xputimage.c

早期freebsd实现

/* $XConsortium: XPutImage.c,v 11.60 91/06/07 16:33:38 rws Exp $ */
/* Copyright    Massachusetts Institute of Technology    1986	*/

/*
Permission to use, copy, modify, distribute, and sell this software and its
documentation for any purpose is hereby granted without fee, provided that
the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation, and that the name of M.I.T. not be used in advertising or
publicity pertaining to distribution of the software without specific,
written prior permission.  M.I.T. makes no representations about the
suitability of this software for any purpose.  It is provided "as is"
without express or implied warranty.
*/

#include <X11/Xlibint.h>
#include <stdio.h>

#if __STDC__
#define Const const
#else
#define Const /**/
#endif

/* assumes pad is a power of 2 */
#define ROUNDUP(nbytes, pad) (((nbytes) + ((pad) - 1)) & ~(long)((pad) - 1))

static unsigned char Const _reverse_byte[0x100] = {
	0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
	0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
	0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
	0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
	0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
	0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
	0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
	0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
	0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
	0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
	0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
	0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
	0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
	0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
	0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
	0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
	0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
	0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
	0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
	0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
	0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
	0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
	0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
	0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
	0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
	0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
	0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
	0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
	0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
	0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
	0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
	0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff
};

static unsigned char Const _reverse_nibs[0x100] = {
	0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70,
	0x80, 0x90, 0xa0, 0xb0, 0xc0, 0xd0, 0xe0, 0xf0,
	0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71,
	0x81, 0x91, 0xa1, 0xb1, 0xc1, 0xd1, 0xe1, 0xf1,
	0x02, 0x12, 0x22, 0x32, 0x42, 0x52, 0x62, 0x72,
	0x82, 0x92, 0xa2, 0xb2, 0xc2, 0xd2, 0xe2, 0xf2,
	0x03, 0x13, 0x23, 0x33, 0x43, 0x53, 0x63, 0x73,
	0x83, 0x93, 0xa3, 0xb3, 0xc3, 0xd3, 0xe3, 0xf3,
	0x04, 0x14, 0x24, 0x34, 0x44, 0x54, 0x64, 0x74,
	0x84, 0x94, 0xa4, 0xb4, 0xc4, 0xd4, 0xe4, 0xf4,
	0x05, 0x15, 0x25, 0x35, 0x45, 0x55, 0x65, 0x75,
	0x85, 0x95, 0xa5, 0xb5, 0xc5, 0xd5, 0xe5, 0xf5,
	0x06, 0x16, 0x26, 0x36, 0x46, 0x56, 0x66, 0x76,
	0x86, 0x96, 0xa6, 0xb6, 0xc6, 0xd6, 0xe6, 0xf6,
	0x07, 0x17, 0x27, 0x37, 0x47, 0x57, 0x67, 0x77,
	0x87, 0x97, 0xa7, 0xb7, 0xc7, 0xd7, 0xe7, 0xf7,
	0x08, 0x18, 0x28, 0x38, 0x48, 0x58, 0x68, 0x78,
	0x88, 0x98, 0xa8, 0xb8, 0xc8, 0xd8, 0xe8, 0xf8,
	0x09, 0x19, 0x29, 0x39, 0x49, 0x59, 0x69, 0x79,
	0x89, 0x99, 0xa9, 0xb9, 0xc9, 0xd9, 0xe9, 0xf9,
	0x0a, 0x1a, 0x2a, 0x3a, 0x4a, 0x5a, 0x6a, 0x7a,
	0x8a, 0x9a, 0xaa, 0xba, 0xca, 0xda, 0xea, 0xfa,
	0x0b, 0x1b, 0x2b, 0x3b, 0x4b, 0x5b, 0x6b, 0x7b,
	0x8b, 0x9b, 0xab, 0xbb, 0xcb, 0xdb, 0xeb, 0xfb,
	0x0c, 0x1c, 0x2c, 0x3c, 0x4c, 0x5c, 0x6c, 0x7c,
	0x8c, 0x9c, 0xac, 0xbc, 0xcc, 0xdc, 0xec, 0xfc,
	0x0d, 0x1d, 0x2d, 0x3d, 0x4d, 0x5d, 0x6d, 0x7d,
	0x8d, 0x9d, 0xad, 0xbd, 0xcd, 0xdd, 0xed, 0xfd,
	0x0e, 0x1e, 0x2e, 0x3e, 0x4e, 0x5e, 0x6e, 0x7e,
	0x8e, 0x9e, 0xae, 0xbe, 0xce, 0xde, 0xee, 0xfe,
	0x0f, 0x1f, 0x2f, 0x3f, 0x4f, 0x5f, 0x6f, 0x7f,
	0x8f, 0x9f, 0xaf, 0xbf, 0xcf, 0xdf, 0xef, 0xff
};


_XReverse_Bytes (bpt, nb)
    register unsigned char *bpt;
    register int nb;
{
    do {
	*bpt = _reverse_byte[*bpt];
	bpt++;
    } while (--nb > 0);
    return;
}


/* XXX the following functions are declared int instead of void because various
 * compilers and lints complain about later intialization of SwapFunc and/or
 * (swapfunc == NoSwap) when void is used.
 */

/*ARGSUSED*/
static int
NoSwap (src, dest, srclen, srcinc, destinc, height, half_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
    int half_order;
{
    long h = height;

    if (srcinc == destinc)
	bcopy((char *)src, (char *)dest, (int)(srcinc * (h - 1) + srclen));
    else
	for (; --h >= 0; src += srcinc, dest += destinc)
	    bcopy((char *)src, (char *)dest, (int)srclen);
}

static int
SwapTwoBytes (src, dest, srclen, srcinc, destinc, height, half_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
    int half_order;
{
    long length = ROUNDUP(srclen, 2);
    register long h, n;

    srcinc -= length;
    destinc -= length;
    for (h = height; --h >= 0; src += srcinc, dest += destinc) {
	if ((h == 0) && (srclen != length)) {
	    length -= 2;
	    if (half_order == MSBFirst)
		*(dest + length) = *(src + length + 1);
	    else
		*(dest + length + 1) = *(src + length);
	}
	for (n = length; n > 0; n -= 2, src += 2) {
	    *dest++ = *(src + 1);
	    *dest++ = *src;
	}
    }
}

static int
SwapThreeBytes (src, dest, srclen, srcinc, destinc, height, byte_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
    int byte_order;
{
    long length = ((srclen + 2) / 3) * 3;
    register long h, n;

    srcinc -= length;
    destinc -= length;
    for (h = height; --h >= 0; src += srcinc, dest += destinc) {
	if ((h == 0) && (srclen != length)) {
	    length -= 3;
	    if ((srclen - length) == 2)
		*(dest + length + 1) = *(src + length + 1);
	    if (byte_order == MSBFirst)
		*(dest + length) = *(src + length + 2);
	    else
		*(dest + length + 2) = *(src + length);
	}
	for (n = length; n > 0; n -= 3, src += 3) {
	    *dest++ = *(src + 2);
	    *dest++ = *(src + 1);
	    *dest++ = *src;
	}
    }
}

static int
SwapFourBytes (src, dest, srclen, srcinc, destinc, height, half_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
    int half_order;
{
    long length = ROUNDUP(srclen, 4);
    register long h, n;

    srcinc -= length;
    destinc -= length;
    for (h = height; --h >= 0; src += srcinc, dest += destinc) {
	if ((h == 0) && (srclen != length)) {
	    length -= 4;
	    if (half_order == MSBFirst)
		*(dest + length) = *(src + length + 3);
	    if (((half_order == LSBFirst) && ((srclen - length) == 3)) ||
		((half_order == MSBFirst) && (srclen & 2)))
		*(dest + length + 1) = *(src + length + 2);
	    if (((half_order == MSBFirst) && ((srclen - length) == 3)) ||
		((half_order == LSBFirst) && (srclen & 2)))
		*(dest + length + 2) = *(src + length + 1);
	    if (half_order == LSBFirst)
		*(dest + length + 3) = *(src + length);
	}
	for (n = length; n > 0; n -= 4, src += 4) {
	    *dest++ = *(src + 3);
	    *dest++ = *(src + 2);
	    *dest++ = *(src + 1);
	    *dest++ = *src;
	}
    }
}

static int
SwapWords (src, dest, srclen, srcinc, destinc, height, half_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
    int half_order;
{
    long length = ROUNDUP(srclen, 4);
    register long h, n;

    srcinc -= length;
    destinc -= length;
    for (h = height; --h >= 0; src += srcinc, dest += destinc) {
	if ((h == 0) && (srclen != length)) {
	    length -= 4;
	    if (half_order == MSBFirst)
		*(dest + length + 1) = *(src + length + 3);
	    if (((half_order == LSBFirst) && ((srclen - length) == 3)) ||
		((half_order == MSBFirst) && (srclen & 2)))
		*(dest + length) = *(src + length + 2);
	    if (((half_order == MSBFirst) && ((srclen - length) == 3)) ||
		((half_order == LSBFirst) && (srclen & 2)))
		*(dest + length + 3) = *(src + length + 1);
	    if (half_order == LSBFirst)
		*(dest + length + 2) = *(src + length);
	}
	for (n = length; n > 0; n -= 4, src += 2) {
	    *dest++ = *(src + 2);
	    *dest++ = *(src + 3);
	    *dest++ = *src++;
	    *dest++ = *src++;
	}
    }
}

static int
SwapNibbles (src, dest, srclen, srcinc, destinc, height)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
{
    register long h, n;
    register Const unsigned char *rev = _reverse_nibs;

    srcinc -= srclen;
    destinc -= srclen;
    for (h = height; --h >= 0; src += srcinc, dest += destinc)
	for (n = srclen; --n >= 0; )
	    *dest++ = rev[*src++];
}

static int
ShiftNibblesLeft (src, dest, srclen, srcinc, destinc, height, nibble_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
    int nibble_order;
{
    register long h, n;
    register unsigned char c1, c2;

    srcinc -= srclen;
    destinc -= srclen;
    if (nibble_order == MSBFirst) {
	for (h = height; --h >= 0; src += srcinc, dest += destinc)
	    for (n = srclen; --n >= 0; ) {
		c1 = *src++;
		c2 = *src;
		*dest++ = ((c1 & 0x0f) << 4) | ((c2 & (unsigned)0xf0) >> 4);
	    }
    } else {
	for (h = height; --h >= 0; src += srcinc, dest += destinc)
	    for (n = srclen; --n >= 0; ) {
		c1 = *src++;
		c2 = *src;
		*dest++ = ((c2 & 0x0f) << 4) | ((c1 & (unsigned)0xf0) >> 4);
	    }
    }
}

/*ARGSUSED*/
static int
SwapBits (src, dest, srclen, srcinc, destinc, height, half_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
    int half_order;
{
    register long h, n;
    register Const unsigned char *rev = _reverse_byte;

    srcinc -= srclen;
    destinc -= srclen;
    for (h = height; --h >= 0; src += srcinc, dest += destinc)
	for (n = srclen; --n >= 0; )
	    *dest++ = rev[*src++];
}

static int
SwapBitsAndTwoBytes (src, dest, srclen, srcinc, destinc, height, half_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
{
    long length = ROUNDUP(srclen, 2);
    register long h, n;
    register Const unsigned char *rev = _reverse_byte;

    srcinc -= length;
    destinc -= length;
    for (h = height; --h >= 0; src += srcinc, dest += destinc) {
	if ((h == 0) && (srclen != length)) {
	    length -= 2;
	    if (half_order == MSBFirst)
		*(dest + length) = rev[*(src + length + 1)];
	    else
		*(dest + length + 1) = rev[*(src + length)];
	}
	for (n = length; n > 0; n -= 2, src += 2) {
	    *dest++ = rev[*(src + 1)];
	    *dest++ = rev[*src];
	}
    }
}

static int
SwapBitsAndFourBytes (src, dest, srclen, srcinc, destinc, height, half_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
    int half_order;
{
    long length = ROUNDUP(srclen, 4);
    register long h, n;
    register Const unsigned char *rev = _reverse_byte;

    srcinc -= length;
    destinc -= length;
    for (h = height; --h >= 0; src += srcinc, dest += destinc) {
	if ((h == 0) && (srclen != length)) {
	    length -= 4;
	    if (half_order == MSBFirst)
		*(dest + length) = rev[*(src + length + 3)];
	    if (((half_order == LSBFirst) && ((srclen - length) == 3)) ||
		((half_order == MSBFirst) && (srclen & 2)))
		*(dest + length + 1) = rev[*(src + length + 2)];
	    if (((half_order == MSBFirst) && ((srclen - length) == 3)) ||
		((half_order == LSBFirst) && (srclen & 2)))
		*(dest + length + 2) = rev[*(src + length + 1)];
	    if (half_order == LSBFirst)
		*(dest + length + 3) = rev[*(src + length)];
	}
	for (n = length; n > 0; n -= 4, src += 4) {
	    *dest++ = rev[*(src + 3)];
	    *dest++ = rev[*(src + 2)];
	    *dest++ = rev[*(src + 1)];
	    *dest++ = rev[*src];
	}
    }
}

static int
SwapBitsAndWords (src, dest, srclen, srcinc, destinc, height, half_order)
    register unsigned char *src, *dest;
    long srclen, srcinc, destinc;
    unsigned int height;
    int half_order;
{
    long length = ROUNDUP(srclen, 4);
    register long h, n;
    register Const unsigned char *rev = _reverse_byte;

    srcinc -= length;
    destinc -= length;
    for (h = height; --h >= 0; src += srcinc, dest += destinc) {
	if ((h == 0) && (srclen != length)) {
	    length -= 4;
	    if (half_order == MSBFirst)
		*(dest + length + 1) = rev[*(src + length + 3)];
	    if (((half_order == LSBFirst) && ((srclen - length) == 3)) ||
		((half_order == MSBFirst) && (srclen & 2)))
		*(dest + length) = rev[*(src + length + 2)];
	    if (((half_order == MSBFirst) && ((srclen - length) == 3)) ||
		((half_order == LSBFirst) && (srclen & 2)))
		*(dest + length + 3) = rev[*(src + length + 1)];
	    if (half_order == LSBFirst)
		*(dest + length + 2) = rev[*(src + length)];
	}
	for (n = length; n > 0; n -= 4, src += 2) {
	    *dest++ = rev[*(src + 2)];
	    *dest++ = rev[*(src + 3)];
	    *dest++ = rev[*src++];
	    *dest++ = rev[*src++];
	}
    }
}

/*

The following table gives the bit ordering within bytes (when accessed
sequentially) for a scanline containing 32 bits, with bits numbered 0 to
31, where bit 0 should be leftmost on the display.  For a given byte
labelled A-B, A is for the most significant bit of the byte, and B is
for the least significant bit.

legend:
	1   scanline-unit = 8
	2   scanline-unit = 16
	4   scanline-unit = 32
	M   byte-order = MostSignificant
	L   byte-order = LeastSignificant
	m   bit-order = MostSignificant
	l   bit-order = LeastSignificant


format	ordering

1Mm	00-07 08-15 16-23 24-31
2Mm	00-07 08-15 16-23 24-31
4Mm	00-07 08-15 16-23 24-31
1Ml	07-00 15-08 23-16 31-24
2Ml	15-08 07-00 31-24 23-16
4Ml	31-24 23-16 15-08 07-00
1Lm	00-07 08-15 16-23 24-31
2Lm	08-15 00-07 24-31 16-23
4Lm	24-31 16-23 08-15 00-07
1Ll	07-00 15-08 23-16 31-24
2Ll	07-00 15-08 23-16 31-24
4Ll	07-00 15-08 23-16 31-24


The following table gives the required conversion between any two
formats.  It is based strictly on the table above.  If you believe one,
you should believe the other.

legend:
	n   no changes
	s   reverse 8-bit units within 16-bit units
	l   reverse 8-bit units within 32-bit units
	w   reverse 16-bit units within 32-bit units
	R   reverse bits within 8-bit units
	S   s+R
	L   l+R
	W   w+R

*/

static int (* Const (SwapFunction[12][12]))() = {
#define n NoSwap,
#define s SwapTwoBytes,
#define l SwapFourBytes,
#define w SwapWords,
#define R SwapBits,
#define S SwapBitsAndTwoBytes,
#define L SwapBitsAndFourBytes,
#define W SwapBitsAndWords,

/*         1Mm 2Mm 4Mm 1Ml 2Ml 4Ml 1Lm 2Lm 4Lm 1Ll 2Ll 4Ll   */
/* 1Mm */ { n   n   n   R   S   L   n   s   l   R   R   R },
/* 2Mm */ { n   n   n   R   S   L   n   s   l   R   R   R },
/* 4Mm */ { n   n   n   R   S   L   n   s   l   R   R   R },
/* 1Ml */ { R   R   R   n   s   l   R   S   L   n   n   n },
/* 2Ml */ { S   S   S   s   n   w   S   R   W   s   s   s },
/* 4Ml */ { L   L   L   l   w   n   L   W   R   l   l   l },
/* 1Lm */ { n   n   n   R   S   L   n   s   l   R   R   R },