core/org.eclipse.stem.loggers.imagewriter/src/org/eclipse/stem/loggers/imagewriter/logger/projections/Mercator.java

/*******************************************************************************
 * Copyright (c) 2011 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.stem.loggers.imagewriter.logger.projections;

import java.awt.geom.Rectangle2D;



/**
 * Implementation of Equirectangular map projection.  
 * In terms of the existing coordinate system implied
 * in the Globe system, this projection does nothing as
 * this is the implied base coordinate system
 * 
 * @see http://mathworld.wolfram.com/EquirectangularProjection.html
 *
 */
public class Mercator implements IMapProjection
{
	
	public static final double MAX_LAT = 85.05113;
	public static final double MIN_LAT = -85.05113;
	
	public static final Rectangle2D PROJECTION_BOUNDS = new Rectangle2D.Double(-180.0, -180.0, 360.0, 360.0);

	/**
	 * 
	 */
	public Mercator()
	{
		super();
	}

	/* (non-Javadoc)
	 * @see com.ibm.almaden.omniglobe.projection.IMapProjection#project(java.awt.geom.Point2D)
	 */
	public double[] project(double lat, double lon) 
	{
		if (Math.abs(lat) > MAX_LAT) {
			return null;
		}
		
		double latR = Math.toRadians(lat);
		latR = Math.toDegrees(Math.log(Math.tan(latR)+1.0/Math.cos(latR)));

		return new double[] {latR,lon};
	}

	/* (non-Javadoc)
	 * @see com.ibm.almaden.omniglobe.projection.IMapProjection#project(java.awt.geom.Point2D, java.awt.geom.Point2D, boolean)
	 */
	public double[] project(double lat, double lon, double lat0, double lon0, boolean distort) 
	{
		return project(lat,lon);
	}

	/* (non-Javadoc)
	 * @see com.ibm.almaden.omniglobe.projection.IMapProjection#inverseProject(java.awt.geom.Point2D)
	 */
	public double[] inverseProject(double lat, double lon)
	{
		return new double[] {lat,lon};
	}
	
	/* (non-Javadoc)
	 * @see com.ibm.almaden.omniglobe.projection.IMapProjection#inverseProject(java.awt.geom.Point2D, java.awt.geom.Point2D, boolean)
	 */
	public double[] inverseProject(double lat, double lon, double lat0, double lon0, boolean distort)
	{
		return inverseProject(lat, lon);
	}
	
	/* (non-Javadoc)
	 * @see com.ibm.almaden.omniglobe.projection.IMapProjection#setOrigin(java.awt.geom.Point2D)
	 */
	public void setOrigin(double lat, double lon)
	{
		//projection is not origin-dependent
		//does nothing
	}
	
	/* (non-Javadoc)
	 * @see com.ibm.almaden.omniglobe.projection.IMapProjection#getBounds()
	 */
	public Rectangle2D getBounds() 
	{
		return PROJECTION_BOUNDS;
	}

}