diff options
Diffstat (limited to 'nx-X11/lib/src/xcms/Luv.c')
-rw-r--r-- | nx-X11/lib/src/xcms/Luv.c | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/nx-X11/lib/src/xcms/Luv.c b/nx-X11/lib/src/xcms/Luv.c new file mode 100644 index 000000000..2bce977ea --- /dev/null +++ b/nx-X11/lib/src/xcms/Luv.c @@ -0,0 +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 <nx-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; + unsigned 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; + unsigned 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); +} |