/apps/desktop/libvncserver/tableinittctemplate.c

  1/*
  2 * tableinittctemplate.c - template for initialising lookup tables for
  3 * truecolour to truecolour translation.
  4 *
  5 * This file shouldn't be compiled.  It is included multiple times by
  6 * translate.c, each time with a different definition of the macro OUT.
  7 * For each value of OUT, this file defines two functions for initialising
  8 * lookup tables.  One is for truecolour translation using a single lookup
  9 * table, the other is for truecolour translation using three separate
 10 * lookup tables for the red, green and blue values.
 11 *
 12 * I know this code isn't nice to read because of all the macros, but
 13 * efficiency is important here.
 14 */
 15
 16/*
 17 *  OSXvnc Copyright (C) 2001 Dan McGuirk <mcguirk@incompleteness.net>.
 18 *  Original Xvnc code Copyright (C) 1999 AT&T Laboratories Cambridge.  
 19 *  All Rights Reserved.
 20 *
 21 *  This is free software; you can redistribute it and/or modify
 22 *  it under the terms of the GNU General Public License as published by
 23 *  the Free Software Foundation; either version 2 of the License, or
 24 *  (at your option) any later version.
 25 *
 26 *  This software is distributed in the hope that it will be useful,
 27 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 28 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 29 *  GNU General Public License for more details.
 30 *
 31 *  You should have received a copy of the GNU General Public License
 32 *  along with this software; if not, write to the Free Software
 33 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
 34 *  USA.
 35 */
 36
 37#if !defined(OUT)
 38#error "This file shouldn't be compiled."
 39#error "It is included as part of translate.c"
 40#endif
 41
 42#define OUT_T CONCAT3E(uint,OUT,_t)
 43#define SwapOUT(x) CONCAT2E(Swap,OUT(x))
 44#define rfbInitTrueColourSingleTableOUT \
 45                                CONCAT2E(rfbInitTrueColourSingleTable,OUT)
 46#define rfbInitTrueColourRGBTablesOUT CONCAT2E(rfbInitTrueColourRGBTables,OUT)
 47#define rfbInitOneRGBTableOUT CONCAT2E(rfbInitOneRGBTable,OUT)
 48
 49static void
 50rfbInitOneRGBTableOUT (OUT_T *table, int inMax, int outMax, int outShift,
 51                       int swap);
 52
 53
 54/*
 55 * rfbInitTrueColourSingleTable sets up a single lookup table for truecolour
 56 * translation.
 57 */
 58
 59static void
 60rfbInitTrueColourSingleTableOUT (char **table, rfbPixelFormat *in,
 61                                 rfbPixelFormat *out)
 62{
 63    int i;
 64    int inRed, inGreen, inBlue, outRed, outGreen, outBlue;
 65    OUT_T *t;
 66    int nEntries = 1 << in->bitsPerPixel;
 67
 68    if (*table) free(*table);
 69    *table = (char *)malloc(nEntries * sizeof(OUT_T));
 70    t = (OUT_T *)*table;
 71
 72    for (i = 0; i < nEntries; i++) {
 73        inRed   = (i >> in->redShift)   & in->redMax;
 74        inGreen = (i >> in->greenShift) & in->greenMax;
 75        inBlue  = (i >> in->blueShift)  & in->blueMax;
 76
 77        outRed   = (inRed   * out->redMax   + in->redMax / 2)   / in->redMax;
 78        outGreen = (inGreen * out->greenMax + in->greenMax / 2) / in->greenMax;
 79        outBlue  = (inBlue  * out->blueMax  + in->blueMax / 2)  / in->blueMax;
 80
 81        t[i] = ((outRed   << out->redShift)   |
 82                (outGreen << out->greenShift) |
 83                (outBlue  << out->blueShift));
 84#if (OUT != 8)
 85        if (out->bigEndian != in->bigEndian) {
 86            t[i] = SwapOUT(t[i]);
 87        }
 88#endif
 89    }
 90}
 91
 92
 93/*
 94 * rfbInitTrueColourRGBTables sets up three separate lookup tables for the
 95 * red, green and blue values.
 96 */
 97
 98static void
 99rfbInitTrueColourRGBTablesOUT (char **table, rfbPixelFormat *in,
100                               rfbPixelFormat *out)
101{
102    OUT_T *redTable;
103    OUT_T *greenTable;
104    OUT_T *blueTable;
105
106    if (*table) free(*table);
107    *table = (char *)malloc((in->redMax + in->greenMax + in->blueMax + 3)
108                            * sizeof(OUT_T));
109    redTable = (OUT_T *)*table;
110    greenTable = redTable + in->redMax + 1;
111    blueTable = greenTable + in->greenMax + 1;
112
113    rfbInitOneRGBTableOUT (redTable, in->redMax, out->redMax,
114                           out->redShift, (out->bigEndian != in->bigEndian));
115    rfbInitOneRGBTableOUT (greenTable, in->greenMax, out->greenMax,
116                           out->greenShift, (out->bigEndian != in->bigEndian));
117    rfbInitOneRGBTableOUT (blueTable, in->blueMax, out->blueMax,
118                           out->blueShift, (out->bigEndian != in->bigEndian));
119}
120
121static void
122rfbInitOneRGBTableOUT (OUT_T *table, int inMax, int outMax, int outShift,
123                       int swap)
124{
125    int i;
126    int nEntries = inMax + 1;
127
128    for (i = 0; i < nEntries; i++) {
129        table[i] = ((i * outMax + inMax / 2) / inMax) << outShift;
130#if (OUT != 8)
131        if (swap) {
132            table[i] = SwapOUT(table[i]);
133        }
134#endif
135    }
136}
137
138#undef OUT_T
139#undef SwapOUT
140#undef rfbInitTrueColourSingleTableOUT
141#undef rfbInitTrueColourRGBTablesOUT
142#undef rfbInitOneRGBTableOUT