ephemerisUtil.h

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/*******************************************************************************
** Copyright (c) 2014 MAK Technologies, Inc.
** All rights reserved.
*******************************************************************************/

#pragma once

#include "vrfutil/vrfutilDefines.h"
#include <time.h>
#include <matrix/vlMath.h>

/***************************************************************************/
/* Note: year,month,date = calendar date, 1801-2099 only.             */
/*       Eastern longitude positive, Western longitude negative       */
/*       Northern latitude positive, Southern latitude negative       */
/*       The longitude value IS critical in this function!            */
/*       altit = the altitude which the Sun should cross              */
/*               Set to -35/60 degrees for rise/set, -6 degrees       */
/*               for civil, -12 degrees for nautical and -18          */
/*               degrees for astronomical twilight.                   */
/*        *rise = where to store the rise time                        */
/*        *set  = where to store the set  time                        */
/*                Both times are relative to the specified altitude,  */
/*                and thus this function can be used to compute       */
/*                various twilight times, as well as rise/set times   */
/* Return value:  0 = sun rises/sets this day, times stored at        */
/*                    *trise and *tset.                               */
/*               +1 = sun above the specified "horizon" 24 hours.     */
/*                    *trise set to time when the sun is at south,    */
/*                    minus 12 hours while *tset is set to the south  */
/*                    time plus 12 hours. "Day" length = 24 hours     */
/*               -1 = sun is below the specified "horizon" 24 hours   */
/*                    "Day" length = 0 hours, *trise and *tset are    */
/*                    both set to the time when the sun is at south.  */
/*                                                                    */
/**********************************************************************/
DT_DLL_vrfutil bool sunriseset( time_t utcTime, double lon, double lat,
                  double altit, double& trise, double& tset );

DT_DLL_vrfutil void find_moonrise_set(time_t utcTime, double glong, double glat,
   double& moonrise, double& moonset);

DT_DLL_vrfutil double moonIllumination(time_t utcTime);

DT_DLL_vrfutil time_t timezone_adjusted(time_t utcTime, double glong);