cdesktopenv/cde/lib/DtHelp/il/ilpalette.c

208 lines
7.8 KiB
C

/*
* CDE - Common Desktop Environment
*
* Copyright (c) 1993-2012, The Open Group. All rights reserved.
*
* These libraries and programs are free software; you can
* redistribute them and/or modify them under the terms of the GNU
* Lesser General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* These libraries and programs are distributed in the hope that
* they will be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with these librararies and programs; if not, write
* to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
* Floor, Boston, MA 02110-1301 USA
*/
/* $XConsortium: ilpalette.c /main/3 1995/10/23 15:58:32 rswiston $ */
/**---------------------------------------------------------------------
***
*** (c)Copyright 1991 Hewlett-Packard Co.
***
*** RESTRICTED RIGHTS LEGEND
*** Use, duplication, or disclosure by the U.S. Government is subject to
*** restrictions as set forth in sub-paragraph (c)(1)(ii) of the Rights in
*** Technical Data and Computer Software clause in DFARS 252.227-7013.
*** Hewlett-Packard Company
*** 3000 Hanover Street
*** Palo Alto, CA 94304 U.S.A.
*** Rights for non-DOD U.S. Government Departments and Agencies are as set
*** forth in FAR 52.227-19(c)(1,2).
***
***-------------------------------------------------------------------*/
/* /ilc/ilpalette.c : Code for handling IL_PALETTE images.
Mostly converters to other types (e.g. to RGB), referenced by
/ilc/ilconvert.c
*/
#include "ilint.h"
#include "ilpipelem.h"
#include "ilconvert.h"
/* ----------------------- ilPaletteToRGBByte ------------------------- */
/* Converts byte palette image to RGB, each a byte
Input image: uncompressed IL_PALETTE, any # of levels, IL_FORMAT_BYTE.
Output image: IL_DES_RGB, IL_FORMAT_3BYTE_PIXEL.
*/
/* Private data, inited by Init() function.
"palette" is inited when the element is added. It is a copy of the palette,
as longwords: <8 unused> <8 blue> <8 green> <8 red> for each value 0..255
for faster lookup of each palette pixel. Each 8 is the upper 8 bits of
the palette entry.
*/
typedef struct {
long nPixelsM1; /* width - 1 of src/dst images */
long srcRowBytes; /* bytes/row of src image */
ilPtr pSrcPixels; /* ptr to start of src pixels */
long dstRowBytes; /* bytes/row of dst image */
ilPtr pDstPixels; /* ptr to start of dst pixels */
unsigned short *pPalette; /* ptr to palette, set by AddElement() */
unsigned long palette [256]; /* copy of palette: see above */
ilBool firstStrip; /* true if first strip to Execute() */
} ilPaletteToRGBPrivRec, *ilPaletteToRGBPrivPtr;
/* AddElement() function, called by ilConvert() after the pipe element is added.
Merely copy the given pPalette into private.
*/
static ilError ilAddElementPaletteToRGBByte (
ilPaletteToRGBPrivPtr pPriv,
unsigned short *pPalette
)
{
pPriv->pPalette = pPalette;
return IL_OK;
}
/* Init() function: init values in private */
static ilError ilInitPaletteToRGBByte (
ilPaletteToRGBPrivPtr pPriv,
ilImageInfo *pSrcImage,
ilImageInfo *pDstImage
)
{
pPriv->nPixelsM1 = pSrcImage->width - 1;
pPriv->srcRowBytes = pSrcImage->plane[0].nBytesPerRow;
pPriv->pSrcPixels = pSrcImage->plane[0].pPixels;
pPriv->dstRowBytes = pDstImage->plane[0].nBytesPerRow;
pPriv->pDstPixels = pDstImage->plane[0].pPixels;
pPriv->firstStrip = TRUE;
return IL_OK;
}
/* Called by Execute() to setup "palette" in private */
static void ilInitPackedPalette (
ilPaletteToRGBPrivPtr pPriv
)
{
register int i;
register unsigned long *pPacked, packed;
register unsigned short *pRed, *pGreen, *pBlue, temp;
/* Pack the upper 8 bits of the rgb value, with blue in the high order bits. */
pPacked = pPriv->palette;
pRed = &pPriv->pPalette [0 * 256];
pGreen = &pPriv->pPalette [1 * 256];
pBlue = &pPriv->pPalette [2 * 256];
for (i = 0; i < 256; i++) {
temp = *pBlue++;
packed = temp >> 8;
packed <<= 8;
temp = *pGreen++;
packed |= temp >> 8;
packed <<= 8;
temp = *pRed++;
packed |= temp >> 8;
*pPacked++ = packed;
}
}
/* Execute() function: convert the given # of src lines.
Lookup each palette byte (0..255) and get a long which looks like:
<8 unused> <8 blue> <8 green> <8 red>
output the lower 8 bits, then shift to get RGB.
*/
static ilError ilExecutePaletteToRGBByte (
ilExecuteData *pData,
long dstLine,
long *pNLines /* ignored on input */
)
{
ilPaletteToRGBPrivPtr pPriv;
long srcRowBytes, dstRowBytes, nPixelsM1;
ilPtr pSrcLine, pDstLine;
register ilPtr pSrc, pDst;
register unsigned long rgb, *pPackedPalette;
register long nLinesM1, nPixelsM1Temp;
/* If firstStrip, init the packed palette in private */
pPriv = (ilPaletteToRGBPrivPtr)pData->pPrivate;
if (pPriv->firstStrip) {
ilInitPackedPalette (pPriv);
pPriv->firstStrip = FALSE;
}
/* Setup src,dst line ptrs and rowBytes, and nLines/PixelsM1 ("minus 1");
exit if no lines or pixels.
*/
srcRowBytes = pPriv->srcRowBytes;
pSrcLine = pPriv->pSrcPixels + pData->srcLine * srcRowBytes;
dstRowBytes = pPriv->dstRowBytes;
pDstLine = pPriv->pDstPixels + dstLine * dstRowBytes;
nPixelsM1 = pPriv->nPixelsM1;
if (nPixelsM1 < 0)
return;
nLinesM1 = *pNLines;
if (nLinesM1 <= 0)
return;
nLinesM1--;
/* For each src byte: get a long from the cvt'd palette table, then take
the low eight bits to get r,g,b, shifting down by 8 to get next component.
*/
pPackedPalette = pPriv->palette;
do {
pSrc = pSrcLine;
pSrcLine += srcRowBytes;
pDst = pDstLine;
pDstLine += dstRowBytes;
nPixelsM1Temp = nPixelsM1;
do {
rgb = pPackedPalette [*pSrc++];
*pDst++ = (ilByte)rgb; /* red */
rgb >>= 8;
*pDst++ = (ilByte)rgb; /* green */
rgb >>= 8;
*pDst++ = (ilByte)rgb; /* blue */
} while (--nPixelsM1Temp >= 0);
} while (--nLinesM1 >= 0);
return IL_OK;
}
/* Table exported to ilConvert(), declared in /ilc/ilconvert.h .
*/
IL_PRIVATE ilConvertRec _ilPaletteToRGBByte = {
IL_NPF, /* CheckFormat() */
IL_STD_FORMAT_BYTE, /* srcFormatCode */
ilAddElementPaletteToRGBByte, /* AddElement() */
IL_DES_RGB, /* pDstDes */
IL_FORMAT_3BYTE_PIXEL, /* pDstFormat */
sizeof (ilPaletteToRGBPrivRec), /* nBytesPrivate */
ilInitPaletteToRGBByte, /* Init() */
IL_NPF, /* Cleanup() */
IL_NPF, /* Destroy() */
ilExecutePaletteToRGBByte /* Execute() */
};