Bounds.java

/**
 * This file is part of OSM2ShareNav 
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation. 
 * See COPYING.
 *
 * Copyright (c) 2007 Harald Mueller
 */

package net.sharenav.osmToShareNav.model;

import net.sharenav.osmToShareNav.MyMath;

/**
 * This class holds the four values of a bounding box and provides methods
 * to makes checks against it.
 */
public class Bounds implements Cloneable {
		public float minLat = 90f;
		public float maxLat = -90f;
		public float minLon = 180f;
		public float maxLon = -180f;


		/**
		 * @return Minimum latitude (southern edge) of the bounding box in degrees.
		 */
		public float getMinLat() {
			return minLat;
		}
		
		/**
		 * @return Maximum latitude (northern edge) of the bounding box in degrees.
		 */
		public float getMaxLat() {
			return maxLat;
		}
		
		/**
		 * @return Minimum longitude (western edge) of the bounding box in degrees.
		 */
		public float getMinLon() {
			return minLon;
		}
		
		/**
		 * @return Maximum longitude (eastern edge) of the bounding box in degrees.
		 */
		public float getMaxLon() {
			return maxLon;
		}

		/**
		 * Extends, if necessary, this bounding box so it also includes this point.
		 * @param lat Latitude in degrees
		 * @param lon Longitude in degrees
		 */
		public void extend(float lat, float lon) {
			if (lat < minLat) {
				minLat = lat;
			}
			if (lat > maxLat) {
				maxLat = lat;
			}
			if (lon < minLon) {
				minLon = lon;
			}
			if (lon > maxLon) {
				maxLon = lon;
			}
		}

		/**
		 * Extends, if necessary, this bounding box so it also includes this point.
		 * @param lat Latitude in degrees
		 * @param lon Longitude in degrees
		 */
		public void extend(double lat, double lon) {
			extend((float)lat, (float)lon);
		}

		/**
		 * Extends, if necessary, this bounding box so it also includes the passed
		 * bounding box.
		 * @param b Bounding box to include
		 */
		public void extend(Bounds b) {
			extend(b.minLat, b.minLon);
			extend(b.maxLat, b.maxLon);
		}
		
		public boolean isMostlyIn(Bounds testBound) {
			float centLat = (testBound.maxLat + testBound.minLat) / 2;
			float centLon = (testBound.maxLon + testBound.minLon) / 2;
			if (centLat < minLat) {
				return false;
			}
			if (centLon < minLon) {
				return false;
			}
			if (centLat > maxLat) {
				return false;
			}
			if (centLon > maxLon) {
				return false;
			}
			return true;
		}

		public boolean isCompleteIn(Bounds testBound) {
			if (testBound.minLat < minLat) {
				return false;
			}
			if (testBound.minLon < minLon) {
				return false;
			}
			if (testBound.maxLat > maxLat) {
				return false;
			}
			if (testBound.maxLon > maxLon) {
				return false;
			}
			return true;
		}

		/**
		 * test if the tested coordinate is inside this boundaries
		 * @param lat lat part of tested coordinate
		 * @param lon lon part of tested coordinate
		 * @return true if test coordinate is inside of this boundaries
		 */
		public boolean isIn(float lat, float lon) {
			if (lat < minLat) {
				return false;
			}
			if (lon < minLon) {
				return false;
			}
			if (lat > maxLat) {
				return false;
			}
			if (lon > maxLon) {
				return false;
			}
			return true;
		}
		
		public boolean isInOrAlmostIn(float lat, float lon) {
			if (lat < minLat - 0.005) {
				return false;
			}
			if (lon < minLon - 0.005) {
				return false;
			}
			if (lat > maxLat + 0.005) {
				return false;
			}
			if (lon > maxLon + 0.005) {
				return false;
			}
			return true;
		}
		
		public boolean isIn(double lat, double lon) {
			return isIn((float)lat, (float) lon);
		}

		/**
		 * Checks if the node is on the boundary.
		 * @param n Node to check
		 * @return True if n is on the boundary
		 */
		public boolean isOnBoundary(Node n) {
			return (n.getLat() == minLat || n.getLat() == maxLat || 
					n.getLon() == minLon || n.getLon() == maxLon);
		}

		@Override
		public Bounds clone() {
			Bounds b = new Bounds();
			b.maxLat = maxLat;
			b.minLat = minLat;
			b.maxLon = maxLon;
			b.minLon = minLon;
			return b;
		}
		
		/**
		 * Create two boundaries out of this bound by dividing it into two pieces.
		 * The orientation will be chosen so that length:width will be nearest 1:1
		 * @return an array of two bounds.
		 */
		public Bounds[] split(){
			Bounds[] ret = new Bounds[2];
			if ((maxLat-minLat) > (maxLon-minLon)){
				float splitLat=(minLat+maxLat)/2;
				ret[0]=clone();
				ret[0].maxLat=splitLat;
				ret[1]=clone();
				ret[1].minLat=splitLat;
			} else {
				float splitLon=(minLon+maxLon)/2;
				ret[0]=clone();
				ret[0].maxLon=splitLon;
				ret[1]=clone();
				ret[1].minLon=splitLon;				
			}
			return ret;
		}

		@Override
		public String toString() {
			return ("[Bound (" + minLat + "|" + minLon+")(" + maxLat + "|" + maxLon +
				") fixptlatspan=" + getFixPtLatSpan() + 
				" fixptlonspan=" + getFixPtLonSpan() + 
				"]");
		}

		/**
		 * @return
		 */
		private int getFixPtLonSpan() {
			return (int)(MyMath.degToRad(maxLon - minLon) * MyMath.FIXPT_MULT);
		}

		/**
		 * @return
		 */
		private int getFixPtLatSpan() {
			return (int)(MyMath.degToRad(maxLat - minLat) * MyMath.FIXPT_MULT);
		}
		
		public int getFixPtSpan(){
			return Math.max(getFixPtLonSpan(), getFixPtLatSpan());
		}

		public String toPropertyString(int regionNr) {
			return	"region." + regionNr + ".lat.min = " + minLat + "\r\n" +
					"region." + regionNr + ".lon.min = " + minLon + "\r\n" +
					"region." + regionNr + ".lat.max = " + maxLat + "\r\n" +
					"region." + regionNr + ".lon.max = " + maxLon + "\r\n";
		}

}