/***********************************************************************

 * mt4j Copyright (c) 2008 - 2009 C.Ruff, Fraunhofer-Gesellschaft All rights reserved.

 *  

 *   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/>.

 *

 ***********************************************************************/

package org.mt4j.util.math;



/**

 * The Class Ray.

 * 

 * @author C.Ruff

 */

public class Ray {

	

	/** The ray start point. */

	private Vector3D rayStartPoint;

	

	/** The point in ray direction. */

	private Vector3D pointInRayDirection;

	

	/** The ray direction. */

	private Vector3D rayDirection;

	

	

	/**

	 * Instantiates a new ray.

	 * 

	 * @param ray the ray

	 */

	public Ray(Ray ray){

		super();

		this.rayStartPoint 			= ray.getRayStartPoint().getCopy();

		this.pointInRayDirection 	= ray.getPointInRayDirection().getCopy();

	}

	

	/**

	 * Instantiates a new ray.

	 * 

	 * @param rayStartPoint the ray start point

	 * @param pointInRayDirection the point in ray direction

	 */

	public Ray(Vector3D rayStartPoint, Vector3D pointInRayDirection) {

		super();

		this.rayStartPoint 			= rayStartPoint;

		this.pointInRayDirection 	= pointInRayDirection;

	}

	

	

	/**

	 * Gets the ray direction.

	 * 

	 * @return the ray direction

	 */

	public Vector3D getRayDirection(){

		return pointInRayDirection.getSubtracted(rayStartPoint);

	}

	

	/**

	 * Gets the ray direction normalized.

	 * 

	 * @return the ray direction normalized

	 */

	public Vector3D getRayDirectionNormalized(){

		return getRayDirection().normalizeLocal();

	}



	/**

	 * Gets the point in ray direction.

	 * 

	 * @return the point in ray direction

	 */

	public Vector3D getPointInRayDirection() {

		return pointInRayDirection;

	}



	/**

	 * Sets the point in ray direction.

	 * 

	 * @param pointInRayDirection the new point in ray direction

	 */

	public void setPointInRayDirection(Vector3D pointInRayDirection) {

		this.pointInRayDirection = pointInRayDirection;

	}



	/**

	 * Gets the ray start point.

	 * 

	 * @return the ray start point

	 */

	public Vector3D getRayStartPoint() {

		return rayStartPoint;

	}



	/**

	 * Sets the ray start point.

	 * 

	 * @param rayStartPoint the new ray start point

	 */

	public void setRayStartPoint(Vector3D rayStartPoint) {

		this.rayStartPoint = rayStartPoint;

	}

	

	/**

	 * Transforms the ray.

	 * The direction vector is multiplied with the transpose of the matrix.

	 * 

	 * @param m the m

	 */

	public void transform(Matrix m){

		rayStartPoint.transform(m);

		

//		pointInRayDirection.transformNormal(m);

//		pointInRayDirection.normalize(); //FIXME TRIAL REMOVE? NO oder vielleicht gleich bei transformNOrmal mit rein?

//		

//		pointInRayDirection = rayStartPoint.plus(pointInRayDirection);

		

		pointInRayDirection.transform(m);

	}

	

	/**

	 * Calculates and returns the direction vector.

	 * This is calced by subtracting the rayStartpoint from the point in the rays direction.

	 * 

	 * @return the direction

	 */

	public Vector3D getDirection(){

		return pointInRayDirection.getSubtracted(rayStartPoint);

	}

	

	/**

	 * Returns a new ray, transformed by the matrix.

	 * 

	 * @param ray the ray

	 * @param m the m

	 * 

	 * @return the transformed ray

	 */

	public static Ray getTransformedRay(Ray ray, Matrix m){

//		if (!Matrix.equalIdentity(m)){

			//Get a copy of the origonal ray

			Ray transformedRay = new Ray(ray);

			transformedRay.transform(m);

			return transformedRay;

//		}else{

//			return ray;

//		}

	}

	

	@Override

	public String toString(){

		return "Ray start: " + this.rayStartPoint + " PointInRayDirection: " + this.pointInRayDirection + " " + super.toString();

	}



}