Add simple angle diff function

diff --git a/src/latlon.c b/src/latlon.c
index 8827dc1eaa8400b39ee8ea756fc0250d5d5aeba0..943510c855a7eeb70fb8be15d914a51b088db73b 100644 (file)
--- a/src/latlon.c
+++ b/src/latlon.c
@@ -56,6 +56,20 @@ UNITS_TEXT[UNITS_MI] = _("mi.");
 UNITS_TEXT[UNITS_NM] = _("n.m.");
 }
 
+gfloat
+angle_diff(gfloat a, gfloat b)
+{
+gfloat tmax, tmin, t;
+
+tmax=MAX(a,b);
+tmin=MIN(a,b);
+
+t=tmax-tmin;
+if (t>180) t-=360;
+
+return t;
+}
+
 static inline gdouble 
 magnitude(gdouble x1, gdouble y1, gdouble x2, gdouble y2)
 {
@@ -244,34 +258,27 @@ gdouble acoor=fabs(coor);
 switch (degformat) {
        case DDPDDDDD:
                g_sprintf(scoor, "%.5f°", coor);
-               break;
+       break;
        case DDPDDDDD_NSEW:
-               g_sprintf(scoor, "%.5f° %c", acoor,
-                       coor < 0.f ? neg_char : pos_char);
-               break;
-
+               g_sprintf(scoor, "%.5f° %c", acoor, coor < 0.f ? neg_char : pos_char);
+       break;
        case DD_MMPMMM:
-               g_sprintf(scoor, "%d°%06.3f'",
-                       (int)coor, (acoor - (int)acoor) * 60.0);
-               break;
+               g_sprintf(scoor, "%d°%06.3f'", (int)coor, (acoor - (int)acoor) * 60.0);
+       break;
        case DD_MMPMMM_NSEW:
-               g_sprintf(scoor, "%d°%06.3f' %c",
-                       (int)acoor, (acoor - (int)acoor) * 60.0,
-                       coor < 0.f ? neg_char : pos_char);
-               break;
-
+               g_sprintf(scoor, "%d°%06.3f' %c", (int)acoor, (acoor - (int)acoor) * 60.0,     coor < 0.f ? neg_char : pos_char);
+       break;
        case DD_MM_SSPS:
                min = (acoor - (int)acoor) * 60.0;
-               g_sprintf(scoor, "%d°%02d'%04.1f\"", (int)coor, (int)min,
-                       ((min - (int)min) * 60.0));
-               break;
+               g_sprintf(scoor, "%d°%02d'%04.1f\"", (int)coor, (int)min, ((min - (int)min) * 60.0));
+       break;
        case DD_MM_SSPS_NSEW:
                min = (acoor - (int)acoor) * 60.0;
-               g_sprintf(scoor, "%d°%02d'%04.1f\" %c", (int)acoor, (int)min,
-                       ((min - (int)min) * 60.0),
-                       coor < 0.f ? neg_char : pos_char);
-               break;
-       default:;
+               g_sprintf(scoor, "%d°%02d'%04.1f\" %c", (int)acoor, (int)min, ((min - (int)min) * 60.0), coor < 0.f ? neg_char : pos_char);
+       break;
+       default:
+               g_return_if_reached();
+       break;
 }
 }
 

diff --git a/src/latlon.h b/src/latlon.h
index 8f5257dd8ed15ba3e87a8583a69df393cefcf91d..11bf85c5322477b9ab17fd1bf0221110b780b44d 100644 (file)
--- a/src/latlon.h
+++ b/src/latlon.h
@@ -59,13 +59,17 @@ void latlon_init(void);
 
 gint32 lon2mp_int(gdouble lon);
 gint32 lat2mp_int(gdouble lat);
+
 gdouble calculate_distance(gdouble lat1, gdouble lon1, gdouble lat2, gdouble lon2);
 gdouble calculate_ddistance(gint lat1, gint lon1, gint lat2, gint lon2);
 gulong calculate_idistance(gint lat1, gint lon1, gint lat2, gint lon2);
 gulong calculate_idistance_cmp(gint lat1, gint lon1, gint lat2, gint lon2);
+
 gdouble calculate_course_rad(gdouble lat1, gdouble lon1, gdouble lat2, gdouble lon2);
 gdouble calculate_course(gdouble lat1, gdouble lon1, gdouble lat2, gdouble lon2);
 
+gfloat angle_diff(gfloat a, gfloat b);
+
 gboolean distance_point_to_line(gdouble x, gdouble y, gdouble x1, gdouble y1, gdouble x2, gdouble y2, gdouble *d);
 
 guint32 xy2tile(guint x, guint y);