Merging GisWorld and GisView into GisViewer

[grits] / src / gis-util.h

diff --git a/src/gis-util.h b/src/gis-util.h
new file mode 100644 (file)
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--- /dev/null
+++ b/src/gis-util.h
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2009 Andy Spencer <spenceal@rose-hulman.edu>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GIS_UTIL_H__
+#define __GIS_UTIL_H__
+
+#define EARTH_R (6371000)
+#define EARTH_C (2*M_PI*EARTH_R)
+#define NORTH  90
+#define SOUTH -90
+#define EAST  180
+#define WEST -180
+
+/**
+ * Terms
+ * -----
+ * deg    - Degrees
+ * rad    - Radians, also radius
+ * m      - Meters, for earth-based distances
+ * px     - Pixels, for screen-based distances
+ *
+ * height - Height, the distance above the geoid (ground)
+ * elev   - Elevation, the distance above the spheroid
+ * rad    - Radius, the distance from the center of the earth
+ *
+ * lat    - Latitude, amount north-south, -90 (S) .. 90 (N)
+ * lon    - Longitude, amount east-west, -180 (W) .. 180 (E)
+ * incl   - Inclination, polar equiv of  latitude, Pi .. 0
+ * azim   - Azimuth, polar equiv of longitude, -Pi .. Pi
+ *
+ * x      -  0° lon is positive
+ * y      - 90° lon is positive
+ * z      - North pole is positive
+ *
+ * llh    - lat,lon,height
+ * lle    - lat,lon,elev
+ * llr    - lat,lon,rad
+ * pol    - incl,azim,rad
+ * xyz    - x,y,z
+ */
+
+/**
+ *             lat    lon   elev ->      x      y      z
+ * lle2xyz:    0.0,   0.0,   0.0 ->    0.0,   0.0,  10.0
+ * lle2xyz:   90.0,   0.0,   0.0 ->    0.0,  10.0,   0.0
+ * lle2xyz:    0.0,  90.0,   0.0 ->   10.0,   0.0,   0.0
+ *
+ *               x      y      z ->    lat    lon   elev
+ * xyz2lle:   10.0,   0.0,   0.0 ->    0.0,  90.0,   0.0
+ * xyz2lle:    0.0,  10.0,   0.0 ->   90.0,   0.0,   0.0
+ * xyz2lle:    0.0,   0.0,  10.0 ->    0.0,   0.0,   0.0
+ */
+
+#define azim2lon(azim) ((azim)*180/M_PI)
+#define lon2azim(lon)  ((lon)*M_PI/180)
+#define incl2lat(incl) (90-(incl)*180/M_PI)
+#define lat2incl(lat)  ((90-(lat))*M_PI/180)
+#define rad2elev(rad)  ((rad)-EARTH_R)
+#define elev2rad(elev) ((elev)+EARTH_R)
+
+#define deg2rad(deg) (((deg)*M_PI)/180.0)
+#define rad2deg(rad) (((rad)*180.0)/M_PI)
+
+#define FOV_DIST   2000.0
+#define MPPX(dist) (4*dist/FOV_DIST)
+
+void lle2xyz(gdouble lat, gdouble lon, gdouble elev,
+               gdouble *x, gdouble *y, gdouble *z);
+
+void xyz2lle(gdouble x, gdouble y, gdouble z,
+               gdouble *lat, gdouble *lon, gdouble *elev);
+
+void xyz2ll(gdouble x, gdouble y, gdouble z,
+               gdouble *lat, gdouble *lon);
+
+gdouble ll2m(gdouble lon_dist, gdouble lat);
+
+gdouble distd(gdouble *a, gdouble *b);
+
+#endif