ConstantAzimuthAiming.java
/* Copyright 2002-2019 CS Systèmes d'Information
* Licensed to CS Systèmes d'Information (CS) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* CS 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,
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package org.orekit.models.earth.tessellation;
import org.hipparchus.geometry.euclidean.threed.Vector3D;
import org.hipparchus.util.FastMath;
import org.orekit.bodies.GeodeticPoint;
import org.orekit.bodies.OneAxisEllipsoid;
/** Class used to orient tiles with respect to a geographic azimuth.
* @see AlongTrackAiming
* @author Luc Maisonobe
*/
public class ConstantAzimuthAiming implements TileAiming {
/** Cosine of the azimuth. */
private final double cos;
/** Sine of the azimuth. */
private final double sin;
/** Simple constructor.
* @param ellipsoid ellipsoid body on which the zone is defined
* @param azimuth geographic azimuth of the tiles
*/
public ConstantAzimuthAiming(final OneAxisEllipsoid ellipsoid, final double azimuth) {
this.cos = FastMath.cos(azimuth);
this.sin = FastMath.sin(azimuth);
}
/** {@inheritDoc} */
@Override
public Vector3D alongTileDirection(final Vector3D point, final GeodeticPoint gp) {
// compute the horizontal direction at fixed azimuth
return new Vector3D(cos, gp.getNorth(), sin, gp.getEast());
}
}