4.4BSD/usr/src/contrib/X11R5-lib/lib/X/XcmsXRGB.c
/* $XConsortium: XcmsXRGB.c,v 1.5 91/07/22 15:53:56 rws Exp $" */
/*
* Code and supporting documentation (c) Copyright 1990 1991 Tektronix, Inc.
* All Rights Reserved
*
* This file is a component of an X Window System-specific implementation
* of Xcms based on the TekColor Color Management System. Permission is
* hereby granted to use, copy, modify, sell, and otherwise distribute this
* software and its documentation for any purpose and without fee, provided
* that this copyright, permission, and disclaimer notice is reproduced in
* all copies of this software and in supporting documentation. TekColor
* is a trademark of Tektronix, Inc.
*
* Tektronix makes no representation about the suitability of this software
* for any purpose. It is provided "as is" and with all faults.
*
* TEKTRONIX DISCLAIMS ALL WARRANTIES APPLICABLE TO THIS SOFTWARE,
* INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE. IN NO EVENT SHALL TEKTRONIX BE LIABLE FOR ANY
* SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA, OR PROFITS, WHETHER IN AN ACTION OF
* CONTRACT, NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR THE PERFORMANCE OF THIS SOFTWARE.
*
*
* NAME
* XcmsRtoX.c
*
* DESCRIPTION
* Convert color specifications in XcmsRGB format in one array of
* XcmsColor structures to RGB in an array of XColor structures.
*
*
*/
#include "Xlibint.h"
#include "Xcmsint.h"
#if __STDC__
#define Const const
#else
#define Const /**/
#endif
/*
* LOCAL VARIABLES
*/
static unsigned short Const MASK[17] = {
0x0000, /* 0 bitsPerRGB */
0x8000, /* 1 bitsPerRGB */
0xc000, /* 2 bitsPerRGB */
0xe000, /* 3 bitsPerRGB */
0xf000, /* 4 bitsPerRGB */
0xf800, /* 5 bitsPerRGB */
0xfc00, /* 6 bitsPerRGB */
0xfe00, /* 7 bitsPerRGB */
0xff00, /* 8 bitsPerRGB */
0xff80, /* 9 bitsPerRGB */
0xffc0, /* 10 bitsPerRGB */
0xffe0, /* 11 bitsPerRGB */
0xfff0, /* 12 bitsPerRGB */
0xfff8, /* 13 bitsPerRGB */
0xfffc, /* 14 bitsPerRGB */
0xfffe, /* 15 bitsPerRGB */
0xffff /* 16 bitsPerRGB */
};
/************************************************************************
* *
* API PRIVATE ROUTINES *
* *
************************************************************************/
/*
* NAME
* _XcmsRGB_to_XColor -
*
* SYNOPSIS
*/
void
_XcmsRGB_to_XColor(pColors, pXColors, nColors)
XcmsColor *pColors;
XColor *pXColors;
unsigned int nColors;
/*
* DESCRIPTION
* Translates a color specification in XcmsRGBFormat in a XcmsColor
* structure to an XColor structure.
*
* RETURNS
* void.
*/
{
for (; nColors--; pXColors++, pColors++) {
pXColors->pixel = pColors->pixel;
pXColors->red = pColors->spec.RGB.red;
pXColors->green = pColors->spec.RGB.green;
pXColors->blue = pColors->spec.RGB.blue;
pXColors->flags = (DoRed | DoGreen | DoBlue);
}
}
/*
* NAME
* _XColor_to_XcmsRGB
*
* SYNOPSIS
*/
void
_XColor_to_XcmsRGB(ccc, pXColors, pColors, nColors)
XcmsCCC ccc;
XColor *pXColors;
XcmsColor *pColors;
unsigned int nColors;
/*
* DESCRIPTION
* Translates an RGB color specification in an XColor
* structure to an XcmsRGB structure.
*
* IMPORTANT NOTE: Bit replication that may have been caused
* with ResolveColor() routine in the X Server is undone
* here if requested! For example, if red = 0xcaca and the
* bits_per_rgb is 8, then spec.RGB.red will be 0xca00.
*
* RETURNS
* void
*/
{
int bits_per_rgb = ccc->visual->bits_per_rgb;
for (; nColors--; pXColors++, pColors++) {
pColors->spec.RGB.red = (pXColors->red & MASK[bits_per_rgb]);
pColors->spec.RGB.green = (pXColors->green & MASK[bits_per_rgb]);
pColors->spec.RGB.blue = (pXColors->blue & MASK[bits_per_rgb]);
pColors->format = XcmsRGBFormat;
pColors->pixel = pXColors->pixel;
}
}
/*
* NAME
* _XcmsResolveColor
*
* SYNOPSIS
*/
void
_XcmsResolveColor(ccc, pXcmsColor)
XcmsCCC ccc;
XcmsColor *pXcmsColor;
/*
* DESCRIPTION
* Uses the X Server ResolveColor() algorithm to
* modify values to closest values supported by hardware.
* Old algorithm simply masked low-order bits. The new algorithm
* has the effect of replicating significant bits into lower order
* bits in order to stretch the hardware value into all 16 bits.
*
* On a display with N-bit DACs, the "hardware" color is computed as:
*
* ((unsignedlong)(ClientValue >> (16-N)) * 0xFFFF) / ((1 << N) - 1)
*
*
* RETURNS
* void.
*/
{
int shift;
int max_color;
shift = 16 - ccc->visual->bits_per_rgb;
max_color = (1 << ccc->visual->bits_per_rgb) - 1;
pXcmsColor->spec.RGB.red =
((unsigned long)(pXcmsColor->spec.RGB.red >> shift) * 0xFFFF)
/ max_color;
pXcmsColor->spec.RGB.green =
((unsigned long)(pXcmsColor->spec.RGB.green >> shift) * 0xFFFF)
/ max_color;
pXcmsColor->spec.RGB.blue =
((unsigned long)(pXcmsColor->spec.RGB.blue >> shift) * 0xFFFF)
/ max_color;
}
/*
* NAME
* _XcmsUnresolveColor
*
* SYNOPSIS
*/
void
_XcmsUnresolveColor(ccc, pColor)
XcmsCCC ccc;
XcmsColor *pColor;
/*
* DESCRIPTION
* Masks out insignificant bits.
*
* RETURNS
* void.
*
* ASSUMPTIONS
* format == XcmsRGBFormat
*/
{
int bits_per_rgb = ccc->visual->bits_per_rgb;
pColor->spec.RGB.red &= MASK[bits_per_rgb];
pColor->spec.RGB.green &= MASK[bits_per_rgb];
pColor->spec.RGB.blue &= MASK[bits_per_rgb];
}
/*
* NAME
* _XUnresolveColor
*
* SYNOPSIS
*/
void
_XUnresolveColor(ccc, pXColor)
XcmsCCC ccc;
XColor *pXColor;
/*
* DESCRIPTION
* Masks out insignificant bits.
*
* RETURNS
* void.
*/
{
int bits_per_rgb = ccc->visual->bits_per_rgb;
pXColor->red &= MASK[bits_per_rgb];
pXColor->green &= MASK[bits_per_rgb];
pXColor->blue &= MASK[bits_per_rgb];
}