/*
- * Copyright (C) 2009 Andy Spencer <spenceal@rose-hulman.edu>
+ * Copyright (C) 2009-2010 Andy Spencer <andy753421@gmail.com>
*
* 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
#ifndef __GIS_UTIL_H__
#define __GIS_UTIL_H__
+#include <glib.h>
+
+/**
+ * EARTH_R:
+ *
+ * Radius of the earth
+ */
#define EARTH_R (6371000)
+
+/**
+ * EARTH_C:
+ *
+ * Circumference of the earth at the equator
+ */
#define EARTH_C (2*G_PI*EARTH_R)
+
+/**
+ * NORTH:
+ *
+ * Latitude at the north poll
+ */
#define NORTH 90
+
+/**
+ * SOUTH:
+ *
+ * Latitude at the south poll
+ */
#define SOUTH -90
+
+/**
+ * EAST:
+ *
+ * Eastern most longitude
+ */
#define EAST 180
+
+/**
+ * WEST:
+ *
+ * Western most longitude
+ */
#define WEST -180
+/***************
+ * Conversions *
+ ***************/
/**
- * Terms
- * -----
- * deg - Degrees
- * rad - Radians, also radius
- * m - Meters, for earth-based distances
- * px - Pixels, for screen-based distances
+ * azim2lon:
+ * @azim: the azimuth in radians
*
- * 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
+ * Convert azimuth to longitude
*
- * 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
+ * Returns: the longitude
+ */
+#define azim2lon(azim) ((azim)*180/G_PI)
+
+/**
+ * lon2azim:
+ * @lon: the longitude
*
- * x - 0° lon is positive
- * y - 90° lon is positive
- * z - North pole is positive
+ * Convert longitude to azimuth
*
- * llh - lat,lon,height
- * lle - lat,lon,elev
- * llr - lat,lon,rad
- * pol - incl,azim,rad
- * xyz - x,y,z
+ * Returns: the azimuth in radians
*/
+#define lon2azim(lon) ((lon)*G_PI/180)
/**
- * 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
+ * incl2lat:
+ * @incl: the inclination in radians
+ *
+ * Convert inclination to latitude
*
- * 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
+ * Returns: the latitude
*/
-
-#define azim2lon(azim) ((azim)*180/G_PI)
-#define lon2azim(lon) ((lon)*G_PI/180)
#define incl2lat(incl) (90-(incl)*180/G_PI)
+
+/**
+ * lat2incl:
+ * @lat: the latitude
+ *
+ * Convert latitude to inclination
+ *
+ * Returns: the inclination in radians
+ */
#define lat2incl(lat) ((90-(lat))*G_PI/180)
+
+/**
+ * rad2elev:
+ * @rad: the radius in meters
+ *
+ * Convert radius to elevation
+ *
+ * Returns: the elevation in meters above the earth surface
+ */
#define rad2elev(rad) ((rad)-EARTH_R)
+
+/**
+ * elev2rad:
+ * @elev: the elevation in meters above the earth surface
+ *
+ * Convert elevation to radius
+ *
+ * Returns: the radius in meters
+ */
#define elev2rad(elev) ((elev)+EARTH_R)
+/**
+ * deg2rad:
+ * @deg: the angle in degrees
+ *
+ * Convert degrees to radians
+ *
+ * Returns: the angle in radians
+ */
#define deg2rad(deg) (((deg)*G_PI)/180.0)
+
+/**
+ * rad2deg:
+ * @rad: the angle in radians
+ *
+ * Convert radians to degrees
+ *
+ * Returns: the angle in degrees
+ */
#define rad2deg(rad) (((rad)*180.0)/G_PI)
+
+/*************
+ * Datatypes *
+ *************/
+
+/* GisPoint */
+typedef struct _GisPoint GisPoint;
+struct _GisPoint {
+ gdouble lat, lon, elev;
+};
+
+void gis_point_set_lle(GisPoint *point,
+ gdouble lat, gdouble lon, gdouble elev);
+
+/* GisBounds */
+typedef struct _GisBounds GisBounds;
+struct _GisBounds {
+ gdouble n, s, e, w;
+};
+
+void gis_bounds_set_bounds(GisBounds *bounds,
+ gdouble n, gdouble s, gdouble e, gdouble w);
+
+
+/********
+ * Misc *
+ ********/
+/**
+ * FOV_DIST:
+ *
+ * Used by GisOpenGL to set up the drawing window
+ */
#define FOV_DIST 2000.0
+
+/**
+ * MPPX:
+ * @dist: the distance between the eye and the point in question
+ *
+ * Get the resolution that a point would be drawn at on the screen
+ *
+ * Returns: the resolution in meters per pixel
+ */
#define MPPX(dist) (4*dist/FOV_DIST)
void lle2xyz(gdouble lat, gdouble lon, gdouble elev,
projects / grits / blobdiff