/*=========================================================================

  Program:   FusionViewer
  Module:    $RCSfile: PositionModel.java,v $
  Language:  Java
  Date:      $Date: 2007/02/02 19:27:10 $
  Version:   $Revision: 1.3 $
  
  Copyright (c) Insightful Corporation.  All rights reserved.
  See Copyright.txt for details.
  
  This software is distributed WITHOUT ANY WARRANTY; without even
  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  PURPOSE.  See the above copyright notice for more information.

=========================================================================*/

package org.fusionviewer.model;


/**\class PositionModel
 *\brief Stores image coordinates and size in physical scale (millimeters)
 */
public class PositionModel {
	/*
	 * A position in physical coordinates (millimeters)
	 */
	private float[] position;
	/*
	 * Dimension of the coordinates (dimension > 0)
	 */
	private int dimension;

	
	
	/**
	 * Construct a position container.  For example,
	 * new PositionModel(3) creates a 3D position model.
	 * 
	 * @param dimension dimension of the position
	 */
	public PositionModel(int dimension) {
		if (dimension <= 0)
			throw new IllegalArgumentException("Position dimension must be >= 0");
		
		this.position = new float[dimension];
		this.dimension = dimension;
		
	}
	
	/**
	 * Get a component of the position.  The components
	 * are indexed from 0.
	 * 
	 * @param idx position index
	 * @return position at index
	 */
	public float getPosition(int idx) {
		return position[idx];
	}
	
	/**
	 * Get the position as an array.
	 * 
	 * @return the position
	 */
	public float[] getPosition() {
		float[] pos = new float[dimension];
		for (int i = 0; i < dimension; i++)
			pos[i] = position[i];
		
		return pos;
	}
	
	/**
	 * Set a component of the position.  The components are indexed from 0.
	 * 
	 * @param idx component to set
	 * @param value set the position component to this value
	 * @return true if the object was changed
	 */
	public boolean setPosition(int idx, float value) {
		if (position[idx] == value)
			return false;
		
		position[idx] = value;
		
		return true;
	}
	
	/**
	 * Set the position.
	 * 
	 * @param pos an array containing the coordinates
	 * @return true if the object was changed
	 */
	public boolean setPosition(float[] pos) {
		if (dimension != pos.length)
			throw new IllegalArgumentException("New position does not have the expected number of components (" +
						dimension + ')');
		
		boolean positionChanged = false;
		for (int i = 0; i < dimension; i++) {
			if (position[i] != pos[i])
				positionChanged = true;
			
			position[i] = pos[i];
		}
		
		return positionChanged;
	}
}