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/*
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 * tableinittctemplate.c - template for initialising lookup tables for
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 * truecolour to truecolour translation.
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 *
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 * This file shouldn't be compiled.  It is included multiple times by
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 * translate.c, each time with a different definition of the macro OUTBPP.
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 * For each value of OUTBPP, this file defines two functions for initialising
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 * lookup tables.  One is for truecolour translation using a single lookup
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 * table, the other is for truecolour translation using three separate
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 * lookup tables for the red, green and blue values.
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 *
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 * I know this code isn't nice to read because of all the macros, but
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 * efficiency is important here.
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 */
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#if !defined(OUTBPP)
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#error "This file shouldn't be compiled."
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#error "It is included as part of translate.c"
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#endif
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#define OUT_T CONCAT2E(CARD,OUTBPP)
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#define SwapOUT(x) CONCAT2E(Swap,OUTBPP) (x)
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#define rfbInitTrueColourSingleTableOUT \
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				CONCAT2E(rfbInitTrueColourSingleTable,OUTBPP)
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#define rfbInitTrueColourRGBTablesOUT CONCAT2E(rfbInitTrueColourRGBTables,OUTBPP)
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#define rfbInitOneRGBTableOUT CONCAT2E(rfbInitOneRGBTable,OUTBPP)
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static void
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rfbInitOneRGBTableOUT (OUT_T *table, int inMax, int outMax, int outShift,
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		       int swap);
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/*
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 * rfbInitTrueColourSingleTable sets up a single lookup table for truecolour
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 * translation.
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 */
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static void
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rfbInitTrueColourSingleTableOUT (char **table, rfbPixelFormat *in,
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				 rfbPixelFormat *out)
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{
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    int i;
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    int inRed, inGreen, inBlue, outRed, outGreen, outBlue;
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    OUT_T *t;
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    int nEntries = 1 << in->bitsPerPixel;
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    if (*table) free(*table);
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    *table = (char *)malloc(nEntries * sizeof(OUT_T));
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	if (table == NULL) return;
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    t = (OUT_T *)*table;
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    for (i = 0; i < nEntries; i++) {
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	inRed   = (i >> in->redShift)   & in->redMax;
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	inGreen = (i >> in->greenShift) & in->greenMax;
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	inBlue  = (i >> in->blueShift)  & in->blueMax;
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	outRed   = (inRed   * out->redMax   + in->redMax / 2)   / in->redMax;
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	outGreen = (inGreen * out->greenMax + in->greenMax / 2) / in->greenMax;
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	outBlue  = (inBlue  * out->blueMax  + in->blueMax / 2)  / in->blueMax;
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	t[i] = ((outRed   << out->redShift)   |
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		(outGreen << out->greenShift) |
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		(outBlue  << out->blueShift));
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#if (OUTBPP != 8)
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	if (out->bigEndian != in->bigEndian) {
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	    t[i] = SwapOUT(t[i]);
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	}
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#endif
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    }
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}
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/*
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 * rfbInitTrueColourRGBTables sets up three separate lookup tables for the
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 * red, green and blue values.
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 */
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static void
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rfbInitTrueColourRGBTablesOUT (char **table, rfbPixelFormat *in,
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			       rfbPixelFormat *out)
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{
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    OUT_T *redTable;
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    OUT_T *greenTable;
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    OUT_T *blueTable;
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    if (*table) free(*table);
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    *table = (char *)malloc((in->redMax + in->greenMax + in->blueMax + 3)
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			    * sizeof(OUT_T));
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    redTable = (OUT_T *)*table;
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    greenTable = redTable + in->redMax + 1;
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    blueTable = greenTable + in->greenMax + 1;
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    rfbInitOneRGBTableOUT (redTable, in->redMax, out->redMax,
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			   out->redShift, (out->bigEndian != in->bigEndian));
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    rfbInitOneRGBTableOUT (greenTable, in->greenMax, out->greenMax,
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			   out->greenShift, (out->bigEndian != in->bigEndian));
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    rfbInitOneRGBTableOUT (blueTable, in->blueMax, out->blueMax,
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			   out->blueShift, (out->bigEndian != in->bigEndian));
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}
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static void
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rfbInitOneRGBTableOUT (OUT_T *table, int inMax, int outMax, int outShift,
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		       int swap)
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{
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    int i;
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    int nEntries = inMax + 1;
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    for (i = 0; i < nEntries; i++) {
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	table[i] = ((i * outMax + inMax / 2) / inMax) << outShift;
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#if (OUTBPP != 8)
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	if (swap) {
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	    table[i] = SwapOUT(table[i]);
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	}
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#endif
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    }
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}
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#undef OUT_T
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#undef SwapOUT
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#undef rfbInitTrueColourSingleTableOUT
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#undef rfbInitTrueColourRGBTablesOUT
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#undef rfbInitOneRGBTableOUT
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