HalfTrackSpanHandler.java
- /* Copyright 2002-2024 CS GROUP
- * Licensed to CS GROUP (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,
- * 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.orekit.models.earth.tessellation;
- import org.hipparchus.ode.events.Action;
- import org.orekit.propagation.SpacecraftState;
- import org.orekit.propagation.events.EventDetector;
- import org.orekit.propagation.events.handlers.EventHandler;
- import org.orekit.time.AbsoluteDate;
- /** Event handler for half track span.
- * @since 7.1
- * @see AlongTrackAiming
- * @author Luc Maisonobe
- */
- class HalfTrackSpanHandler implements EventHandler {
- /** Indicator for zone tiling with respect to ascending or descending orbits. */
- private final boolean isAscending;
- /** Halftrack start date. */
- private AbsoluteDate start;
- /** Halftrack end date. */
- private AbsoluteDate end;
- /** Simple constructor.
- * @param isAscending indicator for zone tiling with respect to ascending
- * or descending orbits
- */
- HalfTrackSpanHandler(final boolean isAscending) {
- this.isAscending = isAscending;
- this.start = null;
- this.end = null;
- }
- /** Get the start date of the half track.
- * @return start date of the half track
- */
- public AbsoluteDate getStart() {
- return start;
- }
- /** Get the end date of the half track.
- * @return end date of the half track
- */
- public AbsoluteDate getEnd() {
- return end;
- }
- /** {@inheritDoc} */
- @Override
- public Action eventOccurred(final SpacecraftState s, final EventDetector detector, final boolean increasing) {
- if (increasing ^ isAscending) {
- // we have found an end event
- if (start == null) {
- // we don't have the start event yet,
- // so we ignore this and wait for the next orbit
- return Action.CONTINUE;
- } else {
- end = s.getDate();
- return Action.STOP;
- }
- } else {
- // we have found the start of the span
- start = s.getDate();
- return Action.CONTINUE;
- }
- }
- }