Edit
IABSD.fr/xenocara/lib/libX11/src/xcms/HVCGcV.c
matthieu
- lib/libX11/src/xcms/HVCGcV.c
-
/* * 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. TekColor is a * trademark of Tektronix, Inc. The term "TekHVC" designates a particular * color space that is the subject of U.S. Patent No. 4,985,853 (equivalent * foreign patents pending). 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: * * 1. This copyright, permission, and disclaimer notice is reproduced in * all copies of this software and any modification thereof and in * supporting documentation; * 2. Any color-handling application which displays TekHVC color * cooordinates identifies these as TekHVC color coordinates in any * interface that displays these coordinates and in any associated * documentation; * 3. The term "TekHVC" is always used, and is only used, in association * with the mathematical derivations of the TekHVC Color Space, * including those provided in this file and any equivalent pathways and * mathematical derivations, regardless of digital (e.g., floating point * or integer) representation. * * 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 * TekHVCGcV.c * * DESCRIPTION * Source for XcmsTekHVCClipV() gamut compression routine. * */ #ifdef HAVE_CONFIG_H #include <config.h> #endif #include "Xlibint.h" #include "Xcmsint.h" #include "Cv.h" /************************************************************************ * * * PUBLIC ROUTINES * * * ************************************************************************/ /* * NAME * XcmsTekHVCClipV - Return the closest value * * SYNOPSIS */ /* ARGSUSED */ Status XcmsTekHVCClipV ( XcmsCCC ccc, XcmsColor *pColors_in_out, unsigned int nColors, unsigned int i, Bool *pCompressed) /* * DESCRIPTION * Return the closest value for a specific hue and chroma. * This routine takes any color as input and outputs * a CIE XYZ color. * * Since this routine works with the value within * pColor_in_out intermediate results may be returned * even though it may be invalid. * * RETURNS * XcmsFailure - Failure * XcmsSuccess - Succeeded * */ { XcmsColor *pColor; XcmsColor hvc_max; XcmsCCCRec myCCC; Status retval; /* * Insure TekHVC installed */ if (XcmsAddColorSpace(&XcmsTekHVCColorSpace) == XcmsFailure) { return(XcmsFailure); } /* Use my own CCC */ memcpy ((char *)&myCCC, (char *)ccc, sizeof(XcmsCCCRec)); myCCC.clientWhitePt.format = XcmsUndefinedFormat;/* Inherit Screen WP */ myCCC.gamutCompProc = (XcmsCompressionProc)NULL;/* no gamut compression */ /* * Color specification passed as input can be assumed to: * 1. Be in XcmsCIEXYZFormat * 2. Already be white point adjusted for the Screen White Point. * This means that the white point now associated with this * color spec is the Screen White Point (even if the * ccc->clientWhitePt differs). */ pColor = pColors_in_out + i; if (ccc->visual->class < StaticColor && FunctionSetOfCCC(ccc) != (XPointer) &XcmsLinearRGBFunctionSet) { /* * GRAY ! */ return(XcmsFailure); } else { /* Convert from CIEXYZ to TekHVC format */ if (_XcmsDIConvertColors(&myCCC, pColor, &myCCC.pPerScrnInfo->screenWhitePt, 1, XcmsTekHVCFormat) == XcmsFailure) { return(XcmsFailure); } /* check to make sure we have a valid TekHVC number */ if (!_XcmsTekHVC_CheckModify (pColor)) { return (XcmsFailure); } /* Step 1: compute the maximum value and chroma for this hue. */ /* This copy may be overkill but it preserves the pixel etc. */ memcpy((char *)&hvc_max, (char *)pColor, sizeof(XcmsColor)); if (_XcmsTekHVCQueryMaxVCRGB (&myCCC, hvc_max.spec.TekHVC.H, &hvc_max, (XcmsRGBi *)NULL) == XcmsFailure) { return (XcmsFailure); } /* Now check and return the appropriate value */ if (pColor->spec.TekHVC.C == hvc_max.spec.TekHVC.C) { /* When the chroma input is equal to the maximum chroma */ /* merely return the value for that chroma. */ pColor->spec.TekHVC.V = hvc_max.spec.TekHVC.V; if (!_XcmsTekHVC_CheckModify (pColor)) { return (XcmsFailure); } retval = _XcmsDIConvertColors(&myCCC, pColor, &myCCC.pPerScrnInfo->screenWhitePt, 1, XcmsCIEXYZFormat); } else if (pColor->spec.TekHVC.C > hvc_max.spec.TekHVC.C) { /* When the chroma input is greater than the maximum chroma */ /* merely return the value and chroma for the given hue. */ pColor->spec.TekHVC.C = hvc_max.spec.TekHVC.C; pColor->spec.TekHVC.V = hvc_max.spec.TekHVC.V; return (XcmsFailure); } else if (pColor->spec.TekHVC.V < hvc_max.spec.TekHVC.V) { /* When the value input is less than the maximum value point */ /* compute the intersection of the line from 0,0 to max_V, max_C */ /* using the chroma input. */ pColor->spec.TekHVC.V = pColor->spec.TekHVC.C * hvc_max.spec.TekHVC.V / hvc_max.spec.TekHVC.C; if (pColor->spec.TekHVC.V >= hvc_max.spec.TekHVC.V) { pColor->spec.TekHVC.C = hvc_max.spec.TekHVC.C; pColor->spec.TekHVC.V = hvc_max.spec.TekHVC.V; } if (!_XcmsTekHVC_CheckModify (pColor)) { return (XcmsFailure); } retval = _XcmsDIConvertColors(&myCCC, pColor, &myCCC.pPerScrnInfo->screenWhitePt, 1, XcmsCIEXYZFormat); } else { /* When the value input is greater than the maximum value point */ /* use HvcMaxValue to find the maximum value for the given chroma. */ if (pColor->format != XcmsTekHVCFormat) { if (_XcmsDIConvertColors(ccc, pColor, &ccc->pPerScrnInfo->screenWhitePt, 1, XcmsCIEXYZFormat) == XcmsFailure) { return(XcmsFailure); } } if (XcmsTekHVCQueryMaxV(&myCCC, pColor->spec.TekHVC.H, pColor->spec.TekHVC.C, pColor) == XcmsFailure) { return (XcmsFailure); } retval = _XcmsDIConvertColors(&myCCC, pColor, &myCCC.pPerScrnInfo->screenWhitePt, 1, XcmsCIEXYZFormat); } if (retval != XcmsFailure && pCompressed != NULL) { *(pCompressed + i) = True; } return(retval); } }