001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.math3.geometry.partitioning;
018
019import org.apache.commons.math3.geometry.Point;
020import org.apache.commons.math3.geometry.Space;
021
022/** Class holding the result of point projection on region boundary.
023 * <p>This class is a simple placeholder, it does not provide any
024 * processing methods.</p>
025 * <p>Instances of this class are guaranteed to be immutable</p>
026 * @param <S> Type of the space.
027 * @since 3.3
028 * @see AbstractRegion#projectToBoundary(Point)
029 */
030public class BoundaryProjection<S extends Space> {
031
032    /** Original point. */
033    private final Point<S> original;
034
035    /** Projected point. */
036    private final Point<S> projected;
037
038    /** Offset of the point with respect to the boundary it is projected on. */
039    private final double offset;
040
041    /** Constructor from raw elements.
042     * @param original original point
043     * @param projected projected point
044     * @param offset offset of the point with respect to the boundary it is projected on
045     */
046    public BoundaryProjection(final Point<S> original, final Point<S> projected, final double offset) {
047        this.original  = original;
048        this.projected = projected;
049        this.offset    = offset;
050    }
051
052    /** Get the original point.
053     * @return original point
054     */
055    public Point<S> getOriginal() {
056        return original;
057    }
058
059    /** Projected point.
060     * @return projected point, or null if there are no boundary
061     */
062    public Point<S> getProjected() {
063        return projected;
064    }
065
066    /** Offset of the point with respect to the boundary it is projected on.
067     * <p>
068     * The offset with respect to the boundary is negative if the {@link
069     * #getOriginal() original point} is inside the region, and positive otherwise.
070     * </p>
071     * <p>
072     * If there are no boundary, the value is set to either {@code
073     * Double.POSITIVE_INFINITY} if the region is empty (i.e. all points are
074     * outside of the region) or {@code Double.NEGATIVE_INFINITY} if the region
075     * covers the whole space (i.e. all points are inside of the region).
076     * </p>
077     * @return offset of the point with respect to the boundary it is projected on
078     */
079    public double getOffset() {
080        return offset;
081    }
082
083}