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-rw-r--r--libX11/src/xcms/Luv.c802
1 files changed, 401 insertions, 401 deletions
diff --git a/libX11/src/xcms/Luv.c b/libX11/src/xcms/Luv.c
index 82bc2946a..0b1325252 100644
--- a/libX11/src/xcms/Luv.c
+++ b/libX11/src/xcms/Luv.c
@@ -1,401 +1,401 @@
-
-/*
- * 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
- * CIELuv.c
- *
- * DESCRIPTION
- * This file contains routines that support the CIE L*u*v*
- * color space to include conversions to and from the CIE
- * XYZ space.
- *
- * DOCUMENTATION
- * "TekColor Color Management System, System Implementor's Manual"
- * and
- * Fred W. Billmeyer & Max Saltzman, "Principles of Color
- * Technology", John Wily & Sons, Inc, 1981.
- */
-
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-#include <X11/Xos.h>
-#include "Xlibint.h"
-#include "Xcmsint.h"
-#include "Cv.h"
-
-#include <stdio.h> /* sscanf */
-
-
-/*
- * FORWARD DECLARATIONS
- */
-
-static int CIELuv_ParseString(register char *spec, XcmsColor *pColor);
-static Status XcmsCIELuv_ValidSpec(XcmsColor *pColor);
-
-/*
- * DEFINES
- * Internal definitions that need NOT be exported to any package
- * or program using this package.
- */
-#ifdef DBL_EPSILON
-# define XMY_DBL_EPSILON DBL_EPSILON
-#else
-# define XMY_DBL_EPSILON 0.00001
-#endif
-
-
-/*
- * LOCAL VARIABLES
- */
-
- /*
- * NULL terminated list of functions applied to get from CIELuv to CIEXYZ
- */
-static XcmsConversionProc Fl_CIELuv_to_CIEXYZ[] = {
- XcmsCIELuvToCIEuvY,
- XcmsCIEuvYToCIEXYZ,
- NULL
-};
-
- /*
- * NULL terminated list of functions applied to get from CIEXYZ to CIELuv
- */
-static XcmsConversionProc Fl_CIEXYZ_to_CIELuv[] = {
- XcmsCIEXYZToCIEuvY,
- XcmsCIEuvYToCIELuv,
- NULL
-};
-
-/*
- * GLOBALS
- */
-
- /*
- * CIE Luv Color Space
- */
-XcmsColorSpace XcmsCIELuvColorSpace =
- {
- _XcmsCIELuv_prefix, /* prefix */
- XcmsCIELuvFormat, /* id */
- CIELuv_ParseString, /* parseString */
- Fl_CIELuv_to_CIEXYZ, /* to_CIEXYZ */
- Fl_CIEXYZ_to_CIELuv, /* from_CIEXYZ */
- 1
- };
-
-
-/************************************************************************
- * *
- * PRIVATE ROUTINES *
- * *
- ************************************************************************/
-
-/*
- * NAME
- * CIELuv_ParseString
- *
- * SYNOPSIS
- */
-static int
-CIELuv_ParseString(
- register char *spec,
- XcmsColor *pColor)
-/*
- * DESCRIPTION
- * This routines takes a string and attempts to convert
- * it into a XcmsColor structure with XcmsCIELuvFormat.
- * The assumed CIELuv string syntax is:
- * CIELuv:<L>/<u>/<v>
- * Where L, u, and v 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, _XcmsCIELuv_prefix, n) != 0) {
- return(XcmsFailure);
- }
-
- /*
- * Attempt to parse the value portion.
- */
- if (sscanf(spec + n + 1, "%lf/%lf/%lf",
- &pColor->spec.CIELuv.L_star,
- &pColor->spec.CIELuv.u_star,
- &pColor->spec.CIELuv.v_star) != 3) {
- char *s; /* Maybe failed due to locale */
- int f;
- if ((s = strdup(spec))) {
- for (f = 0; s[f]; ++f)
- if (s[f] == '.')
- s[f] = ',';
- else if (s[f] == ',')
- s[f] = '.';
- if (sscanf(s + n + 1, "%lf/%lf/%lf",
- &pColor->spec.CIELuv.L_star,
- &pColor->spec.CIELuv.u_star,
- &pColor->spec.CIELuv.v_star) != 3) {
- free(s);
- return(XcmsFailure);
- }
- free(s);
- } else
- return(XcmsFailure);
- }
- pColor->format = XcmsCIELuvFormat;
- pColor->pixel = 0;
- return(XcmsCIELuv_ValidSpec(pColor));
-}
-
-
-/************************************************************************
- * *
- * PUBLIC ROUTINES *
- * *
- ************************************************************************/
-
-/*
- * NAME
- * XcmsCIELuv_ValidSpec
- *
- * SYNOPSIS
- */
-static Status
-XcmsCIELuv_ValidSpec(
- XcmsColor *pColor)
-/*
- * DESCRIPTION
- * Checks if color specification valid for CIE L*u*v*.
- *
- * RETURNS
- * XcmsFailure if invalid,
- * XcmsSuccess if valid.
- *
- */
-{
- if (pColor->format != XcmsCIELuvFormat
- ||
- (pColor->spec.CIELuv.L_star < 0.0 - XMY_DBL_EPSILON)
- ||
- (pColor->spec.CIELuv.L_star > 100.0 + XMY_DBL_EPSILON)) {
- return(XcmsFailure);
- }
- return(XcmsSuccess);
-}
-
-
-/*
- * NAME
- * XcmsCIELuvToCIEuvY - convert CIELuv to CIEuvY
- *
- * SYNOPSIS
- */
-Status
-XcmsCIELuvToCIEuvY(
- XcmsCCC ccc,
- XcmsColor *pLuv_WhitePt,
- XcmsColor *pColors_in_out,
- unsigned int nColors)
-/*
- * DESCRIPTION
- * Converts color specifications in an array of XcmsColor
- * structures from CIELuv format to CIEuvY format.
- *
- * RETURNS
- * XcmsFailure if failed,
- * XcmsSuccess if succeeded.
- *
- */
-{
- XcmsColor *pColor = pColors_in_out;
- XcmsColor whitePt;
- XcmsCIEuvY uvY_return;
- XcmsFloat tmpVal;
- register int i;
-
- /*
- * Check arguments
- */
- if (pLuv_WhitePt == NULL || pColors_in_out == NULL) {
- return(XcmsFailure);
- }
-
- /*
- * Make sure white point is in CIEuvY form
- */
- if (pLuv_WhitePt->format != XcmsCIEuvYFormat) {
- /* Make copy of the white point because we're going to modify it */
- memcpy((char *)&whitePt, (char *)pLuv_WhitePt, sizeof(XcmsColor));
- if (!_XcmsDIConvertColors(ccc, &whitePt, (XcmsColor *)NULL,
- 1, XcmsCIEuvYFormat)) {
- return(XcmsFailure);
- }
- pLuv_WhitePt = &whitePt;
- }
- /* Make sure it is a white point, i.e., Y == 1.0 */
- if (pLuv_WhitePt->spec.CIEuvY.Y != 1.0) {
- return(XcmsFailure);
- }
-
- /*
- * Now convert each XcmsColor structure to CIEXYZ form
- */
- for (i = 0; i < nColors; i++, pColor++) {
-
- /* Make sure original format is CIELuv and is valid */
- if (!XcmsCIELuv_ValidSpec(pColor)) {
- return(XcmsFailure);
- }
-
- if (pColor->spec.CIELuv.L_star < 7.99953624) {
- uvY_return.Y = pColor->spec.CIELuv.L_star / 903.29;
- } else {
- tmpVal = (pColor->spec.CIELuv.L_star + 16.0) / 116.0;
- uvY_return.Y = tmpVal * tmpVal * tmpVal; /* tmpVal ** 3 */
- }
-
-
-
- if (pColor->spec.CIELuv.L_star == 0.0) {
- uvY_return.u_prime = pLuv_WhitePt->spec.CIEuvY.u_prime;
- uvY_return.v_prime = pLuv_WhitePt->spec.CIEuvY.v_prime;
- } else {
- tmpVal = 13.0 * (pColor->spec.CIELuv.L_star / 100.0);
- uvY_return.u_prime = pColor->spec.CIELuv.u_star/tmpVal +
- pLuv_WhitePt->spec.CIEuvY.u_prime;
- uvY_return.v_prime = pColor->spec.CIELuv.v_star/tmpVal +
- pLuv_WhitePt->spec.CIEuvY.v_prime;
- }
- /* Copy result to pColor */
- memcpy((char *)&pColor->spec, (char *)&uvY_return, sizeof(XcmsCIEuvY));
-
- /* Identify that the format is now CIEuvY */
- pColor->format = XcmsCIEuvYFormat;
- }
- return(XcmsSuccess);
-}
-
-
-/*
- * NAME
- * XcmsCIEuvYToCIELuv - convert CIEuvY to CIELuv
- *
- * SYNOPSIS
- */
-Status
-XcmsCIEuvYToCIELuv(
- XcmsCCC ccc,
- XcmsColor *pLuv_WhitePt,
- XcmsColor *pColors_in_out,
- unsigned int nColors)
-/*
- * DESCRIPTION
- * Converts color specifications in an array of XcmsColor
- * structures from CIEuvY format to CIELab format.
- *
- * RETURNS
- * XcmsFailure if failed,
- * XcmsSuccess if succeeded.
- *
- */
-{
- XcmsColor *pColor = pColors_in_out;
- XcmsColor whitePt;
- XcmsCIELuv Luv_return;
- XcmsFloat tmpVal;
- register int i;
-
- /*
- * Check arguments
- */
- if (pLuv_WhitePt == NULL || pColors_in_out == NULL) {
- return(XcmsFailure);
- }
-
- /*
- * Make sure white point is in CIEuvY form
- */
- if (pLuv_WhitePt->format != XcmsCIEuvYFormat) {
- /* Make copy of the white point because we're going to modify it */
- memcpy((char *)&whitePt, (char *)pLuv_WhitePt, sizeof(XcmsColor));
- if (!_XcmsDIConvertColors(ccc, &whitePt,
- (XcmsColor *)NULL, 1, XcmsCIEuvYFormat)) {
- return(XcmsFailure);
- }
- pLuv_WhitePt = &whitePt;
- }
- /* Make sure it is a white point, i.e., Y == 1.0 */
- if (pLuv_WhitePt->spec.CIEuvY.Y != 1.0) {
- return(XcmsFailure);
- }
-
- /*
- * Now convert each XcmsColor structure to CIEXYZ form
- */
- for (i = 0; i < nColors; i++, pColor++) {
-
- if (!_XcmsCIEuvY_ValidSpec(pColor)) {
- return(XcmsFailure);
- }
-
- /* Now convert the uvY to Luv */
- Luv_return.L_star =
- (pColor->spec.CIEuvY.Y < 0.008856)
- ?
- (pColor->spec.CIEuvY.Y * 903.29)
- :
- ((XcmsFloat)(XCMS_CUBEROOT(pColor->spec.CIEuvY.Y) * 116.0) - 16.0);
- tmpVal = 13.0 * (Luv_return.L_star / 100.0);
- Luv_return.u_star = tmpVal *
- (pColor->spec.CIEuvY.u_prime - pLuv_WhitePt->spec.CIEuvY.u_prime);
- Luv_return.v_star = tmpVal *
- (pColor->spec.CIEuvY.v_prime - pLuv_WhitePt->spec.CIEuvY.v_prime);
-
- /* Copy result to pColor */
- memcpy((char *)&pColor->spec, (char *)&Luv_return, sizeof(XcmsCIELuv));
-
- /* Identify that the format is now CIEuvY */
- pColor->format = XcmsCIELuvFormat;
- }
- return(XcmsSuccess);
-}
+
+/*
+ * 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
+ * CIELuv.c
+ *
+ * DESCRIPTION
+ * This file contains routines that support the CIE L*u*v*
+ * color space to include conversions to and from the CIE
+ * XYZ space.
+ *
+ * DOCUMENTATION
+ * "TekColor Color Management System, System Implementor's Manual"
+ * and
+ * Fred W. Billmeyer & Max Saltzman, "Principles of Color
+ * Technology", John Wily & Sons, Inc, 1981.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include <X11/Xos.h>
+#include "Xlibint.h"
+#include "Xcmsint.h"
+#include "Cv.h"
+
+#include <stdio.h> /* sscanf */
+
+
+/*
+ * FORWARD DECLARATIONS
+ */
+
+static int CIELuv_ParseString(register char *spec, XcmsColor *pColor);
+static Status XcmsCIELuv_ValidSpec(XcmsColor *pColor);
+
+/*
+ * DEFINES
+ * Internal definitions that need NOT be exported to any package
+ * or program using this package.
+ */
+#ifdef DBL_EPSILON
+# define XMY_DBL_EPSILON DBL_EPSILON
+#else
+# define XMY_DBL_EPSILON 0.00001
+#endif
+
+
+/*
+ * LOCAL VARIABLES
+ */
+
+ /*
+ * NULL terminated list of functions applied to get from CIELuv to CIEXYZ
+ */
+static XcmsConversionProc Fl_CIELuv_to_CIEXYZ[] = {
+ XcmsCIELuvToCIEuvY,
+ XcmsCIEuvYToCIEXYZ,
+ NULL
+};
+
+ /*
+ * NULL terminated list of functions applied to get from CIEXYZ to CIELuv
+ */
+static XcmsConversionProc Fl_CIEXYZ_to_CIELuv[] = {
+ XcmsCIEXYZToCIEuvY,
+ XcmsCIEuvYToCIELuv,
+ NULL
+};
+
+/*
+ * GLOBALS
+ */
+
+ /*
+ * CIE Luv Color Space
+ */
+XcmsColorSpace XcmsCIELuvColorSpace =
+ {
+ _XcmsCIELuv_prefix, /* prefix */
+ XcmsCIELuvFormat, /* id */
+ CIELuv_ParseString, /* parseString */
+ Fl_CIELuv_to_CIEXYZ, /* to_CIEXYZ */
+ Fl_CIEXYZ_to_CIELuv, /* from_CIEXYZ */
+ 1
+ };
+
+
+/************************************************************************
+ * *
+ * PRIVATE ROUTINES *
+ * *
+ ************************************************************************/
+
+/*
+ * NAME
+ * CIELuv_ParseString
+ *
+ * SYNOPSIS
+ */
+static int
+CIELuv_ParseString(
+ register char *spec,
+ XcmsColor *pColor)
+/*
+ * DESCRIPTION
+ * This routines takes a string and attempts to convert
+ * it into a XcmsColor structure with XcmsCIELuvFormat.
+ * The assumed CIELuv string syntax is:
+ * CIELuv:<L>/<u>/<v>
+ * Where L, u, and v 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, _XcmsCIELuv_prefix, n) != 0) {
+ return(XcmsFailure);
+ }
+
+ /*
+ * Attempt to parse the value portion.
+ */
+ if (sscanf(spec + n + 1, "%lf/%lf/%lf",
+ &pColor->spec.CIELuv.L_star,
+ &pColor->spec.CIELuv.u_star,
+ &pColor->spec.CIELuv.v_star) != 3) {
+ char *s; /* Maybe failed due to locale */
+ int f;
+ if ((s = strdup(spec))) {
+ for (f = 0; s[f]; ++f)
+ if (s[f] == '.')
+ s[f] = ',';
+ else if (s[f] == ',')
+ s[f] = '.';
+ if (sscanf(s + n + 1, "%lf/%lf/%lf",
+ &pColor->spec.CIELuv.L_star,
+ &pColor->spec.CIELuv.u_star,
+ &pColor->spec.CIELuv.v_star) != 3) {
+ free(s);
+ return(XcmsFailure);
+ }
+ free(s);
+ } else
+ return(XcmsFailure);
+ }
+ pColor->format = XcmsCIELuvFormat;
+ pColor->pixel = 0;
+ return(XcmsCIELuv_ValidSpec(pColor));
+}
+
+
+/************************************************************************
+ * *
+ * PUBLIC ROUTINES *
+ * *
+ ************************************************************************/
+
+/*
+ * NAME
+ * XcmsCIELuv_ValidSpec
+ *
+ * SYNOPSIS
+ */
+static Status
+XcmsCIELuv_ValidSpec(
+ XcmsColor *pColor)
+/*
+ * DESCRIPTION
+ * Checks if color specification valid for CIE L*u*v*.
+ *
+ * RETURNS
+ * XcmsFailure if invalid,
+ * XcmsSuccess if valid.
+ *
+ */
+{
+ if (pColor->format != XcmsCIELuvFormat
+ ||
+ (pColor->spec.CIELuv.L_star < 0.0 - XMY_DBL_EPSILON)
+ ||
+ (pColor->spec.CIELuv.L_star > 100.0 + XMY_DBL_EPSILON)) {
+ return(XcmsFailure);
+ }
+ return(XcmsSuccess);
+}
+
+
+/*
+ * NAME
+ * XcmsCIELuvToCIEuvY - convert CIELuv to CIEuvY
+ *
+ * SYNOPSIS
+ */
+Status
+XcmsCIELuvToCIEuvY(
+ XcmsCCC ccc,
+ XcmsColor *pLuv_WhitePt,
+ XcmsColor *pColors_in_out,
+ unsigned int nColors)
+/*
+ * DESCRIPTION
+ * Converts color specifications in an array of XcmsColor
+ * structures from CIELuv format to CIEuvY format.
+ *
+ * RETURNS
+ * XcmsFailure if failed,
+ * XcmsSuccess if succeeded.
+ *
+ */
+{
+ XcmsColor *pColor = pColors_in_out;
+ XcmsColor whitePt;
+ XcmsCIEuvY uvY_return;
+ XcmsFloat tmpVal;
+ register int i;
+
+ /*
+ * Check arguments
+ */
+ if (pLuv_WhitePt == NULL || pColors_in_out == NULL) {
+ return(XcmsFailure);
+ }
+
+ /*
+ * Make sure white point is in CIEuvY form
+ */
+ if (pLuv_WhitePt->format != XcmsCIEuvYFormat) {
+ /* Make copy of the white point because we're going to modify it */
+ memcpy((char *)&whitePt, (char *)pLuv_WhitePt, sizeof(XcmsColor));
+ if (!_XcmsDIConvertColors(ccc, &whitePt, (XcmsColor *)NULL,
+ 1, XcmsCIEuvYFormat)) {
+ return(XcmsFailure);
+ }
+ pLuv_WhitePt = &whitePt;
+ }
+ /* Make sure it is a white point, i.e., Y == 1.0 */
+ if (pLuv_WhitePt->spec.CIEuvY.Y != 1.0) {
+ return(XcmsFailure);
+ }
+
+ /*
+ * Now convert each XcmsColor structure to CIEXYZ form
+ */
+ for (i = 0; i < nColors; i++, pColor++) {
+
+ /* Make sure original format is CIELuv and is valid */
+ if (!XcmsCIELuv_ValidSpec(pColor)) {
+ return(XcmsFailure);
+ }
+
+ if (pColor->spec.CIELuv.L_star < 7.99953624) {
+ uvY_return.Y = pColor->spec.CIELuv.L_star / 903.29;
+ } else {
+ tmpVal = (pColor->spec.CIELuv.L_star + 16.0) / 116.0;
+ uvY_return.Y = tmpVal * tmpVal * tmpVal; /* tmpVal ** 3 */
+ }
+
+
+
+ if (pColor->spec.CIELuv.L_star == 0.0) {
+ uvY_return.u_prime = pLuv_WhitePt->spec.CIEuvY.u_prime;
+ uvY_return.v_prime = pLuv_WhitePt->spec.CIEuvY.v_prime;
+ } else {
+ tmpVal = 13.0 * (pColor->spec.CIELuv.L_star / 100.0);
+ uvY_return.u_prime = pColor->spec.CIELuv.u_star/tmpVal +
+ pLuv_WhitePt->spec.CIEuvY.u_prime;
+ uvY_return.v_prime = pColor->spec.CIELuv.v_star/tmpVal +
+ pLuv_WhitePt->spec.CIEuvY.v_prime;
+ }
+ /* Copy result to pColor */
+ memcpy((char *)&pColor->spec, (char *)&uvY_return, sizeof(XcmsCIEuvY));
+
+ /* Identify that the format is now CIEuvY */
+ pColor->format = XcmsCIEuvYFormat;
+ }
+ return(XcmsSuccess);
+}
+
+
+/*
+ * NAME
+ * XcmsCIEuvYToCIELuv - convert CIEuvY to CIELuv
+ *
+ * SYNOPSIS
+ */
+Status
+XcmsCIEuvYToCIELuv(
+ XcmsCCC ccc,
+ XcmsColor *pLuv_WhitePt,
+ XcmsColor *pColors_in_out,
+ unsigned int nColors)
+/*
+ * DESCRIPTION
+ * Converts color specifications in an array of XcmsColor
+ * structures from CIEuvY format to CIELab format.
+ *
+ * RETURNS
+ * XcmsFailure if failed,
+ * XcmsSuccess if succeeded.
+ *
+ */
+{
+ XcmsColor *pColor = pColors_in_out;
+ XcmsColor whitePt;
+ XcmsCIELuv Luv_return;
+ XcmsFloat tmpVal;
+ register int i;
+
+ /*
+ * Check arguments
+ */
+ if (pLuv_WhitePt == NULL || pColors_in_out == NULL) {
+ return(XcmsFailure);
+ }
+
+ /*
+ * Make sure white point is in CIEuvY form
+ */
+ if (pLuv_WhitePt->format != XcmsCIEuvYFormat) {
+ /* Make copy of the white point because we're going to modify it */
+ memcpy((char *)&whitePt, (char *)pLuv_WhitePt, sizeof(XcmsColor));
+ if (!_XcmsDIConvertColors(ccc, &whitePt,
+ (XcmsColor *)NULL, 1, XcmsCIEuvYFormat)) {
+ return(XcmsFailure);
+ }
+ pLuv_WhitePt = &whitePt;
+ }
+ /* Make sure it is a white point, i.e., Y == 1.0 */
+ if (pLuv_WhitePt->spec.CIEuvY.Y != 1.0) {
+ return(XcmsFailure);
+ }
+
+ /*
+ * Now convert each XcmsColor structure to CIEXYZ form
+ */
+ for (i = 0; i < nColors; i++, pColor++) {
+
+ if (!_XcmsCIEuvY_ValidSpec(pColor)) {
+ return(XcmsFailure);
+ }
+
+ /* Now convert the uvY to Luv */
+ Luv_return.L_star =
+ (pColor->spec.CIEuvY.Y < 0.008856)
+ ?
+ (pColor->spec.CIEuvY.Y * 903.29)
+ :
+ ((XcmsFloat)(XCMS_CUBEROOT(pColor->spec.CIEuvY.Y) * 116.0) - 16.0);
+ tmpVal = 13.0 * (Luv_return.L_star / 100.0);
+ Luv_return.u_star = tmpVal *
+ (pColor->spec.CIEuvY.u_prime - pLuv_WhitePt->spec.CIEuvY.u_prime);
+ Luv_return.v_star = tmpVal *
+ (pColor->spec.CIEuvY.v_prime - pLuv_WhitePt->spec.CIEuvY.v_prime);
+
+ /* Copy result to pColor */
+ memcpy((char *)&pColor->spec, (char *)&Luv_return, sizeof(XcmsCIELuv));
+
+ /* Identify that the format is now CIEuvY */
+ pColor->format = XcmsCIELuvFormat;
+ }
+ return(XcmsSuccess);
+}