Add:Core:Support for automatic day night switching|Thanks chollya

git-svn-id: http://svn.code.sf.net/p/navit/code/trunk/navit@2746 ffa7fe5e-494d-0410-b361-a75ebd5db220

9 files changed, 552 insertions, 5 deletions

diff --git a/navit/Makefile.am b/navit/Makefile.am
index 1797d2783..56ae0eb98 100644
--- a/navit/Makefile.am
+++ b/navit/Makefile.am
@@ -41,7 +41,7 @@ libnavit_la_SOURCES = announcement.c atom.c attr.c cache.c callback.c command.c
 	map_data.h mapset.h maptype.h menu.h messages.h navigation.h navit.h osd.h \
 	param.h phrase.h plugin.h point.h plugin_def.h projection.h popup.h route.h profile.h roadprofile.h search.h speech.h start_real.h \
 	transform.h track.h util.h vehicle.h vehicleprofile.h window.h xmlconfig.h zipfile.h \
-	navit_nls.h
+	navit_nls.h sunriset.c sunriset.h
 
 comma=,
 XSLTS=@XSLTS@
diff --git a/navit/attr_def.h b/navit/attr_def.h
index 20f3322ef..77ca1d703 100644
--- a/navit/attr_def.h
+++ b/navit/attr_def.h
@@ -259,6 +259,8 @@ ATTR(street_name_match)
 ATTR(language)
 ATTR(subtype)
 ATTR(filter)
+ATTR(daylayout)
+ATTR(nightlayout)
 ATTR2(0x0003ffff,type_string_end)
 ATTR2(0x00040000,type_special_begin)
 ATTR(order)
diff --git a/navit/layout.c b/navit/layout.c
index 230fa354a..332a9f526 100644
--- a/navit/layout.c
+++ b/navit/layout.c
@@ -30,7 +30,7 @@ struct layout * layout_new(struct attr *parent, struct attr **attrs)
 {
 	struct layout *l;
 	struct color def_color = {0xffff, 0xefef, 0xb7b7, 0xffff};
-	struct attr *name_attr,*color_attr,*order_delta_attr,*font_attr;
+	struct attr *name_attr,*color_attr,*order_delta_attr,*font_attr,*day_attr,*night_attr;
 
 	if (! (name_attr=attr_search(attrs, NULL, attr_name)))
 		return NULL;
@@ -39,6 +39,12 @@ struct layout * layout_new(struct attr *parent, struct attr **attrs)
 	if ((font_attr=attr_search(attrs, NULL, attr_font))) {
 		l->font = g_strdup(font_attr->u.str);
 	}
+	if ((day_attr=attr_search(attrs, NULL, attr_daylayout))) {
+		l->dayname = g_strdup(day_attr->u.str);
+	}
+	if ((night_attr=attr_search(attrs, NULL, attr_nightlayout))) {
+		l->nightname = g_strdup(night_attr->u.str);
+	}
 	if ((color_attr=attr_search(attrs, NULL, attr_color)))
 		l->color = *color_attr->u.color;
 	else
diff --git a/navit/layout.h b/navit/layout.h
index 1b2f1c09d..ef5fd1062 100644
--- a/navit/layout.h
+++ b/navit/layout.h
@@ -71,7 +71,7 @@ struct cursor {
 	int interval;
 };
 
-struct layout { char *name; char *font; struct color color; GList *layers; GList *cursors; int order_delta; };
+struct layout { char *name; char* dayname; char* nightname; char *font; struct color color; GList *layers; GList *cursors; int order_delta; };
 
 /* prototypes */
 struct layout *layout_new(struct attr *parent, struct attr **attrs);
diff --git a/navit/navit.c b/navit/navit.c
index 89ae60478..03c8059c6 100644
--- a/navit/navit.c
+++ b/navit/navit.c
@@ -60,6 +60,7 @@
 #include "util.h"
 #include "messages.h"
 #include "vehicleprofile.h"
+#include "sunriset.h"
 
 /**
  * @defgroup navit the navit core instance. navit is the object containing nearly everything: A set of maps, one or more vehicle, a graphics object for rendering the map, a gui object for displaying the user interface, a route object, a navigation object and so on. Be warned that it is theoretically possible to have more than one navit object
@@ -134,6 +135,7 @@ struct navit {
 	GList *vehicleprofiles;
 	int pitch;
 	int follow_cursor;
+	int prevTs;
 };
 
 struct gui *main_loop_gui;
@@ -660,6 +662,8 @@ navit_new(struct attr *parent, struct attr **attrs)
 	center.x=co.x;
 	center.y=co.y;
 	center.pro = pro;
+	
+	this_->prevTs=0;
 
 	transform_setup(this_->trans, &center, zoom, (this_->orientation != -1) ? this_->orientation : 0);
 	for (;*attrs; attrs++) {
@@ -2075,6 +2079,7 @@ navit_vehicle_update(struct navit *this_, struct navit_vehicle *nv)
 		profile(0,"return 1\n");
 		return;
 	}
+	navit_layout_switch(this_);
 	if (this_->vehicle == nv && this_->tracking_flag)
 		tracking=this_->tracking;
 	if (tracking) {
@@ -2252,6 +2257,114 @@ navit_get_displaylist(struct navit *this_)
 	return this_->displaylist;
 }
 
+void
+navit_layout_switch(struct navit *n) 
+{
+
+    int currTs=0;
+    struct attr iso8601_attr,geo_attr,layout_attr;
+    double trise,tset,trise_actual;
+    struct layout *l;
+    
+    if (navit_get_attr(n,attr_layout,&layout_attr,NULL)!=1) {
+	return; //No layout - nothing to switch
+    }
+    l=layout_attr.u.layout;
+    
+    if (l->dayname || l->nightname) {
+	//Ok, we know that we have profile to switch
+	
+	//Check that we aren't calculating too fast
+	if (vehicle_get_attr(n->vehicle->vehicle, attr_position_time_iso8601,&iso8601_attr,NULL)==1) {
+		currTs=iso8601_to_secs(iso8601_attr.u.str);
+	}
+	if (currTs-(n->prevTs)<60) {
+	    //We've have to wait a little
+	    return;
+	}
+	
+	if (vehicle_get_attr(n->vehicle->vehicle, attr_position_coord_geo,&geo_attr,NULL)!=1) {
+		//No position - no sun
+		return;
+	}
+	if (vehicle_get_attr(n->vehicle->vehicle, attr_position_valid, &geo_attr,NULL) && geo_attr.u.num==attr_position_valid_invalid) {
+		return; //No valid fix yet
+	}
+	
+	//We calculate sunrise anyway, cause it is need both for day and for night
+        if (__sunriset__(currTs,geo_attr.u.coord_geo->lat,geo_attr.u.coord_geo->lng,35,1,&trise,&tset)!=0) {
+		//near the pole sun never rises/sets, so we should never switch profiles
+		n->prevTs=currTs;
+		return;
+	    }
+	
+        trise_actual=trise;
+	
+	if (l->dayname) {
+	
+	    if ((HOURS(trise)*60+MINUTES(trise)==(currTs%86400)/60) || 
+		    (n->prevTs==0 && ((HOURS(trise)*60+MINUTES(trise)<(currTs%86400)/60)))) {
+		//The sun is rising now!
+		if (strcmp(l->name,l->dayname)) {
+		    navit_set_layout_by_name(n,l->dayname);
+		}
+	    }
+	}
+	if (l->nightname) {
+	    if (__sunriset__(currTs,geo_attr.u.coord_geo->lat,geo_attr.u.coord_geo->lng,-12,0,&trise,&tset)!=0) {
+		//near the pole sun never rises/sets, so we should never switch profiles
+		n->prevTs=currTs;
+		return;
+	    }
+	    
+	    if (HOURS(tset)*60+MINUTES(tset)==((currTs%86400)/60)
+		|| (n->prevTs==0 && (((HOURS(tset)*60+MINUTES(tset)<(currTs%86400)/60)) || 
+			((HOURS(trise_actual)*60+MINUTES(trise_actual)>(currTs%86400)/60))))) {
+		//Time to sleep
+		if (strcmp(l->name,l->nightname)) {
+		    navit_set_layout_by_name(n,l->nightname);
+		}
+	    }	
+	}
+	
+	n->prevTs=currTs;
+    }
+}
+
+int 
+navit_set_layout_by_name(struct navit *n,char *name) 
+{
+    struct layout *l;
+    struct attr_iter iter;
+    struct attr layout_attr;
+
+    iter.u.list=0x00;
+
+    if (navit_get_attr(n,attr_layout,&layout_attr,&iter)!=1) {
+	return 0; //No layouts - nothing to do
+    }
+    if (iter.u.list==NULL) {
+	return 0;
+    }
+    
+    iter.u.list=g_list_first(iter.u.list);
+    
+    while(iter.u.list) {
+	l=(struct layout*)iter.u.list->data;
+	if (!strcmp(name,l->name)) {
+	    layout_attr.u.layout=l;
+	    layout_attr.type=attr_layout;
+	    navit_set_attr(n,&layout_attr);
+	    iter.u.list=g_list_first(iter.u.list);
+	    return 1;
+	}
+	iter.u.list=g_list_next(iter.u.list);
+    }
+
+    iter.u.list=g_list_first(iter.u.list);
+    return 0;
+}
+
 int
 navit_block(struct navit *this_, int block)
 {
diff --git a/navit/navit.h b/navit/navit.h
index 5f71c62c6..8745889f3 100644
--- a/navit/navit.h
+++ b/navit/navit.h
@@ -97,6 +97,8 @@ struct route *navit_get_route(struct navit *this_);
 struct navigation *navit_get_navigation(struct navit *this_);
 struct displaylist *navit_get_displaylist(struct navit *this_);
 int navit_block(struct navit *this_, int block);
+void navit_layout_switch(struct navit *n);
+int navit_set_layout_by_name(struct navit *n, char* name);
 void navit_destroy(struct navit *this_);
 /* end of prototypes */
 #ifdef __cplusplus
diff --git a/navit/navit_shipped.xml b/navit/navit_shipped.xml
index efcf02b05..463f54e5b 100644
--- a/navit/navit_shipped.xml
+++ b/navit/navit_shipped.xml
@@ -340,7 +340,7 @@
             <map type="garmin" enabled="yes" data="/path/to/img" debug="4"/>
         </mapset>
 
-        <layout name="Car" color="#ffefb7" font="Liberation Sans">
+        <layout name="Car" nightlayout="Car-dark" color="#ffefb7" font="Liberation Sans">
 
             <cursor w="26" h="26">
                 <itemgra>
@@ -1945,7 +1945,7 @@
             </layer>
         </layout>
 
-        <layout name="Car-dark" color="#011001">
+        <layout name="Car-dark" daylayout="Car" color="#011001">
 
             <cursor w="26" h="26">
                 <itemgra>
diff --git a/navit/sunriset.c b/navit/sunriset.c
new file mode 100644
index 000000000..ee6a37b31
--- /dev/null
+++ b/navit/sunriset.c
@@ -0,0 +1,309 @@
+/*
+
+SUNRISET.C - computes Sun rise/set times, start/end of twilight, and
+             the length of the day at any date and latitude
+
+Written as DAYLEN.C, 1989-08-16
+
+Modified to SUNRISET.C, 1992-12-01
+
+(c) Paul Schlyter, 1989, 1992
+
+Released to the public domain by Paul Schlyter, December 1992
+
+*/
+
+
+#include <stdio.h>
+#include <math.h>
+#include <time.h>
+
+#include "sunriset.h"
+
+/* The "workhorse" function for sun rise/set times */
+
+int __sunriset__( time_t ts, double lon, double lat,
+                  double altit, int upper_limb, double *trise, double *tset )
+/***************************************************************************/
+/* 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.                   */
+/*         upper_limb: non-zero -> upper limb, zero -> center         */
+/*               Set to non-zero (e.g. 1) when computing rise/set     */
+/*               times, and to zero when computing start/end of       */
+/*               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 comupte       */
+/*                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.  */
+/*                                                                    */
+/**********************************************************************/
+{
+      int year, month, day;
+      struct tm ymd;
+      double  d,  /* Days since 2000 Jan 0.0 (negative before) */
+      sr,         /* Solar distance, astronomical units */
+      sRA,        /* Sun's Right Ascension */
+      sdec,       /* Sun's declination */
+      sradius,    /* Sun's apparent radius */
+      t,          /* Diurnal arc */
+      tsouth,     /* Time when Sun is at south */
+      sidtime;    /* Local sidereal time */
+
+      int rc = 0; /* Return cde from function - usually 0 */
+
+      //Split ts to y/m/d
+      gmtime_r(&ts,&ymd);
+      year=ymd.tm_year+1900;
+      month=ymd.tm_mon+1;
+      day=ymd.tm_mday+1;
+
+      /* Compute d of 12h local mean solar time */
+      d = days_since_2000_Jan_0(year,month,day) + 0.5 - lon/360.0;
+
+      /* Compute local sideral time of this moment */
+      sidtime = revolution( GMST0(d) + 180.0 + lon );
+
+      /* Compute Sun's RA + Decl at this moment */
+      sun_RA_dec( d, &sRA, &sdec, &sr );
+
+      /* Compute time when Sun is at south - in hours UT */
+      tsouth = 12.0 - rev180(sidtime - sRA)/15.0;
+
+      /* Compute the Sun's apparent radius, degrees */
+      sradius = 0.2666 / sr;
+
+      /* Do correction to upper limb, if necessary */
+      if ( upper_limb )
+            altit -= sradius;
+
+      /* Compute the diurnal arc that the Sun traverses to reach */
+      /* the specified altitide altit: */
+      {
+            double cost;
+            cost = ( sind(altit) - sind(lat) * sind(sdec) ) /
+                  ( cosd(lat) * cosd(sdec) );
+            if ( cost >= 1.0 )
+                  rc = -1, t = 0.0;       /* Sun always below altit */
+            else if ( cost <= -1.0 )
+                  rc = +1, t = 12.0;      /* Sun always above altit */
+            else
+                  t = acosd(cost)/15.0;   /* The diurnal arc, hours */
+      }
+
+      /* Store rise and set times - in hours UT */
+      *trise = tsouth - t;
+      *tset  = tsouth + t;
+
+      return rc;
+}  /* __sunriset__ */
+
+
+
+/* The "workhorse" function */
+
+
+double __daylen__( int year, int month, int day, double lon, double lat,
+                   double altit, int upper_limb )
+/**********************************************************************/
+/* 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 not critical. Set it to the correct   */
+/*       longitude if you're picky, otherwise set to to, say, 0.0     */
+/*       The latitude however IS critical - be sure to get it correct */
+/*       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.                   */
+/*         upper_limb: non-zero -> upper limb, zero -> center         */
+/*               Set to non-zero (e.g. 1) when computing day length   */
+/*               and to zero when computing day+twilight length.      */
+/**********************************************************************/
+{
+      double  d,  /* Days since 2000 Jan 0.0 (negative before) */
+      obl_ecl,    /* Obliquity (inclination) of Earth's axis */
+      sr,         /* Solar distance, astronomical units */
+      slon,       /* True solar longitude */
+      sin_sdecl,  /* Sine of Sun's declination */
+      cos_sdecl,  /* Cosine of Sun's declination */
+      sradius,    /* Sun's apparent radius */
+      t;          /* Diurnal arc */
+
+      /* Compute d of 12h local mean solar time */
+      d = days_since_2000_Jan_0(year,month,day) + 0.5 - lon/360.0;
+
+      /* Compute obliquity of ecliptic (inclination of Earth's axis) */
+      obl_ecl = 23.4393 - 3.563E-7 * d;
+
+      /* Compute Sun's position */
+      sunpos( d, &slon, &sr );
+
+      /* Compute sine and cosine of Sun's declination */
+      sin_sdecl = sind(obl_ecl) * sind(slon);
+      cos_sdecl = sqrt( 1.0 - sin_sdecl * sin_sdecl );
+
+      /* Compute the Sun's apparent radius, degrees */
+      sradius = 0.2666 / sr;
+
+      /* Do correction to upper limb, if necessary */
+      if ( upper_limb )
+            altit -= sradius;
+
+      /* Compute the diurnal arc that the Sun traverses to reach */
+      /* the specified altitide altit: */
+      {
+            double cost;
+            cost = ( sind(altit) - sind(lat) * sin_sdecl ) /
+                  ( cosd(lat) * cos_sdecl );
+            if ( cost >= 1.0 )
+                  t = 0.0;                      /* Sun always below altit */
+            else if ( cost <= -1.0 )
+                  t = 24.0;                     /* Sun always above altit */
+            else  t = (2.0/15.0) * acosd(cost); /* The diurnal arc, hours */
+      }
+      return t;
+}  /* __daylen__ */
+
+
+/* This function computes the Sun's position at any instant */
+
+void sunpos( double d, double *lon, double *r )
+/******************************************************/
+/* Computes the Sun's ecliptic longitude and distance */
+/* at an instant given in d, number of days since     */
+/* 2000 Jan 0.0.  The Sun's ecliptic latitude is not  */
+/* computed, since it's always very near 0.           */
+/******************************************************/
+{
+      double M,         /* Mean anomaly of the Sun */
+             w,         /* Mean longitude of perihelion */
+                        /* Note: Sun's mean longitude = M + w */
+             e,         /* Eccentricity of Earth's orbit */
+             E,         /* Eccentric anomaly */
+             x, y,      /* x, y coordinates in orbit */
+             v;         /* True anomaly */
+
+      /* Compute mean elements */
+      M = revolution( 356.0470 + 0.9856002585 * d );
+      w = 282.9404 + 4.70935E-5 * d;
+      e = 0.016709 - 1.151E-9 * d;
+
+      /* Compute true longitude and radius vector */
+      E = M + e * RADEG * sind(M) * ( 1.0 + e * cosd(M) );
+      x = cosd(E) - e;
+      y = sqrt( 1.0 - e*e ) * sind(E);
+      *r = sqrt( x*x + y*y );              /* Solar distance */
+      v = atan2d( y, x );                  /* True anomaly */
+      *lon = v + w;                        /* True solar longitude */
+      if ( *lon >= 360.0 )
+            *lon -= 360.0;                   /* Make it 0..360 degrees */
+}
+
+void sun_RA_dec( double d, double *RA, double *dec, double *r )
+{
+  double lon, obl_ecl;
+  double xs, ys, zs;
+  double xe, ye, ze;
+  
+  /* Compute Sun's ecliptical coordinates */
+  sunpos( d, &lon, r );
+  
+  /* Compute ecliptic rectangular coordinates */
+  xs = *r * cosd(lon);
+  ys = *r * sind(lon);
+  zs = 0; /* because the Sun is always in the ecliptic plane! */
+
+  /* Compute obliquity of ecliptic (inclination of Earth's axis) */
+  obl_ecl = 23.4393 - 3.563E-7 * d;
+  
+  /* Convert to equatorial rectangular coordinates - x is unchanged */
+  xe = xs;
+  ye = ys * cosd(obl_ecl);
+  ze = ys * sind(obl_ecl);
+  
+  /* Convert to spherical coordinates */
+  *RA = atan2d( ye, xe );
+  *dec = atan2d( ze, sqrt(xe*xe + ye*ye) );
+      
+}  /* sun_RA_dec */
+
+
+/******************************************************************/
+/* This function reduces any angle to within the first revolution */
+/* by subtracting or adding even multiples of 360.0 until the     */
+/* result is >= 0.0 and < 360.0                                   */
+/******************************************************************/
+
+#define INV360    ( 1.0 / 360.0 )
+
+double revolution( double x )
+/*****************************************/
+/* Reduce angle to within 0..360 degrees */
+/*****************************************/
+{
+      return( x - 360.0 * floor( x * INV360 ) );
+}  /* revolution */
+
+double rev180( double x )
+/*********************************************/
+/* Reduce angle to within -180..+180 degrees */
+/*********************************************/
+{
+      return( x - 360.0 * floor( x * INV360 + 0.5 ) );
+}  /* revolution */
+
+
+/*******************************************************************/
+/* This function computes GMST0, the Greenwhich Mean Sidereal Time */
+/* at 0h UT (i.e. the sidereal time at the Greenwhich meridian at  */
+/* 0h UT).  GMST is then the sidereal time at Greenwich at any     */
+/* time of the day.  I've generelized GMST0 as well, and define it */
+/* as:  GMST0 = GMST - UT  --  this allows GMST0 to be computed at */
+/* other times than 0h UT as well.  While this sounds somewhat     */
+/* contradictory, it is very practical:  instead of computing      */
+/* GMST like:                                                      */
+/*                                                                 */
+/*  GMST = (GMST0) + UT * (366.2422/365.2422)                      */
+/*                                                                 */
+/* where (GMST0) is the GMST last time UT was 0 hours, one simply  */
+/* computes:                                                       */
+/*                                                                 */
+/*  GMST = GMST0 + UT                                              */
+/*                                                                 */
+/* where GMST0 is the GMST "at 0h UT" but at the current moment!   */
+/* Defined in this way, GMST0 will increase with about 4 min a     */
+/* day.  It also happens that GMST0 (in degrees, 1 hr = 15 degr)   */
+/* is equal to the Sun's mean longitude plus/minus 180 degrees!    */
+/* (if we neglect aberration, which amounts to 20 seconds of arc   */
+/* or 1.33 seconds of time)                                        */
+/*                                                                 */
+/*******************************************************************/
+
+double GMST0( double d )
+{
+      double sidtim0;
+      /* Sidtime at 0h UT = L (Sun's mean longitude) + 180.0 degr  */
+      /* L = M + w, as defined in sunpos().  Since I'm too lazy to */
+      /* add these numbers, I'll let the C compiler do it for me.  */
+      /* Any decent C compiler will add the constants at compile   */
+      /* time, imposing no runtime or code overhead.               */
+      sidtim0 = revolution( ( 180.0 + 356.0470 + 282.9404 ) +
+                          ( 0.9856002585 + 4.70935E-5 ) * d );
+      return sidtim0;
+}  /* GMST0 */
diff --git a/navit/sunriset.h b/navit/sunriset.h
new file mode 100644
index 000000000..1ccad5797
--- /dev/null
+++ b/navit/sunriset.h
@@ -0,0 +1,115 @@
+extern const char* timezone_name;
+extern long int timezone_offset;
+
+#define TMOD(x) ((x)<0?(x)+24:((x)>=24?(x)-24:(x)))
+#define DAYSOFF(x) ((x)<0?"(-1) ":((x)>=24?"(+1) ":""))
+
+#define HOURS(h) ((int)(floor(h)))
+#define MINUTES(h) ((int)(60*(h-floor(h))))
+
+#define ABS(x) ((x)<0?-(x):(x))
+
+/* A macro to compute the number of days elapsed since 2000 Jan 0.0 */
+/* (which is equal to 1999 Dec 31, 0h UT)                           */
+/* Dan R sez: This is some pretty fucking high magic. */
+#define days_since_2000_Jan_0(y,m,d) \
+    (367L*(y)-((7*((y)+(((m)+9)/12)))/4)+((275*(m))/9)+(d)-730530L)
+
+/* Some conversion factors between radians and degrees */
+
+#ifndef PI
+ #define PI        3.1415926535897932384
+#endif
+
+#define RADEG     ( 180.0 / PI )
+#define DEGRAD    ( PI / 180.0 )
+
+/* The trigonometric functions in degrees */
+
+#define sind(x)  sin((x)*DEGRAD)
+#define cosd(x)  cos((x)*DEGRAD)
+#define tand(x)  tan((x)*DEGRAD)
+
+#define atand(x)    (RADEG*atan(x))
+#define asind(x)    (RADEG*asin(x))
+#define acosd(x)    (RADEG*acos(x))
+#define atan2d(y,x) (RADEG*atan2(y,x))
+
+/* Following are some macros around the "workhorse" function __daylen__ */
+/* They mainly fill in the desired values for the reference altitude    */
+/* below the horizon, and also selects whether this altitude should     */
+/* refer to the Sun's center or its upper limb.                         */
+
+
+/* This macro computes the length of the day, from sunrise to sunset. */
+/* Sunrise/set is considered to occur when the Sun's upper limb is    */
+/* 50 arc minutes below the horizon (this accounts for the refraction */
+/* of the Earth's atmosphere).                                        */
+/* The original version of the program used the value of 35 arc mins, */
+/* which is the accepted value in Sweden.                             */
+#define day_length(year,month,day,lon,lat)  \
+        __daylen__( year, month, day, lon, lat, -50.0/60.0, 1 )
+
+/* This macro computes the length of the day, including civil twilight. */
+/* Civil twilight starts/ends when the Sun's center is 6 degrees below  */
+/* the horizon.                                                         */
+#define day_civil_twilight_length(year,month,day,lon,lat)  \
+        __daylen__( year, month, day, lon, lat, -6.0, 0 )
+
+/* This macro computes the length of the day, incl. nautical twilight.  */
+/* Nautical twilight starts/ends when the Sun's center is 12 degrees    */
+/* below the horizon.                                                   */
+#define day_nautical_twilight_length(year,month,day,lon,lat)  \
+        __daylen__( year, month, day, lon, lat, -12.0, 0 )
+
+/* This macro computes the length of the day, incl. astronomical twilight. */
+/* Astronomical twilight starts/ends when the Sun's center is 18 degrees   */
+/* below the horizon.                                                      */
+#define day_astronomical_twilight_length(year,month,day,lon,lat)  \
+        __daylen__( year, month, day, lon, lat, -18.0, 0 )
+
+
+/* This macro computes times for sunrise/sunset.                      */
+/* Sunrise/set is considered to occur when the Sun's upper limb is    */
+/* 35 arc minutes below the horizon (this accounts for the refraction */
+/* of the Earth's atmosphere).                                        */
+#define sun_rise_set(year,month,day,lon,lat,rise,set)  \
+        __sunriset__( year, month, day, lon, lat, -35.0/60.0, 1, rise, set )
+
+/* This macro computes the start and end times of civil twilight.       */
+/* Civil twilight starts/ends when the Sun's center is 6 degrees below  */
+/* the horizon.                                                         */
+#define civil_twilight(year,month,day,lon,lat,start,end)  \
+        __sunriset__( year, month, day, lon, lat, -6.0, 0, start, end )
+
+/* This macro computes the start and end times of nautical twilight.    */
+/* Nautical twilight starts/ends when the Sun's center is 12 degrees    */
+/* below the horizon.                                                   */
+#define nautical_twilight(year,month,day,lon,lat,start,end)  \
+        __sunriset__( year, month, day, lon, lat, -12.0, 0, start, end )
+
+/* This macro computes the start and end times of astronomical twilight.   */
+/* Astronomical twilight starts/ends when the Sun's center is 18 degrees   */
+/* below the horizon.                                                      */
+#define astronomical_twilight(year,month,day,lon,lat,start,end)  \
+        __sunriset__( year, month, day, lon, lat, -18.0, 0, start, end )
+
+
+/* Function prototypes */
+
+double __daylen__( int year, int month, int day, double lon, double lat,
+                   double altit, int upper_limb );
+
+int __sunriset__( time_t ts, double lon, double lat,
+                  double altit, int upper_limb, double *rise, double *set );
+
+void sunpos( double d, double *lon, double *r );
+
+void sun_RA_dec( double d, double *RA, double *dec, double *r );
+
+double revolution( double x );
+
+double rev180( double x );
+
+double GMST0( double d );
+