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diff --git a/xc/lib/X11/xyY.c b/xc/lib/X11/xyY.c
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+/* $XConsortium: xyY.c,v 1.10 93/09/07 21:33:40 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
+ *		CIExyY.c
+ *
+ *	DESCRIPTION
+ *		This file contains routines that support the CIE xyY
+ *		color space to include conversions to and from the CIE
+ *		XYZ space.
+ *
+ *	DOCUMENTATION
+ *		"TekColor Color Management System, System Implementor's Manual"
+ */
+/* $XFree86: xc/lib/X11/xyY.c,v 1.2 1999/05/09 10:50:43 dawes Exp $ */
+
+#include <stdio.h>
+#include <X11/Xos.h>
+#include "Xlibint.h"
+#include "Xcmsint.h"
+
+/*
+ *	DEFINES
+ */
+#define EPS 0.00001	/* some extremely small number */
+#ifdef DBL_EPSILON
+#  define XMY_DBL_EPSILON DBL_EPSILON
+#else
+#  define XMY_DBL_EPSILON 0.00001
+#endif
+
+/*
+ *	EXTERNS
+ */
+
+extern char _XcmsCIExyY_prefix[];
+
+/* CvCols.c */
+extern Status _XcmsDIConvertColors();
+
+/* XYZ.c */
+extern Status _XcmsCIEXYZ_ValidSpec();
+
+/*
+ *	FORWARD DECLARATIONS
+ */
+
+static int CIExyY_ParseString();
+static Status XcmsCIExyY_ValidSpec();
+
+
+/*
+ *	LOCAL VARIABLES
+ */
+
+    /*
+     * NULL terminated list of functions applied to get from CIExyY to CIEXYZ
+     */
+static XcmsConversionProc Fl_CIExyY_to_CIEXYZ[] = {
+    XcmsCIExyYToCIEXYZ,
+    NULL
+};
+
+    /*
+     * NULL terminated list of functions applied to get from CIEXYZ to CIExyY
+     */
+static XcmsConversionProc Fl_CIEXYZ_to_CIExyY[] = {
+    XcmsCIEXYZToCIExyY,
+    NULL
+};
+
+
+/*
+ *	GLOBALS
+ */
+
+    /*
+     * CIE xyY Color Space
+     */
+XcmsColorSpace	XcmsCIExyYColorSpace =
+    {
+	_XcmsCIExyY_prefix,	/* prefix */
+	XcmsCIExyYFormat,		/* id */
+	CIExyY_ParseString,	/* parseString */
+	Fl_CIExyY_to_CIEXYZ,	/* to_CIEXYZ */
+	Fl_CIEXYZ_to_CIExyY,	/* from_CIEXYZ */
+	1
+    };
+
+
+
+/************************************************************************
+ *									*
+ *			 PRIVATE ROUTINES				*
+ *									*
+ ************************************************************************/
+
+/*
+ *	NAME
+ *		CIExyY_ParseString
+ *
+ *	SYNOPSIS
+ */
+static int
+CIExyY_ParseString(spec, pColor)
+    register char *spec;
+    XcmsColor *pColor;
+/*
+ *	DESCRIPTION
+ *		This routines takes a string and attempts to convert
+ *		it into a XcmsColor structure with XcmsCIExyYFormat.
+ *		The assumed CIExyY string syntax is:
+ *		    CIExyY:<x>/<y>/<Y>
+ *		Where x, y, and Y are in string input format for floats
+ *		consisting of:
+ *		    a. an optional sign
+ *		    b. a string of numbers possibly containing a decimal point,
+ *		    c. an optional exponent field containing an 'E' or 'e'
+ *			followed by a possibly signed integer string.
+ *
+ *	RETURNS
+ *		0 if failed, non-zero otherwise.
+ */
+{
+    int n;
+    char *pchar;
+
+    if ((pchar = strchr(spec, ':')) == NULL) {
+	return(XcmsFailure);
+    }
+    n = (int)(pchar - spec);
+
+    /*
+     * Check for proper prefix.
+     */
+    if (strncmp(spec, _XcmsCIExyY_prefix, n) != 0) {
+	return(XcmsFailure);
+    }
+
+    /*
+     * Attempt to parse the value portion.
+     */
+    if (sscanf(spec + n + 1, "%lf/%lf/%lf",
+	    &pColor->spec.CIExyY.x,
+	    &pColor->spec.CIExyY.y,
+	    &pColor->spec.CIExyY.Y) != 3) {
+	return(XcmsFailure);
+    }
+    pColor->format = XcmsCIExyYFormat;
+    pColor->pixel = 0;
+    return(XcmsCIExyY_ValidSpec(pColor));
+}
+
+
+
+/************************************************************************
+ *									*
+ *			 PUBLIC ROUTINES				*
+ *									*
+ ************************************************************************/
+
+/*
+ *	NAME
+ *		CIExyY_ValidSpec()
+ *
+ *	SYNOPSIS
+ */
+static Status
+XcmsCIExyY_ValidSpec(pColor)
+    XcmsColor *pColor;
+/*
+ *	DESCRIPTION
+ *		Checks a valid CIExyY color specification.
+ *
+ *	RETURNS
+ *		XcmsFailure if invalid.
+ *		XcmsSuccess if valid.
+ *
+ */
+{
+    if (pColor->format != XcmsCIExyYFormat
+	    ||
+	    (pColor->spec.CIExyY.x < 0.0 - XMY_DBL_EPSILON)
+	    ||
+	    (pColor->spec.CIExyY.x > 1.0 + XMY_DBL_EPSILON)
+	    ||
+	    (pColor->spec.CIExyY.y < 0.0 - XMY_DBL_EPSILON)
+	    ||
+	    (pColor->spec.CIExyY.y > 1.0 + XMY_DBL_EPSILON)
+	    ||
+	    (pColor->spec.CIExyY.Y < 0.0 - XMY_DBL_EPSILON)
+	    ||
+	    (pColor->spec.CIExyY.Y > 1.0 + XMY_DBL_EPSILON)) {
+	return(XcmsFailure);
+    }
+    return(XcmsSuccess);
+}
+
+
+/*
+ *	NAME
+ *		XcmsCIExyYToCIEXYZ - convert CIExyY to CIEXYZ
+ *
+ *	SYNOPSIS
+ */
+Status
+XcmsCIExyYToCIEXYZ(ccc, pxyY_WhitePt, pColors_in_out, nColors)
+    XcmsCCC ccc;
+    XcmsColor *pxyY_WhitePt;
+    XcmsColor *pColors_in_out;
+    unsigned int nColors;
+/*
+ *	DESCRIPTION
+ *		Converts color specifications in an array of XcmsColor
+ *		structures from CIExyY format to CIEXYZ format.
+ *
+ *	RETURNS
+ *		XcmsFailure if failed,
+ *		XcmsSuccess if succeeded.
+ */
+{
+    XcmsColor	*pColor = pColors_in_out;
+    XcmsColor	whitePt;
+    XcmsCIEXYZ	XYZ_return;
+    XcmsFloat	div;		/* temporary storage in case divisor is zero */
+    XcmsFloat	u, v, x, y, z;	/* temporary storage */
+    register int i;
+
+    /*
+     * Check arguments
+     */
+    if (pxyY_WhitePt == NULL || pColors_in_out == NULL) {
+	return(XcmsFailure);
+    }
+
+
+    /*
+     * Now convert each XcmsColor structure to CIEXYZ form
+     */
+    for (i = 0; i < nColors; i++, pColor++) {
+	/* Make sure original format is CIExyY and valid */
+	if (!XcmsCIExyY_ValidSpec(pColor)) {
+	    return(XcmsFailure);
+	}
+
+	if ((div = (-2 * pColor->spec.CIExyY.x) + (12 * pColor->spec.CIExyY.y) + 3) == 0.0) {
+	    /* Note that the divisor is zero */
+	    /* This return is abitrary. */
+	    XYZ_return.X = 0;
+	    XYZ_return.Y = 0;
+	    XYZ_return.Z = 0;
+	} else {
+	    /*
+	     * Make sure white point is in CIEXYZ form
+	     */
+	    if (pxyY_WhitePt->format != XcmsCIEXYZFormat) {
+		/* Make copy of the white point because we're going to modify it */
+		memcpy((char *)&whitePt, (char *)pxyY_WhitePt, sizeof(XcmsColor));
+		if (!_XcmsDIConvertColors(ccc, &whitePt, (XcmsColor *)NULL, 1,
+			XcmsCIEXYZFormat)) {
+		    return(XcmsFailure);
+		}
+		pxyY_WhitePt = &whitePt;
+	    }
+
+	    /* Make sure it is a white point, i.e., Y == 1.0 */
+	    if (pxyY_WhitePt->spec.CIEXYZ.Y != 1.0) {
+		return(XcmsFailure);
+	    }
+
+	    /* Convert from xyY to uvY to XYZ */
+	    u = (4 * pColor->spec.CIExyY.x) / div;
+	    v = (9 * pColor->spec.CIExyY.y) / div;
+	    div = (6.0 * u) - (16.0 * v) + 12.0;
+	    if (div == 0.0) {
+		/* Note that the divisor is zero */
+		/* This return is abitrary. */
+		if ((div = (6.0 * whitePt.spec.CIEuvY.u_prime) -
+		           (16.0 * whitePt.spec.CIEuvY.v_prime) + 12.0) == 0.0) {
+		    div = EPS;
+		}
+		x = 9.0 * whitePt.spec.CIEuvY.u_prime / div;
+		y = 4.0 * whitePt.spec.CIEuvY.u_prime / div;
+	    } else {
+		/* convert u, v to small xyz */
+		x = 9.0 * u / div;
+		y = 4.0 * v / div;
+	    }
+	    z = 1.0 - x - y;
+	    if (y == 0.0) y = EPS;	/* Have to worry about divide by 0 */
+	    XYZ_return.Y = pColor->spec.CIExyY.Y;
+	    XYZ_return.X = x * XYZ_return.Y / y;
+	    XYZ_return.Z = z * XYZ_return.Y / y;
+	}
+
+	/* Copy result to pColor */
+	memcpy ((char *)&pColor->spec, (char *)&XYZ_return, sizeof(XcmsCIEXYZ));
+
+	/* Identify that the format is now CIEXYZ */
+	pColor->format = XcmsCIEXYZFormat;
+    }
+    return(XcmsSuccess);
+}
+
+
+/*
+ *	NAME
+ *		XcmsCIEXYZToCIExyY - convert CIEXYZ to CIExyY
+ *
+ *	SYNOPSIS
+ */
+/* ARGSUSED */
+Status
+XcmsCIEXYZToCIExyY(ccc, pxyY_WhitePt, pColors_in_out, nColors)
+    XcmsCCC ccc;
+    XcmsColor *pxyY_WhitePt;
+    XcmsColor *pColors_in_out;
+    unsigned int nColors;
+/*
+ *	DESCRIPTION
+ *		Converts color specifications in an array of XcmsColor
+ *		structures from CIEXYZ format to CIExyY format.
+ *
+ *	RETURNS
+ *		XcmsFailure if failed,
+ *		XcmsSuccess if succeeded.
+ *
+ */
+{
+    XcmsColor	*pColor = pColors_in_out;
+    XcmsCIExyY	xyY_return;
+    XcmsFloat	div;		/* temporary storage in case divisor is zero */
+    register int i;
+
+    /*
+     * Check arguments
+     * 		pxyY_WhitePt ignored
+     */
+    if (pColors_in_out == NULL) {
+	return(XcmsFailure);
+    }
+
+    /*
+     * Now convert each XcmsColor structure to CIEXYZ form
+     */
+    for (i = 0; i < nColors; i++, pColor++) {
+
+	if (!_XcmsCIEXYZ_ValidSpec(pColor)) {
+	    return(XcmsFailure);
+	}
+	/* Now convert for XYZ to xyY */
+	if ((div = pColor->spec.CIEXYZ.X + pColor->spec.CIEXYZ.Y + pColor->spec.CIEXYZ.Z) == 0.0) {
+	    div = EPS;
+	} 
+	xyY_return.x = pColor->spec.CIEXYZ.X / div;
+	xyY_return.y = pColor->spec.CIEXYZ.Y / div;
+	xyY_return.Y = pColor->spec.CIEXYZ.Y;
+
+	/* Copy result to pColor */
+	memcpy ((char *)&pColor->spec, (char *)&xyY_return, sizeof(XcmsCIExyY));
+
+	/* Identify that the format is now CIEXYZ */
+	pColor->format = XcmsCIExyYFormat;
+    }
+    return(XcmsSuccess);
+}