bundles/common/org.eclipse.apogy.common.math.quickhull3d/src/org/eclipse/apogy/common/math/quickhull3d/FaceList.java

package org.eclipse.apogy.common.math.quickhull3d;

/********************************************************************************
 * Copyright (c) 2018 Agence spatiale canadienne / Canadian Space Agency
 * Contributors: Pierre Allard (Pierre.Allard@canada.ca), Regent L'Archeveque
 * (Regent.Larcheveque@canada.ca), Sebastien Gemme (Sebastien.Gemme@canada.ca),
 * Canadian Space Agency (CSA) - Initial API and implementation
 * 
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 1.0 which is available at
 * http://www.eclipse.org/legal/epl-v10.html.
 * 
 * SPDX-License-Identifier: EPL-1.0
 ********************************************************************************/

class FaceList {
	private Face head;
	private Face tail;

	/**
	 * Clears this list.
	 */
	public void clear() {
		this.head = this.tail = null;
	}

	/**
	 * Adds a vertex to the end of this list.
	 */
	public void add(Face vtx) {
		if (this.head == null) {
			this.head = vtx;
		} else {
			this.tail.next = vtx;
		}
		vtx.next = null;
		this.tail = vtx;
	}

	public Face first() {
		return this.head;
	}

	/**
	 * Returns true if this list is empty.
	 */
	public boolean isEmpty() {
		return this.head == null;
	}
}