) << 6
                                | (data & 0x7c000000) >> 23 | (data & 0x70000000) >> 28;
                        *o++ = (data & 0x3e00000) >> 10 | (data & 0x3800000) >> 15
                                | (data & 0x1f0000) >> 13 | (data & 0x1c0000) >> 18;
#endif
                }
                /* check for last remaining pixel */
                if (width & 1) {
                        register guint16 data;
#ifdef LITTLE
                        data = *((short *) s);
                        data = ((data >> 8) & 0xff) | ((data & 0xff) << 8);
#else
                        data = *((short *) s);
#endif
                        ((char *) o)[0] = (data & 0x7c00) >> 7 | (data & 0x7000) >> 12;
                        ((char *) o)[1] = (data & 0x3e0) >> 2 | (data & 0x380) >> 7;
                        ((char *) o)[2] = (data & 0x1f) << 3 | (data & 0x1c) >> 2;
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 15 bits/pixel data
  with alpha
  data in lsb format
*/
static void
rgb555alsb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

#ifdef LITTLE
        register guint16 *s;    /* read 1 pixels at once */
#else
        register guint8 *s;
#endif
        register guint32 *o;

        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
#ifdef LITTLE
                s = (guint16 *) srow;
#else
                s = srow;
#endif
                o = (guint32 *) orow;
                for (xx = 0; xx < width; xx++) {
                        register guint32 data;
                        /*  rrrrrggg gggbbbbb -> rrrrrRRR gggggGGG bbbbbBBB aaaaaaaa */
                        /*  little endian: aaaaaaaa bbbbbBBB gggggGGG rrrrrRRR */
#ifdef LITTLE
                        data = *s++;
                        *o++ = (data & 0x7c00) >> 7 | (data & 0x7000) >> 12
                                | (data & 0x3e0) << 6 | (data & 0x380) << 1
                                | (data & 0x1f) << 19 | (data & 0x1c) << 14
                                | 0xff000000;
#else
                        /* swap endianness first */
                        data = s[0] | s[1] << 8;
                        s += 2;
                        *o++ = (data & 0x7c00) << 17 | (data & 0x7000) << 12
                                | (data & 0x3e0) << 14 | (data & 0x380) << 9
                                | (data & 0x1f) << 11 | (data & 0x1c) << 6
                                | 0xff;
#endif
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  convert 15 bits/pixel data
  with alpha
  data in msb format
*/
static void
rgb555amsb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

#ifdef LITTLE
        register guint16 *s;    /* read 1 pixels at once */
#else
        register guint8 *s;
#endif
        register guint32 *o;

        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
#ifdef LITTLE
                s = (guint16 *) srow;
#else
                s = srow;
#endif
                o = (guint32 *) orow;
                for (xx = 0; xx < width; xx++) {
                        register guint32 data;
                        /*  rrrrrggg gggbbbbb -> rrrrrRRR gggggGGG bbbbbBBB aaaaaaaa */
                        /*  little endian: aaaaaaaa bbbbbBBB gggggGGG rrrrrRRR */
#ifdef LITTLE
                        /* swap endianness first */
                        data = s[0] | s[1] << 8;
                        s += 2;
                        *o++ = (data & 0x7c00) >> 7 | (data & 0x7000) >> 12
                                | (data & 0x3e0) << 6 | (data & 0x380) << 1
                                | (data & 0x1f) << 19 | (data & 0x1c) << 14
                                | 0xff000000;
#else
                        data = *s++;
                        *o++ = (data & 0x7c00) << 17 | (data & 0x7000) << 12
                                | (data & 0x3e0) << 14 | (data & 0x380) << 9
                                | (data & 0x1f) << 11 | (data & 0x1c) << 6
                                | 0xff;
#endif
                }
                srow += bpl;
                orow += rowstride;
        }
}


static void
rgb888alsb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

        guint8 *s;      /* for byte order swapping */
        guint8 *o;
        guint8 *srow = image->mem, *orow = pixels;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        d (printf ("32 bits/pixel with alpha\n"));

        /* lsb data */
        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = orow;
                for (xx = 0; xx < width; xx++) {
                        *o++ = s[2];
                        *o++ = s[1];
                        *o++ = s[0];
                        *o++ = 0xff;
                        s += 4;
                }
                srow += bpl;
                orow += rowstride;
        }
}

static void
rgb888lsb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

        guint8 *srow = image->mem, *orow = pixels;
        guint8 *o, *s;

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        d (printf ("32 bit, lsb, no alpha\n"));

        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = orow;
                for (xx = 0; xx < width; xx++) {
                        *o++ = s[2];
                        *o++ = s[1];
                        *o++ = s[0];
                        s += 4;
                }
                srow += bpl;
                orow += rowstride;
        }
}

static void
rgb888amsb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

        guint8 *srow = image->mem, *orow = pixels;
#ifdef LITTLE
        guint32 *o;
        guint32 *s;
#else
        guint8 *s;      /* for byte order swapping */
        guint8 *o;
#endif

        d (printf ("32 bit, msb, with alpha\n"));

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        /* msb data */
        for (yy = 0; yy < height; yy++) {
#ifdef LITTLE
                s = (guint32 *) srow;
                o = (guint32 *) orow;
#else
                s = srow;
                o = orow;
#endif
                for (xx = 0; xx < width; xx++) {
#ifdef LITTLE
                        *o++ = s[1];
                        *o++ = s[2];
                        *o++ = s[3];
                        *o++ = 0xff;
                        s += 4;
#else
                        *o++ = (*s << 8) | 0xff; /* untested */
                        s++;
#endif
                }
                srow += bpl;
                orow += rowstride;
        }
}

static void
rgb888msb (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *colormap)
{
        int xx, yy;
        int width, height;
        int bpl;

        guint8 *srow = image->mem, *orow = pixels;
        guint8 *s;
        guint8 *o;

        d (printf ("32 bit, msb, no alpha\n"));

        width = image->width;
        height = image->height;
        bpl = image->bpl;

        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = orow;
                for (xx = 0; xx < width; xx++) {
                        *o++ = s[1];
                        *o++ = s[2];
                        *o++ = s[3];
                        s += 4;
                }
                srow += bpl;
                orow += rowstride;
        }
}

/*
  This should work correctly with any display/any endianness, but will probably
  run quite slow
*/
static void
convert_real_slow (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *cmap, int alpha)
{
        int xx, yy;
        int width, height;
        int bpl;
        guint8 *srow = image->mem, *orow = pixels;
        guint8 *s;
        guint8 *o;
        guint32 pixel;
        GdkVisual *v;
        guint8 component;
        int i;

        width = image->width;
        height = image->height;
        bpl = image->bpl;
        v = gdk_colormap_get_visual(cmap);

        d(printf("rgb  mask/shift/prec = %x:%x:%x %d:%d:%d  %d:%d:%d\n",
                 v->red_mask, v->green_mask, v->blue_mask,
                 v->red_shift, v->green_shift, v->blue_shift,
                 v->red_prec, v->green_prec, v->blue_prec));

        for (yy = 0; yy < height; yy++) {
                s = srow;
                o = orow;
                for (xx = 0; xx < width; xx++) {
                        pixel = gdk_image_get_pixel(image, xx, yy);
                        switch (v->type) {
                                /* I assume this is right for static & greyscale's too? */
                        case GDK_VISUAL_STATIC_GRAY:
                        case GDK_VISUAL_GRAYSCALE:
                        case GDK_VISUAL_STATIC_COLOR:
                        case GDK_VISUAL_PSEUDO_COLOR:
                                *o++ = cmap->colors[pixel].red;
                                *o++ = cmap->colors[pixel].green;
                                *o++ = cmap->colors[pixel].blue;
                                break;
                        case GDK_VISUAL_TRUE_COLOR:
                                /* This is odd because it must sometimes shift left (otherwise
                                   I'd just shift >> (*_shift - 8 + *_prec + <0-7>). This logic
                                   should work for all bit sizes/shifts/etc. */
                                component = 0;
                                for (i = 24; i < 32; i += v->red_prec)
                                        component |= ((pixel & v->red_mask) << (32 - v->red_shift - v->red_prec)) >> i;
                                *o++ = component;
                                component = 0;
                                for (i = 24; i < 32; i += v->green_prec)
                                        component |= ((pixel & v->green_mask) << (32 - v->green_shift - v->green_prec)) >> i;
                                *o++ = component;
                                component = 0;
                                for (i = 24; i < 32; i += v->blue_prec)
                                        component |= ((pixel & v->blue_mask) << (32 - v->blue_shift - v->blue_prec)) >> i;
                                *o++ = component;
                                break;
                        case GDK_VISUAL_DIRECT_COLOR:
                                *o++ = cmap->colors[((pixel & v->red_mask) << (32 - v->red_shift - v->red_prec)) >> 24].red;
                                *o++ = cmap->colors[((pixel & v->green_mask) << (32 - v->green_shift - v->green_prec)) >> 24].green;
                                *o++ = cmap->colors[((pixel & v->blue_mask) << (32 - v->blue_shift - v->blue_prec)) >> 24].blue;
                                break;
                        }
                        if (alpha)
                                *o++ = 0xff;
                }
                srow += bpl;
                orow += rowstride;
        }
}

typedef void (* cfunc) (GdkImage *image, guchar *pixels, int rowstride, GdkColormap *cmap);

static cfunc convert_map[] = {
        rgb1,rgb1,rgb1a,rgb1a,
        rgb8,rgb8,rgb8a,rgb8a,
        rgb555lsb,rgb555msb,rgb555alsb,rgb555amsb,
        rgb565lsb,rgb565msb,rgb565alsb,rgb565amsb,
        rgb888lsb,rgb888msb,rgb888alsb,rgb888amsb
};

/*
  perform actual conversion

  If we can, try and use the optimised code versions, but as a default
  fallback, and always for direct colour, use the generic/slow but complete
  conversion function.
*/
static void
rgbconvert (GdkImage *image, guchar *pixels, int rowstride, int alpha, GdkColormap *cmap)
{
        int index = (image->byte_order == GDK_MSB_FIRST) | (alpha != 0) << 1;
        int bank=5;             /* default fallback converter */
        GdkVisual *v = gdk_colormap_get_visual(cmap);

        d(printf("masks = %x:%x:%x\n", v->red_mask, v->green_mask, v->blue_mask));
        d(printf("image depth = %d, bpp = %d\n", image->depth, image->bpp));

        switch (v->type) {
                                /* I assume this is right for static & greyscale's too? */
        case GDK_VISUAL_STATIC_GRAY:
        case GDK_VISUAL_GRAYSCALE:
        case GDK_VISUAL_STATIC_COLOR:
        case GDK_VISUAL_PSEUDO_COLOR:
                switch (image->bpp) {
                case 1:
                        bank = 0;
                        break;
                case 8:
                        bank = 1;
                        break;
                }
                break;
        case GDK_VISUAL_TRUE_COLOR:
                switch (image->depth) {
                case 15:
                        if (v->red_mask == 0x7c00 && v->green_mask == 0x3e0 && v->blue_mask == 0x1f
                            && image->bpp == 16)
                                bank = 2;
                        break;
                case 16:
                        if (v->red_mask == 0xf800 && v->green_mask == 0x7e0 && v->blue_mask == 0x1f
                            && image->bpp == 16)
                                bank = 3;
                        break;
                case 24:
                case 32:
                        if (v->red_mask == 0xff0000 && v->green_mask == 0xff00 && v->blue_mask == 0xff
                            && image->bpp == 32)
                                bank = 4;
                        break;
                }
                break;
        case GDK_VISUAL_DIRECT_COLOR:
                /* always use the slow version */
                break;
        }

        d(printf("converting using conversion function in bank %d\n", bank));

        if (bank==5) {
                convert_real_slow(image, pixels, rowstride, cmap, alpha);
        } else {
                index |= bank << 2;
                (* convert_map[index]) (image, pixels, rowstride, cmap);
        }
}


/* Exported functions */

/**
 * gdk_pixbuf_get_from_drawable:
 * @dest: Destination pixbuf, or NULL if a new pixbuf should be created.
 * @src: Source drawable.
 * @cmap: A colormap if @src is a pixmap.  If it is a window, this argument will
 * be ignored.
 * @src_x: Source X coordinate within drawable.
 * @src_y: Source Y coordinate within drawable.
 * @dest_x: Destination X coordinate in pixbuf, or 0 if @dest is NULL.
 * @dest_y: Destination Y coordinate in pixbuf, or 0 if @dest is NULL.
 * @width: Width in pixels of region to get.
 * @height: Height in pixels of region to get.
 *
 * Transfers image data from a Gdk drawable and converts it to an RGB(A)
 * representation inside a GdkPixbuf.
 *
 * If the drawable @src is a pixmap, then a suitable colormap must be specified,
 * since pixmaps are just blocks of pixel data without an associated colormap.
 * If the drawable is a window, the @cmap argument will be ignored and the
 * window's own colormap will be used instead.
 *
 * If the specified destination pixbuf @dest is #NULL, then this function will
 * create an RGB pixbuf with 8 bits per channel and no alpha, with the same size
 * specified by the @width and @height arguments.  In this case, the @dest_x and
 * @dest_y arguments must be specified as 0, otherwise the function will return
 * #NULL.  If the specified destination pixbuf is not NULL and it contains alpha
 * information, then the filled pixels will be set to full opacity.
 *
 * If the specified drawable is a pixmap, then the requested source rectangle
 * must be completely contained within the pixmap, otherwise the function will
 * return #NULL.
 *
 * If the specified drawable is a window, then it must be viewable, i.e. all of
 * its ancestors up to the root window must be mapped.  Also, the specified
 * source rectangle must be completely contained within the window and within
 * the screen.  If regions of the window are obscured by noninferior windows, the
 * contents of those regions are undefined.  The contents of regions obscured by
 * inferior windows of a different depth than that of the source window will also
 * be undefined.
 *
 * Return value: The same pixbuf as @dest if it was non-NULL, or a newly-created
 * pixbuf with a reference count of 1 if no destination pixbuf was specified; in
 * the latter case, NULL will be returned if not enough memory could be
 * allocated for the pixbuf to be created.
 **/
GdkPixbuf * NAUTILUS_BUG_5712_PR3_WORKAROUND__gdk_pixbuf_get_from_drawable (GdkPixbuf *dest,
                                                                            GdkDrawable *src, GdkColormap *cmap,
                                                                            int src_x, int src_y,
                                                                            int dest_x, int dest_y,
                                                                            int width, int height);


GdkImage* NAUTILUS_BUG_5712_PR3_WORKAROUND__gdk_image_get (GdkWindow *window,
                                                           gint       x,
                                                           gint       y,
                                                           gint       width,
                                                           gint       height);

GdkPixbuf *
NAUTILUS_BUG_5712_PR3_WORKAROUND__gdk_pixbuf_get_from_drawable (GdkPixbuf *dest,
                              GdkDrawable *src, GdkColormap *cmap,
                              int src_x, int src_y,
                              int dest_x, int dest_y,
                              int width, int height)
{
        GdkWindowType window_type;
        int src_width, src_height;
        GdkImage *image;
        int rowstride, bpp, alpha;

        /* General sanity checks */

        g_return_val_if_fail (src != NULL, NULL);

        window_type = gdk_window_get_type (src);

        if (window_type == GDK_WINDOW_PIXMAP)
                g_return_val_if_fail (cmap != NULL, NULL);
        else
                /* FIXME: this is not perfect, since is_viewable() only tests
                 * recursively up the Gdk parent window tree, but stops at
                 * foreign windows or Gdk toplevels.  I.e. if a window manager
                 * unmapped one of its own windows, this won't work.
                 */
                g_return_val_if_fail (gdk_window_is_viewable (src), NULL);

        if (!dest)
                g_return_val_if_fail (dest_x == 0 && dest_y == 0, NULL);
        else {
                g_return_val_if_fail (dest->colorspace == GDK_COLORSPACE_RGB, NULL);
                g_return_val_if_fail (dest->n_channels == 3 || dest->n_channels == 4, NULL);
                g_return_val_if_fail (dest->bits_per_sample == 8, NULL);
        }

        /* Coordinate sanity checks */

        gdk_window_get_size (src, &src_width, &src_height);

        g_return_val_if_fail (src_x >= 0 && src_y >= 0, NULL);
        g_return_val_if_fail (src_x + width <= src_width && src_y + height <= src_height, NULL);

        if (dest) {
                g_return_val_if_fail (dest_x >= 0 && dest_y >= 0, NULL);
                g_return_val_if_fail (dest_x + width <= dest->width, NULL);
                g_return_val_if_fail (dest_y + height <= dest->height, NULL);
        }

        if (window_type != GDK_WINDOW_PIXMAP) {
                int ret;
                int src_xorigin, src_yorigin;
                int screen_width, screen_height;
                int screen_srcx, screen_srcy;

                ret = gdk_window_get_origin (src, &src_xorigin, &src_yorigin);
                g_return_val_if_fail (ret != FALSE, NULL);

                screen_width = gdk_screen_width ();
                screen_height = gdk_screen_height ();

                screen_srcx = src_xorigin + src_x;
                screen_srcy = src_yorigin + src_y;

                g_return_val_if_fail (screen_srcx >= 0 && screen_srcy >= 0, NULL);
                g_return_val_if_fail (screen_srcx + width <= screen_width, NULL);
                g_return_val_if_fail (screen_srcy + height <= screen_height, NULL);
        }

        /* Get Image in ZPixmap format (packed bits). */
        image = NAUTILUS_BUG_5712_PR3_WORKAROUND__gdk_image_get (src, src_x, src_y, width, height);
        if (!image)
                return NULL;

        /* Create the pixbuf if needed */
        if (!dest) {
                dest = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, width, height);
                if (!dest) {
                        gdk_image_destroy(image);
                        return NULL;
                }
        }

        /* Get the colormap if needed */
        if (window_type != GDK_WINDOW_PIXMAP)
                cmap = gdk_window_get_colormap (src);

        alpha = dest->has_alpha;
        rowstride = dest->rowstride;
        bpp = alpha ? 4 : 3;

        /* we offset into the image data based on the position we are retrieving from */
        rgbconvert (image, dest->pixels +
                    (dest_y * rowstride) + (dest_x * bpp),
                    rowstride,
                    alpha,
                    cmap);

        gdk_image_destroy(image);

        return dest;
}