content: /**
   * This file is part of Aion-Lightning <aion-lightning.org>.
   *
   *  Aion-Lightning 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.
   *
   *  Aion-Lightning 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 Aion-Lightning.
   *  If not, see <http://www.gnu.org/licenses/>.
   */
  package com.aionemu.gameserver.geoEngine.scene;
  
  import com.aionemu.gameserver.geoEngine.math.Vector3f;
  
  /**
   * An eight sided box.
   * <p/>
   * A {@code Box} is defined by a minimal point and a maximal point. The eight vertices that make the box are then computed, they are computed in such a way as to generate an axis-aligned box.
   * <p/>
   * This class does not control how the geometry data is generated, see {@link Box} for that.
   *
   * @author <a href="mailto:ianp@ianp.org">Ian Phillips</a>
   * @version $Revision: 4131 $, $Date: 2009-03-19 16:15:28 -0400 (Thu, 19 Mar 2009) $
   */
  public abstract class AbstractBox extends Mesh {
  
  	public final Vector3f center = new Vector3f(0f, 0f, 0f);
  	public float xExtent, yExtent, zExtent;
  
  	public AbstractBox() {
  		super();
  	}
  
  	/**
  	 * Gets the array or vectors representing the 8 vertices of the box.
  	 *
  	 * @return a newly created array of vertex vectors.
  	 */
  	protected final Vector3f[] computeVertices() {
  		Vector3f[] axes = { Vector3f.UNIT_X.mult(xExtent), Vector3f.UNIT_Y.mult(yExtent), Vector3f.UNIT_Z.mult(zExtent) };
  		return new Vector3f[] { center.subtract(axes[0]).subtractLocal(axes[1]).subtractLocal(axes[2]), center.add(axes[0]).subtractLocal(axes[1]).subtractLocal(axes[2]), center.add(axes[0]).addLocal(axes[1]).subtractLocal(axes[2]), center.subtract(axes[0]).addLocal(axes[1]).subtractLocal(axes[2]), center.add(axes[0]).subtractLocal(axes[1]).addLocal(axes[2]), center.subtract(axes[0]).subtractLocal(axes[1]).addLocal(axes[2]), center.add(axes[0]).addLocal(axes[1]).addLocal(axes[2]), center.subtract(axes[0]).addLocal(axes[1]).addLocal(axes[2]) };
  	}
  
  	/**
  	 * Convert the indices into the list of vertices that define the box's geometry.
  	 */
  	protected abstract void duUpdateGeometryIndices();
  
  	/**
  	 * Update the normals of each of the box's planes.
  	 */
  	protected abstract void duUpdateGeometryNormals();
  
  	/**
  	 * Update the position of the vertices that define the box.
  	 * <p/>
  	 * These eight points are determined from the minimum and maximum point.
  	 */
  	protected abstract void duUpdateGeometryVertices();
  
  	/**
  	 * Get the center point of this box.
  	 */
  	public final Vector3f getCenter() {
  		return center;
  	}
  
  	/**
  	 * Get the x-axis size (extent) of this box.
  	 */
  	public final float getXExtent() {
  		return xExtent;
  	}
  
  	/**
  	 * Get the y-axis size (extent) of this box.
  	 */
  	public final float getYExtent() {
  		return yExtent;
  	}
  
  	/**
  	 * Get the z-axis size (extent) of this box.
  	 */
  	public final float getZExtent() {
  		return zExtent;
  	}
  
  	/**
  	 * Rebuilds the box after a property has been directly altered.
  	 * <p/>
  	 * For example, if you call {@code getXExtent().x = 5.0f} then you will need to call this method afterwards in order to update the box.
  	 */
  	public final void updateGeometry() {
  		duUpdateGeometryVertices();
  		duUpdateGeometryNormals();
  		duUpdateGeometryIndices();
  	}
  
  	/**
  	 * Rebuilds this box based on a new set of parameters.
  	 * <p/>
  	 * Note that the actual sides will be twice the given extent values because the box extends in both directions from the center for each extent.
  	 *
  	 * @param center
  	 *            the center of the box.
  	 * @param x
  	 *            the x extent of the box, in each directions.
  	 * @param y
  	 *            the y extent of the box, in each directions.
  	 * @param z
  	 *            the z extent of the box, in each directions.
  	 */
  	public final void updateGeometry(Vector3f center, float x, float y, float z) {
  		if (center != null) {
  			this.center.set(center);
  		}
  		this.xExtent = x;
  		this.yExtent = y;
  		this.zExtent = z;
  		updateGeometry();
  	}
  
  	/**
  	 * Rebuilds this box based on a new set of parameters.
  	 * <p/>
  	 * The box is updated so that the two opposite corners are {@code minPoint} and {@code maxPoint}, the other corners are created from those two positions.
  	 *
  	 * @param minPoint
  	 *            the new minimum point of the box.
  	 * @param maxPoint
  	 *            the new maximum point of the box.
  	 */
  	public final void updateGeometry(Vector3f minPoint, Vector3f maxPoint) {
  		center.set(maxPoint).addLocal(minPoint).multLocal(0.5f);
  		float x = maxPoint.x - center.x;
  		float y = maxPoint.y - center.y;
  		float z = maxPoint.z - center.z;
  		updateGeometry(center, x, y, z);
  	}
  }
  