/*
* Freeplane - mind map editor
* Copyright (C) 2009 Dimitry
*
* This file author is Dimitry
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.freeplane.view.swing.map.link;
import java.awt.Point;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.PathIterator;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
/**
* @author Dimitry Polivaev
* 09.08.2009
*/
public class CollisionDetector {
/** MAXIMAL_RECTANGLE_SIZE_FOR_COLLISION_DETECTION describes itself. */
static final private int MAXIMAL_RECTANGLE_SIZE_FOR_COLLISION_DETECTION = 16;
public boolean detectCollision(final Point p, final Shape shape) {
final Rectangle2D rec = getControlRectangle(p);
final PathIterator pathIterator = shape.getPathIterator(new AffineTransform(),
MAXIMAL_RECTANGLE_SIZE_FOR_COLLISION_DETECTION / 4);
double lastCoords[] = new double[6];
pathIterator.currentSegment(lastCoords);
for (;;) {
pathIterator.next();
final double nextCoords[] = new double[6];
if (pathIterator.isDone() || PathIterator.SEG_CLOSE == pathIterator.currentSegment(nextCoords)) {
break;
}
final double x = Math.min(lastCoords[0], nextCoords[0]) - 1;
final double y = Math.min(lastCoords[1], nextCoords[1]) - 1;
final double w = Math.abs(lastCoords[0] - nextCoords[0]) + 2;
final double h = Math.abs(lastCoords[1] - nextCoords[1]) + 2;
if (rec.intersects(x, y, w, h)) {
return true;
}
lastCoords = nextCoords;
}
return false;
}
private Rectangle2D getControlRectangle(final Point2D p) {
final int side = MAXIMAL_RECTANGLE_SIZE_FOR_COLLISION_DETECTION;
return new Rectangle2D.Double(p.getX() - side / 2, p.getY() - side / 2, side, side);
}
}