/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2001-2006 Vivid Solutions
* (C) 2001-2008, Open Source Geospatial Foundation (OSGeo)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library 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
* Lesser General Public License for more details.
*/
package org.geotools.geometry.iso.topograph2D.index;
/**
* Models an Event point within the Sweep Line Intersection Algorithm
*
*
* @source $URL$
*/
public class SweepLineEvent implements Comparable {
public static final int INSERT = 1;
public static final int DELETE = 2;
Object edgeSet; // used for red-blue intersection detection
private double xValue;
private int eventType;
private SweepLineEvent insertEvent; // null if this is an INSERT event
private int deleteEventIndex;
private Object obj;
/**
*
* @param edgeSet
* @param x
* @param insertEvent
* @param obj
*/
public SweepLineEvent(Object edgeSet, double x, SweepLineEvent insertEvent,
Object obj) {
this.edgeSet = edgeSet;
xValue = x;
this.insertEvent = insertEvent;
this.eventType = INSERT;
if (insertEvent != null)
eventType = DELETE;
this.obj = obj;
}
public boolean isInsert() {
return insertEvent == null;
}
public boolean isDelete() {
return insertEvent != null;
}
public SweepLineEvent getInsertEvent() {
return insertEvent;
}
public int getDeleteEventIndex() {
return deleteEventIndex;
}
public void setDeleteEventIndex(int deleteEventIndex) {
this.deleteEventIndex = deleteEventIndex;
}
public Object getObject() {
return obj;
}
/**
* ProjectionEvents are ordered first by their x-value, and then by their
* eventType. It is important that Insert events are sorted before Delete
* events, so that items whose Insert and Delete events occur at the same
* x-value will be correctly handled.
*/
public int compareTo(Object o) {
SweepLineEvent pe = (SweepLineEvent) o;
if (xValue < pe.xValue)
return -1;
if (xValue > pe.xValue)
return 1;
if (eventType < pe.eventType)
return -1;
if (eventType > pe.eventType)
return 1;
return 0;
}
}