Examples with Position au.gov.amsa.util.navigation.Position used on opensource projects

Example 1 with Position

use of au.gov.amsa.util.navigation.Position in project risky by amsa-code.

the class DistanceTravelledCalculator method getCellDistances.

@VisibleForTesting
static final Observable<CellAndDistance> getCellDistances(final Position a, final Position b, final Options options) {
    return Observable.create(new OnSubscribe<CellAndDistance>() {

        @Override
        public void call(Subscriber<? super CellAndDistance> subscriber) {
            try {
                GridTraversor grid = new GridTraversor(options);
                boolean keepGoing = true;
                Position p1 = a;
                Position destination = b;
                int count = 0;
                while (keepGoing) {
                    Position p2 = grid.nextPoint(p1, destination);
                    double distanceNm = p1.getDistanceToKm(p2) / 1.852;
                    // report cell and distance
                    Optional<Cell> cell = Cell.cellAt(p1.getLat(), p1.getLon(), options);
                    if (cell.isPresent())
                        subscriber.onNext(new CellAndDistance(cell.get(), distanceNm));
                    keepGoing = p2.getLat() != destination.getLat() || p2.getLon() != destination.getLon();
                    keepGoing = keepGoing && !subscriber.isUnsubscribed();
                    p1 = p2;
                    count++;
                    checkCount(p1, destination, count, options);
                }
                subscriber.onCompleted();
            } catch (Throwable t) {
                // TODO resolve all problems so that this will revert to a
                // call to onError
                log.warn(t.getMessage(), t);
                subscriber.onCompleted();
            // subscriber.onError(t);
            }
        }
    });
}

Example 2 with Position

use of au.gov.amsa.util.navigation.Position in project risky by amsa-code.

the class GridTraversor method nextPointCrossingLatitude.

private Position nextPointCrossingLatitude(Position a, Position b, double leftLon, double rightLon, double targetLat, double bearingDegrees) {
    LongitudePair lonCrossingCandidates = a.getLongitudeOnGreatCircle(b, targetLat);
    if (lonCrossingCandidates != null) {
        double lonCrossing;
        // choose candidate closest in longitude to point a along path to b
        boolean candidate1ok = leftLon <= lonCrossingCandidates.getLon1() && lonCrossingCandidates.getLon1() <= rightLon && !(lonCrossingCandidates.getLon1() == a.getLon() && targetLat == a.getLat());
        boolean candidate2ok = leftLon <= lonCrossingCandidates.getLon2() && lonCrossingCandidates.getLon2() <= rightLon && !(lonCrossingCandidates.getLon2() == a.getLon() && targetLat == a.getLat());
        if (candidate1ok && candidate2ok) {
            // choose the best of the candidates
            // no units used in calculations because only doing comparisons
            // so don't care if it's km or nautical miles
            double distance1ToB = new Position(targetLat, lonCrossingCandidates.getLon1()).getDistanceToKm(b);
            double distance2ToB = new Position(targetLat, lonCrossingCandidates.getLon2()).getDistanceToKm(b);
            double distanceAToB = a.getDistanceToKm(b);
            if (distance1ToB > distanceAToB)
                candidate1ok = false;
            if (distance2ToB > distanceAToB)
                candidate2ok = false;
            if (candidate1ok && candidate2ok) {
                if (distance1ToB < distance2ToB) {
                    candidate1ok = false;
                } else
                    candidate2ok = false;
            }
            if (candidate1ok)
                lonCrossing = lonCrossingCandidates.getLon1();
            else if (candidate2ok)
                lonCrossing = lonCrossingCandidates.getLon2();
            else
                // neither of the candidates are on the way to b!
                return null;
        } else if (candidate1ok) {
            lonCrossing = lonCrossingCandidates.getLon1();
        } else if (candidate2ok)
            lonCrossing = lonCrossingCandidates.getLon2();
        else
            return null;
        // check that lonCrossing is on the segment a to b
        double bearingDegreesTest = bearingDegrees(a, Position.create(targetLat, lonCrossing));
        double diff = Position.getBearingDifferenceDegrees(bearingDegrees, bearingDegreesTest);
        if (Math.abs(diff) > 90)
            return null;
        return Position.create(targetLat, lonCrossing);
    } else
        return null;
}

Example 3 with Position

use of au.gov.amsa.util.navigation.Position in project risky by amsa-code.

the class GridTraversorTest method testGridNextPointOnBottomEdgeStartingInsideCell.

/**
 **********************************************************************
 * Test going from (-30.8,140.2) to (-31.7,142.6) on a single degree grid
 * and back again!
 ***********************************************************************
 */
@Test
public void testGridNextPointOnBottomEdgeStartingInsideCell() {
    GridTraversor grid = createGrid();
    Position a = Position.create(-30.8, 140.2);
    Position b = Position.create(-31.7, 142.6);
    assertEquals(114.303575, a.getBearingDegrees(b), PRECISION);
    Position p = grid.nextPoint(a, b);
    assertEquals(-31, p.getLat(), PRECISION);
    assertEquals(140.719351, p.getLon(), PRECISION);
}

Example 4 with Position

use of au.gov.amsa.util.navigation.Position in project risky by amsa-code.

the class GridTraversorTest method testGridNextPointOnDestinationStartingBottomEdge.

@Test
public void testGridNextPointOnDestinationStartingBottomEdge() {
    GridTraversor grid = createGrid();
    Position a = Position.create(-31.7, 142.6);
    Position b = Position.create(-30.8, 140.2);
    Position p = grid.nextPoint(a, b);
    Position p2 = grid.nextPoint(p, b);
    Position p3 = grid.nextPoint(p2, b);
    System.out.println("p3lat=" + p3.getLat());
    Position p4 = grid.nextPoint(p3, b);
    assertEquals(-30.8, p4.getLat(), PRECISION);
    assertEquals(140.2, p4.getLon(), PRECISION);
}

Example 5 with Position

use of au.gov.amsa.util.navigation.Position in project risky by amsa-code.

the class GridTraversorTest method testGridNextPointOnRightEdgeStartingLeftEdge.

@Test
public void testGridNextPointOnRightEdgeStartingLeftEdge() {
    GridTraversor grid = createGrid();
    Position a = Position.create(-30.8, 140.2);
    Position b = Position.create(-31.7, 142.6);
    Position p = grid.nextPoint(a, b);
    Position p2 = grid.nextPoint(p, b);
    Position p3 = grid.nextPoint(p2, b);
    assertEquals(-31.480781, p3.getLat(), PRECISION);
    assertEquals(142.0, p3.getLon(), PRECISION);
}