com.ctreber.acearth
Class MapDataReader

java.lang.Object
  com.ctreber.acearth.MapDataReader

public class MapDataReader
extends Object

The map data file is a big array of short (16-bit) ints, as follows: - it is a sequence of closed curves - the first value in a curve is the number of points in the curve - the second value in a curve indicates land/water (1 or -1, respectively) - this is followed by an [x,y,z] triple that indicates a point on the unit sphere (each of x, y, and z has been scaled by 30000), where the x axis points "to the right" (towards 0 N 90 E), the y axis points "up" (towards the north pole), and the z axis points "out of the screen" (towards 0 N 0 E). this is the starting point of the curve. - this is followed by (one less than the number of points in the curve) triples [dx,dy,dz]; the [x,y,z] triple for each successive point in the curve is obtained by adding [dx,dy,dz] onto the previous [x,y,z] values. - the curves are [must be!] non-self-intersecting and traced in a counter-clockwise direction the curves are sampled at a (roughly) a 20 mile resolution.

© 2002 Christian Treber, [email protected]

Author:

Christian Treber, [email protected]

Constructor Summary

MapDataReader()

Method Summary

static Polygon[]

readMapData() Read map data.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MapDataReader

public MapDataReader()

Method Detail

readMapData

public static Polygon[] readMapData()
                             throws IOException

Read map data.

Parameters:

pFileName - Map data file name.

Returns:

Array of map polygons.

Throws:

IOException