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//
// $Id$
//
// Vilya library - tools for developing networked games
// Copyright (C) 2002-2012 Three Rings Design, Inc., All Rights Reserved
// http://code.google.com/p/vilya/
//
// 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; either version 2.1 of the License, or
// (at your option) any later version.
//
// 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.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package com.threerings.puzzle.util;
import java.util.Iterator;
import java.awt.Point;
import static com.threerings.puzzle.Log.log;
/**
* The point set class provides an efficient implementation of a set containing two-dimensional
* point values as (x, y).
*/
public class PointSet
{
/**
* Creates a point set that can contain points within the given range of values.
*
* @param rangeX the maximum x-axis range.
* @param rangeY the maximum y-axis range.
*/
public PointSet (int rangeX, int rangeY)
{
_rangeX = rangeX;
_rangeY = rangeY;
_points = new boolean[rangeX][rangeY];
}
/**
* Adds a point to the set and returns whether the point was already present in the set.
*
* @param x the point x-coordinate.
* @param y the point y-coordinate.
*
* @return true if the point was already present, false if not.
*/
public boolean add (int x, int y)
{
boolean present = _points[x][y];
_points[x][y] = true;
if (!present) {
_count++;
}
return present;
}
/**
* Adds all points in the given set to this set.
*
* @param set the set containing points to add.
*/
public void addAll (PointSet set)
{
Point pt;
Iterator iter = set.iterator();
while ((pt = iter.next()) != null) {
add(pt.x, pt.y);
}
}
/**
* Clears all points from this set.
*/
public void clear ()
{
if (_count == 0) {
// no need to clear anything
return;
}
for (int xx = 0; xx < _rangeX; xx++) {
for (int yy = 0; yy < _rangeY; yy++) {
_points[xx][yy] = false;
}
}
_count = 0;
}
/**
* Returns whether this set contains the given point.
*
* @param x the point x-coordinate.
* @param y the point y-coordinate.
*
* @return true if the set contains the point, false if not.
*/
public boolean contains (int x, int y)
{
return (_points[x][y]);
}
/**
* Returns whether this set is empty.
*
* @return true if the set is empty, false if not.
*/
public boolean isEmpty ()
{
return (_count == 0);
}
/**
* Returns an iterator that iterates over the points in this set, returning them as
* {@link Point} objects. Note that the iterator uses a single point object internally, and so
* callers should create their own copy of the point if they plan to do something fancy with
* it.
*
* @return the iterator over the set's points.
*/
public Iterator iterator ()
{
return new PointIterator();
}
/**
* Removes the given point from the set and returns whether the point was present in the set.
*
* @param x the point x-coordinate.
* @param y the point y-coordinate.
*
* @return true if the point was present, false if not.
*/
public boolean remove (int x, int y)
{
boolean present = _points[x][y];
_points[x][y] = false;
if (present) {
_count--;
}
return present;
}
/**
* Returns the number of points in the set.
*
* @return the number of points.
*/
public int size ()
{
return _count;
}
@Override
public String toString ()
{
StringBuilder buf = new StringBuilder();
buf.append("[");
Iterator iter = iterator();
Point val;
while ((val = iter.next()) != null) {
buf.append("(").append(val.x);
buf.append(",").append(val.y);
buf.append(")");
if (iter.hasNext()) {
buf.append(", ");
}
}
return buf.append("]").toString();
}
protected class PointIterator implements Iterator
{
public boolean hasNext ()
{
return (_curCount < _count);
}
public Point next ()
{
if (_curCount == _count) {
return null;
}
while (!_points[_curX][_curY]) {
advance();
}
_curCount++;
_point.setLocation(_curX, _curY);
if (_curCount < _count) {
advance();
}
return _point;
}
public void remove ()
{
throw new UnsupportedOperationException();
}
protected void advance ()
{
if ((++_curX) >= _rangeX) {
_curX = 0;
_curY++;
}
if (_curY >= _rangeY) {
log.warning("Advanced past point range.");
_curY = 0;
}
}
protected int _curCount = 0;
protected int _curX = 0, _curY = 0;
protected Point _point = new Point();
}
/** The dimensions of the point array. */
protected int _rangeX, _rangeY;
/** The points in the set. */
protected boolean _points[][];
/** The number of points in the set. */
protected int _count;
}