001/**
002 * Copyright (c) 2011, The University of Southampton and the individual contributors.
003 * All rights reserved.
004 *
005 * Redistribution and use in source and binary forms, with or without modification,
006 * are permitted provided that the following conditions are met:
007 *
008 *   *  Redistributions of source code must retain the above copyright notice,
009 *      this list of conditions and the following disclaimer.
010 *
011 *   *  Redistributions in binary form must reproduce the above copyright notice,
012 *      this list of conditions and the following disclaimer in the documentation
013 *      and/or other materials provided with the distribution.
014 *
015 *   *  Neither the name of the University of Southampton nor the names of its
016 *      contributors may be used to endorse or promote products derived from this
017 *      software without specific prior written permission.
018 *
019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
020 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
021 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
022 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
023 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
026 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
028 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
029 */
030package org.openimaj.math.geometry.shape.util.polygon;
031
032import java.util.ArrayList;
033import java.util.List;
034
035import org.openimaj.math.geometry.shape.util.PolygonUtils;
036
037/** */
038public class EdgeTable
039{
040        private List<EdgeNode> m_List = new ArrayList<EdgeNode>();
041
042        /**
043         * @param x
044         * @param y
045         */
046        public void addNode( double x, double y )
047        {
048                EdgeNode node = new EdgeNode();
049                node.vertex.x = x;
050                node.vertex.y = y;
051                m_List.add( node );
052        }
053
054        /**
055         * @param index
056         * @return edge node
057         */
058        public EdgeNode getNode( int index )
059        {
060                return (EdgeNode) m_List.get( index );
061        }
062
063        /**
064         * @param i
065         * @return FWD_MIN
066         */
067        public boolean FWD_MIN( int i )
068        {
069                EdgeNode prev = (EdgeNode) m_List.get( PolygonUtils.PREV_INDEX( i, m_List.size() ) );
070                EdgeNode next = (EdgeNode) m_List.get( PolygonUtils.NEXT_INDEX( i, m_List.size() ) );
071                EdgeNode ith = (EdgeNode) m_List.get( i );
072                return ((prev.vertex.getY() >= ith.vertex.getY()) && (next.vertex.getY() > ith.vertex.getY()));
073        }
074
075        /**
076         * @param i
077         * @return NOT_FMAX
078         */
079        public boolean NOT_FMAX( int i )
080        {
081                EdgeNode next = (EdgeNode) m_List.get( PolygonUtils.NEXT_INDEX( i, m_List.size() ) );
082                EdgeNode ith = (EdgeNode) m_List.get( i );
083                return (next.vertex.getY() > ith.vertex.getY());
084        }
085
086        /**
087         * @param i
088         * @return REV_MIN
089         */
090        public boolean REV_MIN( int i )
091        {
092                EdgeNode prev = (EdgeNode) m_List.get( PolygonUtils.PREV_INDEX( i, m_List.size() ) );
093                EdgeNode next = (EdgeNode) m_List.get( PolygonUtils.NEXT_INDEX( i, m_List.size() ) );
094                EdgeNode ith = (EdgeNode) m_List.get( i );
095                return ((prev.vertex.getY() > ith.vertex.getY()) && (next.vertex.getY() >= ith.vertex.getY()));
096        }
097
098        /**
099         * @param i
100         * @return NOT_RMAX
101         */
102        public boolean NOT_RMAX( int i )
103        {
104                EdgeNode prev = (EdgeNode) m_List.get( PolygonUtils.PREV_INDEX( i, m_List.size() ) );
105                EdgeNode ith = (EdgeNode) m_List.get( i );
106                return (prev.vertex.getY() > ith.vertex.getY());
107        }
108}