LibVNCServer/LibVNCClient
 All Data Structures Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
tableinittctemplate.c
Go to the documentation of this file.
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 
49 static void
50 rfbInitOneRGBTableOUT (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 
59 static void
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 
98 static void
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 
121 static void
122 rfbInitOneRGBTableOUT (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