aboutsummaryrefslogtreecommitdiff
path: root/libX11/src/xcms/HVCMxC.c
diff options
context:
space:
mode:
Diffstat (limited to 'libX11/src/xcms/HVCMxC.c')
-rw-r--r--libX11/src/xcms/HVCMxC.c245
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);
+}