lucene/spatial3d/src/test/org/apache/lucene/spatial3d/geom/PlaneTest.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.lucene.spatial3d.geom;

import org.junit.Test;

import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.assertEquals;

/**
 * Test basic plane functionality.
 */
public class PlaneTest {

  @Test
  public void testIdenticalPlanes() {
    final GeoPoint p = new GeoPoint(PlanetModel.SPHERE, 0.123, -0.456);
    final Plane plane1 = new Plane(p, 0.0);
    final Plane plane2 = new Plane(p, 0.0);
    assertTrue(plane1.isNumericallyIdentical(plane2));
    final Plane plane3 = new Plane(p, 0.1);
    assertFalse(plane1.isNumericallyIdentical(plane3));
    final Vector v1 = new Vector(0.1, -0.732, 0.9);
    final double constant = 0.432;
    final Vector v2 = new Vector(v1.x * constant, v1.y * constant, v1.z * constant);
    final Plane p1 = new Plane(v1, 0.2);
    final Plane p2 = new Plane(v2, 0.2 * constant);
    assertTrue(p1.isNumericallyIdentical(p2));
  }

  @Test
  public void testIdenticalVector() {
    final Vector v1  = new Vector(1, 0 , 0);
    final Vector v2  = new Vector(1, 0 , 0);
    final Vector v3  = new Vector(-1, 0 , 0);
    assertTrue(v1.isNumericallyIdentical(v2));
    assertFalse(v1.isNumericallyIdentical(v3));
  }

  @Test
  public void testInterpolation() {
    // [X=0.35168818443386646, Y=-0.19637966197066342, Z=0.9152870857244183],
    // [X=0.5003343189532654, Y=0.522128543226148, Z=0.6906861469771293],

    final GeoPoint start = new GeoPoint(0.35168818443386646, -0.19637966197066342, 0.9152870857244183);
    final GeoPoint end = new GeoPoint(0.5003343189532654, 0.522128543226148, 0.6906861469771293);

    // [A=-0.6135342247741855, B=0.21504338363863665, C=0.28188192383666794, D=0.0, side=-1.0] internal? false;
    final Plane p = new Plane(-0.6135342247741855, 0.21504338363863665, 0.28188192383666794, 0.0);

    final GeoPoint[] points = p.interpolate(PlanetModel.SPHERE, start, end, new double[]{0.25, 0.50, 0.75});

    for (GeoPoint point : points) {
      assertTrue(p.evaluateIsZero(point));
    }
  }
  
  @Test
  public void testFindArcPoints() {
    // Create two points
    final GeoPoint p1 = new GeoPoint(PlanetModel.WGS84, 0.123, -0.456);
    final GeoPoint p2 = new GeoPoint(PlanetModel.WGS84, -0.368, 0.888);
    // Create a plane that links them.
    final Plane plane = new Plane(p1, p2);
    // Now, use that plane to find points that are a certain distance from the original
    final GeoPoint[] newPoints = plane.findArcDistancePoints(PlanetModel.WGS84, 0.20, p1);
    assertTrue(newPoints.length == 2);
    assertTrue(plane.evaluateIsZero(newPoints[0]));
    assertTrue(plane.evaluateIsZero(newPoints[1]));
    assertTrue(PlanetModel.WGS84.pointOnSurface(newPoints[0]));
    assertTrue(PlanetModel.WGS84.pointOnSurface(newPoints[1]));
    assertEquals(0.20, p1.arcDistance(newPoints[0]), 1e-6);
    assertEquals(0.20, p1.arcDistance(newPoints[1]), 1e-6);
  }
  
}