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Diffstat (limited to 'libX11/src/xcms/HVCMxC.c')
-rw-r--r-- | libX11/src/xcms/HVCMxC.c | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/libX11/src/xcms/HVCMxC.c b/libX11/src/xcms/HVCMxC.c new file mode 100644 index 000000000..6e6923704 --- /dev/null +++ b/libX11/src/xcms/HVCMxC.c @@ -0,0 +1,245 @@ +/* $Xorg: HVCMxC.c,v 1.3 2000/08/17 19:44:37 cpqbld 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. 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 + * TekHVCMxC.c + * + * DESCRIPTION + * Source for the XcmsTekHVCQueryMaxC() gamut boudary + * querying routine. + * + */ +/* $XFree86: xc/lib/X11/HVCMxC.c,v 1.4 2003/04/13 19:22:16 dawes Exp $ */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif +#include "Xlibint.h" +#include "Xcmsint.h" +#include <math.h> +#include "Cv.h" + +/* + * DEFINES + */ +#define MAXBISECTCOUNT 100 +#define EPS 0.001 + + +/************************************************************************ + * * + * PUBLIC ROUTINES * + * * + ************************************************************************/ + +/* + * NAME + * XcmsTekHVCQueryMaxC - Compute the maximum chroma for a hue and value + * + * SYNOPSIS + */ +Status +XcmsTekHVCQueryMaxC( + XcmsCCC ccc, + XcmsFloat hue, + XcmsFloat value, + XcmsColor *pColor_return) +/* + * DESCRIPTION + * Return the maximum chroma for a specific hue and value. + * The returned format is in XcmsTekHVCFormat. + * + * + * ASSUMPTIONS + * This routine assumes that the white point associated with + * the color specification is the Screen White Point. The + * Screen White Point will also be associated with the + * returned color specification. + * + * RETURNS + * XcmsFailure - Failure + * XcmsSuccess - Succeeded + * + */ +{ + XcmsCCCRec myCCC; + XcmsColor tmp; + XcmsColor max_vc; + XcmsRGBi rgb_saved; + int nCount, nMaxCount; + XcmsFloat nValue, savedValue, lastValue, lastChroma, prevValue; + XcmsFloat maxDist, nT, rFactor; + XcmsFloat ftmp1, ftmp2; + + /* + * Check Arguments + */ + if (ccc == NULL || pColor_return == NULL) { + return(XcmsFailure); + } + + /* + * 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 white Pt */ + myCCC.gamutCompProc = (XcmsCompressionProc)NULL;/* no gamut comp func */ + + tmp.spec.TekHVC.H = hue; + tmp.spec.TekHVC.V = value; + tmp.spec.TekHVC.C = 100.0; + tmp.pixel = pColor_return->pixel; + tmp.format = XcmsTekHVCFormat; + + /* check to make sure we have a valid TekHVC number */ + if (!_XcmsTekHVC_CheckModify(&tmp)) { + return(XcmsFailure); + } + + /* Step 1: compute the maximum value and chroma for this hue. */ + memcpy((char *)&max_vc, (char *)&tmp, sizeof(XcmsColor)); + if (_XcmsTekHVCQueryMaxVCRGB(&myCCC, hue, &max_vc, &rgb_saved) + == XcmsFailure) { + return(XcmsFailure); + } + + /* Step 2: If the value is less than the value for the maximum */ + /* value, chroma point then the chroma is on the line */ + /* from max_vc to 0,0. */ + if (value <= max_vc.spec.TekHVC.V) { + tmp.spec.TekHVC.C = value + * max_vc.spec.TekHVC.C / max_vc.spec.TekHVC.V; + if (_XcmsTekHVC_CheckModify (&tmp)) { + memcpy((char *)pColor_return, (char *)&tmp, sizeof(XcmsColor)); + return(XcmsSuccess); + } else { + return(XcmsFailure); + } + } else { + /* must do a bisection here to compute the maximum chroma */ + /* save the structure input so that any elements that */ + /* are not touched are recopied later in the routine. */ + nValue = savedValue = value; + lastChroma = -1.0; + lastValue = -1.0; + nMaxCount = MAXBISECTCOUNT; + maxDist = 100.0 - max_vc.spec.TekHVC.V; + rFactor = 1.0; + + for (nCount = 0; nCount < nMaxCount; nCount++) { + prevValue = lastValue; + lastValue = tmp.spec.TekHVC.V; + lastChroma = tmp.spec.TekHVC.C; + nT = (nValue - max_vc.spec.TekHVC.V) / maxDist * rFactor; + tmp.spec.RGBi.red = rgb_saved.red * (1.0 - nT) + nT; + tmp.spec.RGBi.green = rgb_saved.green * (1.0 - nT) + nT; + tmp.spec.RGBi.blue = rgb_saved.blue * (1.0 - nT) + nT; + tmp.format = XcmsRGBiFormat; + + /* convert from RGB to HVC */ + if (_XcmsConvertColorsWithWhitePt(&myCCC, &tmp, + &myCCC.pPerScrnInfo->screenWhitePt, 1, XcmsTekHVCFormat, + (Bool *) NULL) == XcmsFailure) { + return(XcmsFailure); + } + + /* Now check the return against what is expected */ + if (tmp.spec.TekHVC.V <= savedValue + EPS && + tmp.spec.TekHVC.V >= savedValue - EPS) { + /* make sure to return the input hue */ + tmp.spec.TekHVC.H = hue; + if (_XcmsTekHVC_CheckModify (&tmp)) { + memcpy((char *)pColor_return, (char *)&tmp, sizeof(XcmsColor)); + return(XcmsSuccess); + } else { + return(XcmsFailure); + } + } + nValue += savedValue - tmp.spec.TekHVC.V; + if (nValue < max_vc.spec.TekHVC.V) { + nValue = max_vc.spec.TekHVC.V; + rFactor *= 0.5; /* selective relaxation employed */ + } else if (nValue > 100.0) { + /* make sure to return the input hue */ + tmp.spec.TekHVC.H = hue; + /* avoid using fabs */ + ftmp1 = lastValue - savedValue; + if (ftmp1 < 0.0) + ftmp1 = -ftmp1; + ftmp2 = tmp.spec.TekHVC.V - savedValue; + if (ftmp2 < 0.0) + ftmp2 = -ftmp2; + if (ftmp1 < ftmp2) { + tmp.spec.TekHVC.V = lastValue; + tmp.spec.TekHVC.C = lastChroma; + } + if (_XcmsTekHVC_CheckModify (&tmp)) { + memcpy((char *)pColor_return, (char *)&tmp, sizeof(XcmsColor)); + return(XcmsSuccess); + } else { + return(XcmsFailure); + } + } else if (tmp.spec.TekHVC.V <= prevValue + EPS && + tmp.spec.TekHVC.V >= prevValue - EPS) { + rFactor *= 0.5; /* selective relaxation employed */ + } + } + if (nCount >= nMaxCount) { + /* avoid using fabs */ + ftmp1 = lastValue - savedValue; + if (ftmp1 < 0.0) + ftmp1 = -ftmp1; + ftmp2 = tmp.spec.TekHVC.V - savedValue; + if (ftmp2 < 0.0) + ftmp2 = -ftmp2; + if (ftmp1 < ftmp2) { + tmp.spec.TekHVC.V = lastValue; + tmp.spec.TekHVC.C = lastChroma; + } + } + } + /* make sure to return the input hue */ + tmp.spec.TekHVC.H = hue; + memcpy((char *)pColor_return, (char *)&tmp, sizeof(XcmsColor)); + return(XcmsSuccess); +} |