HaloXZPlaneCrossingDetector.java

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 * this work for additional information regarding copyright ownership.
 * CS licenses this file to You under the Apache License, Version 2.0
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 *   http://www.apache.org/licenses/LICENSE-2.0
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package org.orekit.propagation.events;

import org.orekit.propagation.SpacecraftState;
import org.orekit.propagation.events.handlers.EventHandler;
import org.orekit.propagation.events.handlers.StopOnIncreasing;

/** Detector for XZ Plane crossing.
 * @author Vincent Mouraux
 * @since 10.2
 */
public class HaloXZPlaneCrossingDetector extends AbstractDetector<HaloXZPlaneCrossingDetector> {

    /**
     * Simple Constructor.
     * @param maxCheck maximum checking interval (s)
     * @param threshold convergence threshold (s)
     */
    public HaloXZPlaneCrossingDetector(final double maxCheck, final double threshold) {
        this(new EventDetectionSettings(maxCheck, threshold, DEFAULT_MAX_ITER), new StopOnIncreasing());
    }

    /**
     * Protected constructor with full parameters.
     * <p>
     * This constructor is not public as users are expected to use the builder API
     * with the various {@code withXxx()} methods to set up the instance in a
     * readable manner without using a huge amount of parameters.
     * </p>
     * @param detectionSettings event detection settings
     * @param handler event handler to call at event occurrences
     * @since 13.0
     */
    protected HaloXZPlaneCrossingDetector(final EventDetectionSettings detectionSettings,
                                          final EventHandler handler) {
        super(detectionSettings, handler);
    }

    /** {@inheritDoc} */
    @Override
    protected HaloXZPlaneCrossingDetector create(final EventDetectionSettings detectionSettings,
                                                 final EventHandler newHandler) {
        return new HaloXZPlaneCrossingDetector(detectionSettings, newHandler);
    }

    /** Compute the value of the detection function.
     * @param s the current state information: date, kinematics, attitude
     * @return Position on Y axis
     */
    public double g(final SpacecraftState s) {
        return s.getPosition().getY();
    }

}