libtdevnc/tabletranstemplate.c

/*
 * tabletranstemplate.c - template for translation using lookup tables.
 *
 * This file shouldn't be compiled.  It is included multiple times by
 * translate.c, each time with different definitions of the macros IN and OUT.
 *
 * For each pair of values IN and OUT, this file defines two functions for
 * translating a given rectangle of pixel data.  One uses a single lookup
 * table, and the other uses three separate lookup tables for the red, green
 * and blue values.
 *
 * I know this code isn't nice to read because of all the macros, but
 * efficiency is important here.
 */

/*
 *  OSXvnc Copyright (C) 2001 Dan McGuirk <mcguirk@incompleteness.net>.
 *  Original Xvnc code Copyright (C) 1999 AT&T Laboratories Cambridge.  
 *  All Rights Reserved.
 *
 *  This is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This software 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this software; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
 *  USA.
 */

#if !defined(IN) || !defined(OUT)
#error "This file shouldn't be compiled."
#error "It is included as part of translate.c"
#endif

#define IN_T CONCAT3E(uint,IN,_t)
#define OUT_T CONCAT3E(uint,OUT,_t)
#define rfbTranslateWithSingleTableINtoOUT \
                                CONCAT4E(rfbTranslateWithSingleTable,IN,to,OUT)
#define rfbTranslateWithRGBTablesINtoOUT \
                                CONCAT4E(rfbTranslateWithRGBTables,IN,to,OUT)

/*
 * rfbTranslateWithSingleTableINtoOUT translates a rectangle of pixel data
 * using a single lookup table.
 */

static void
rfbTranslateWithSingleTableINtoOUT (char *table, rfbPixelFormat *in,
                                    rfbPixelFormat *out,
                                    char *iptr, char *optr,
                                    int bytesBetweenInputLines,
                                    int width, int height)
{
    IN_T *ip = (IN_T *)iptr;
    OUT_T *op = (OUT_T *)optr;
    int ipextra = bytesBetweenInputLines / sizeof(IN_T) - width;
    OUT_T *opLineEnd;
    OUT_T *t = (OUT_T *)table;

    while (height > 0) {
        opLineEnd = op + width;

        while (op < opLineEnd) {
            *(op++) = t[*(ip++)];
        }

        ip += ipextra;
        height--;
    }
}


/*
 * rfbTranslateWithRGBTablesINtoOUT translates a rectangle of pixel data
 * using three separate lookup tables for the red, green and blue values.
 */

static void
rfbTranslateWithRGBTablesINtoOUT (char *table, rfbPixelFormat *in,
                                  rfbPixelFormat *out,
                                  char *iptr, char *optr,
                                  int bytesBetweenInputLines,
                                  int width, int height)
{
    IN_T *ip = (IN_T *)iptr;
    OUT_T *op = (OUT_T *)optr;
    int ipextra = bytesBetweenInputLines / sizeof(IN_T) - width;
    OUT_T *opLineEnd;
    OUT_T *redTable = (OUT_T *)table;
    OUT_T *greenTable = redTable + in->redMax + 1;
    OUT_T *blueTable = greenTable + in->greenMax + 1;

    while (height > 0) {
        opLineEnd = &op[width];

        while (op < opLineEnd) {
            *(op++) = (redTable[(*ip >> in->redShift) & in->redMax] |
                       greenTable[(*ip >> in->greenShift) & in->greenMax] |
                       blueTable[(*ip >> in->blueShift) & in->blueMax]);
            ip++;
        }
        ip += ipextra;
        height--;
    }
}

#undef IN_T
#undef OUT_T
#undef rfbTranslateWithSingleTableINtoOUT
#undef rfbTranslateWithRGBTablesINtoOUT