/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 1998-2008, 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.math;
import java.awt.geom.Line2D;
import java.awt.geom.Point2D;
import java.util.Random;
import javax.vecmath.Point3d;
import org.junit.*;
import static org.junit.Assert.*;
/**
* Tests the {@link Line} and {@link Plane} classes.
*
*
*
* @source $URL$
* @version $Id$
* @author Martin Desruisseaux (PMO, IRD)
*/
public final class GeometryTest {
/**
* Tolerance factor for comparaisons.
*/
private static final double EPS = 1E-8;
/**
* Tests {@link Line#setLine}.
*/
@Test
public void testLine() {
final Line line = new Line();
line.setLine(new Point2D.Double(-2, 2), new Point2D.Double(8, 22));
assertEquals("slope", 2, line.getSlope(), EPS);
assertEquals("x0", -3, line.getX0(), EPS);
assertEquals("y0", 6, line.getY0(), EPS);
// Horizontal line
line.setLine(new Point2D.Double(-2, 2), new Point2D.Double(8, 2));
assertEquals("slope", 0, line.getSlope(), EPS);
assertTrue ("x0", Double.isInfinite(line.getX0()));
assertEquals("y0", 2, line.getY0(), EPS);
// Vertical line
line.setLine(new Point2D.Double(-2, 2), new Point2D.Double(-2, 22));
assertTrue ("slope", Double.isInfinite(line.getSlope()));
assertEquals("x0", -2, line.getX0(), EPS);
assertTrue ("y0", Double.isInfinite(line.getY0()));
// Horizontal line on the x axis
line.setLine(new Point2D.Double(-2, 0), new Point2D.Double(8, 0));
assertEquals("slope", 0, line.getSlope(), EPS);
assertTrue ("x0", Double.isInfinite(line.getX0()));
assertEquals("y0", 0, line.getY0(), EPS);
// Vertical line on the y axis
line.setLine(new Point2D.Double(0, 2), new Point2D.Double(0, 22));
assertTrue ("slope", Double.isInfinite(line.getSlope()));
assertEquals("x0", 0, line.getX0(), EPS);
assertTrue ("y0", Double.isInfinite(line.getY0()));
}
/**
* Tests {@link Line#isoscelesTriangleBase}.
*/
@Test
public void testIsoscelesTriangleBase() {
final Line test = new Line();
test.setLine(new Point2D.Double(20,30), new Point2D.Double(80,95));
assertEquals("slope", 1.083333333333333333333333, test.getSlope(), EPS);
assertEquals("y0", 8.333333333333333333333333, test.getY0(), EPS);
final double distance = 40;
final Point2D summit = new Point2D.Double(27, -9); // An arbitrary point.
final Line2D base = test.isoscelesTriangleBase(summit, distance);
assertEquals("distance P1", distance, base.getP1().distance(summit), EPS);
assertEquals("distance P2", distance, base.getP2().distance(summit), EPS);
final double x=10; // Can be any arbitrary point.
final double y=8;
assertEquals("nearest colinear point", base.ptLineDist(x,y),
test.nearestColinearPoint(new Point2D.Double(x,y)).distance(x,y), EPS);
}
/**
* Tests {@link Plane#setPlane} methods.
*/
@Test
public void testPlaneFit() {
final Random rd = new Random(457821698762354L);
final Plane plan = new Plane();
final Point3d P1 = new Point3d(100*rd.nextDouble()+25, 100*rd.nextDouble()+25, Math.rint(100*rd.nextDouble()+40));
final Point3d P2 = new Point3d(100*rd.nextDouble()+25, 100*rd.nextDouble()+25, Math.rint(100*rd.nextDouble()+40));
final Point3d P3 = new Point3d(100*rd.nextDouble()+25, 100*rd.nextDouble()+25, Math.rint(100*rd.nextDouble()+40));
plan.setPlane(P1, P2, P3);
assertEquals("P1", P1.z, plan.z(P1.x,P1.y), EPS);
assertEquals("P2", P2.z, plan.z(P2.x,P2.y), EPS);
assertEquals("P3", P3.z, plan.z(P3.x,P3.y), EPS);
final double[] x = new double[4000];
final double[] y = new double[4000];
final double[] z = new double[4000];
for (int i=0; i<z.length; i++) {
x[i] = 40 + 100*rd.nextDouble();
y[i] = 40 + 100*rd.nextDouble();
z[i] = plan.z(x[i], y[i]) + 10*rd.nextDouble()-5;
}
final Plane copy = plan.clone();
final double eps = 1E-2; // We do expect some difference, but not much more than that.
assertEquals("c", copy.c, plan.c, eps);
assertEquals("cx", copy.cx, plan.cx, eps);
assertEquals("cy", copy.cy, plan.cy, eps);
}
}