Exemplo n.º 1
0
  /**
   * Convert lat/lon coordinates to projection coordinates.
   *
   * @param from array of lat/lon coordinates: from[2][n], where from[0][i], from[1][i] is the
   *     (lat,lon) coordinate of the ith point
   * @param to resulting array of projection coordinates, where to[0][i], to[1][i] is the (x,y)
   *     coordinate of the ith point
   * @param latIndex index of latitude in "from"
   * @param lonIndex index of longitude in "from"
   * @return the "to" array.
   */
  public double[][] latLonToProj(double[][] from, double[][] to, int latIndex, int lonIndex) {
    int cnt = from[0].length;
    double[] fromLatA = from[latIndex];
    double[] fromLonA = from[lonIndex];
    double[] resultXA = to[INDEX_X];
    double[] resultYA = to[INDEX_Y];
    double toX, toY;

    for (int i = 0; i < cnt; i++) {
      double fromLat = fromLatA[i];
      double fromLon = fromLonA[i];

      fromLat = Math.toRadians(fromLat);
      double lonDiff = Math.toRadians(LatLonPointImpl.lonNormal(fromLon - lon0Degrees));
      double cosc = sinLat0 * Math.sin(fromLat) + cosLat0 * Math.cos(fromLat) * Math.cos(lonDiff);
      if (cosc >= 0) {
        toX = R * Math.cos(fromLat) * Math.sin(lonDiff);
        toY = R * (cosLat0 * Math.sin(fromLat) - sinLat0 * Math.cos(fromLat) * Math.cos(lonDiff));
      } else {
        toX = Double.POSITIVE_INFINITY;
        toY = Double.POSITIVE_INFINITY;
      }

      resultXA[i] = toX;
      resultYA[i] = toY;
    }
    return to;
  }
Exemplo n.º 2
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  /**
   * Convert projection coordinates to a LatLonPoint Note: a new object is not created on each call
   * for the return value.
   *
   * @param world convert from these projection coordinates
   * @param result the object to write to
   * @return LatLonPoint convert to these lat/lon coordinates
   */
  public LatLonPoint projToLatLon(ProjectionPoint world, LatLonPointImpl result) {
    double fromX = world.getX() - falseEasting;
    double fromY = world.getY() - falseNorthing;

    double toLon = Math.toDegrees(fromX / A) + lon0;

    double e = Math.exp(-fromY / A);
    double toLat = Math.toDegrees(Math.PI / 2 - 2 * Math.atan(e)); // Snyder p 44

    result.setLatitude(toLat);
    result.setLongitude(toLon);
    return result;
  }
Exemplo n.º 3
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  /**
   * Construct a Orthographic Projection, specify earth radius
   *
   * @param lat0 lat origin of the coord. system on the projection plane
   * @param lon0 lon origin of the coord. system on the projection plane
   * @param earthRadius radius of the earth
   * @throws IllegalArgumentException if lat0, par1, par2 = +/-90 deg
   */
  public Orthographic(double lat0, double lon0, double earthRadius) {
    super("Orthographic", false);

    this.lat0 = Math.toRadians(lat0);
    this.lon0 = Math.toRadians(lon0);
    R = earthRadius;

    precalculate();

    addParameter(CF.GRID_MAPPING_NAME, CF.ORTHOGRAPHIC);
    addParameter(CF.LATITUDE_OF_PROJECTION_ORIGIN, lat0);
    addParameter(CF.LONGITUDE_OF_PROJECTION_ORIGIN, lon0);
    addParameter(CF.EARTH_RADIUS, earthRadius * 1000);
  }
Exemplo n.º 4
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  /**
   * This returns true when the line between pt1 and pt2 crosses the seam. When the cone is
   * flattened, the "seam" is lon0 +- 180.
   *
   * @param pt1 point 1
   * @param pt2 point 2
   * @return true when the line between pt1 and pt2 crosses the seam.
   */
  public boolean crossSeam(ProjectionPoint pt1, ProjectionPoint pt2) {
    // either point is infinite
    if (ProjectionPointImpl.isInfinite(pt1) || ProjectionPointImpl.isInfinite(pt2)) return true;

    // opposite signed X values, larger then 5000 km
    return (pt1.getX() * pt2.getX() < 0) && (Math.abs(pt1.getX() - pt2.getX()) > 5000.0);
  }
Exemplo n.º 5
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  /**
   * Convert a LatLonPoint to projection coordinates
   *
   * @param latLon convert from these lat, lon coordinates
   * @param result the object to write to
   * @return the given result
   */
  public ProjectionPoint latLonToProj(LatLonPoint latLon, ProjectionPointImpl result) {
    double toX, toY;
    double fromLat = latLon.getLatitude();
    double fromLon = latLon.getLongitude();
    double fromLat_r = Math.toRadians(fromLat);

    // infinite projection
    if ((Math.abs(90.0 - Math.abs(fromLat))) < TOLERANCE) {
      toX = Double.POSITIVE_INFINITY;
      toY = Double.POSITIVE_INFINITY;
    } else {
      toX = A * Math.toRadians(LatLonPointImpl.range180(fromLon - this.lon0));
      toY = A * SpecialMathFunction.atanh(Math.sin(fromLat_r)); // p 41 Snyder
    }

    result.setLocation(toX + falseEasting, toY + falseNorthing);
    return result;
  }
Exemplo n.º 6
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  /**
   * Convert a LatLonPoint to projection coordinates
   *
   * @param latLon convert from these lat, lon coordinates
   * @param result the object to write to
   * @return the given result
   */
  public ProjectionPoint latLonToProj(LatLonPoint latLon, ProjectionPointImpl result) {
    double toX, toY;
    double fromLat = latLon.getLatitude();
    double fromLon = latLon.getLongitude();

    fromLat = Math.toRadians(fromLat);
    double lonDiff = Math.toRadians(LatLonPointImpl.lonNormal(fromLon - lon0Degrees));
    double cosc = sinLat0 * Math.sin(fromLat) + cosLat0 * Math.cos(fromLat) * Math.cos(lonDiff);
    if (cosc >= 0) {
      toX = R * Math.cos(fromLat) * Math.sin(lonDiff);
      toY = R * (cosLat0 * Math.sin(fromLat) - sinLat0 * Math.cos(fromLat) * Math.cos(lonDiff));
    } else {
      toX = Double.POSITIVE_INFINITY;
      toY = Double.POSITIVE_INFINITY;
    }

    result.setLocation(toX, toY);
    return result;
  }
Exemplo n.º 7
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  /**
   * Construct a Mercator Projection.
   *
   * @param lon0 longitude of origin (degrees)
   * @param par standard parallel (degrees). cylinder cuts earth at this latitude.
   * @param false_easting false_easting in km
   * @param false_northing false_northing in km
   * @param radius earth radius in km
   */
  public Mercator(
      double lon0, double par, double false_easting, double false_northing, double radius) {
    super("Mercator", false);

    this.lon0 = lon0;
    this.par = par;
    this.falseEasting = false_easting;
    this.falseNorthing = false_northing;
    this.earthRadius = radius;

    this.par_r = Math.toRadians(par);

    precalculate();

    addParameter(CF.GRID_MAPPING_NAME, CF.MERCATOR);
    addParameter(CF.LONGITUDE_OF_PROJECTION_ORIGIN, lon0);
    addParameter(CF.STANDARD_PARALLEL, par);
    addParameter(CF.EARTH_RADIUS, earthRadius * 1000);
    if ((false_easting != 0.0) || (false_northing != 0.0)) {
      addParameter(CF.FALSE_EASTING, false_easting);
      addParameter(CF.FALSE_NORTHING, false_northing);
      addParameter(CDM.UNITS, "km");
    }
  }
Exemplo n.º 8
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 /** Precalculate some params */
 private void precalculate() {
   A = earthRadius * Math.cos(par_r); // incorporates the scale factor at par
 }
 boolean close(double d1, double d2) {
   return Math.abs(d1 - d2) < TOLERENCE;
 }
Exemplo n.º 10
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  /**
   * Convert lat/lon coordinates to projection coordinates.
   *
   * @param from array of lat/lon coordinates: from[2][n], where (from[0][i], from[1][i]) is the
   *     (lat,lon) coordinate of the ith point
   * @param to resulting array of projection coordinates: to[2][n] where (to[0][i], to[1][i]) is the
   *     (x,y) coordinate of the ith point
   * @return the "to" array
   */
  public double[][] projToLatLon(double[][] from, double[][] to) {
    int cnt = from[0].length;
    double[] fromXA = from[INDEX_X];
    double[] fromYA = from[INDEX_Y];
    double[] toLatA = to[INDEX_LAT];
    double[] toLonA = to[INDEX_LON];

    double toLat, toLon;
    for (int i = 0; i < cnt; i++) {
      double fromX = fromXA[i];
      double fromY = fromYA[i];

      double rho = Math.sqrt(fromX * fromX + fromY * fromY);
      double c = Math.asin(rho / R);

      toLon = lon0;
      double temp = 0;
      if (Math.abs(rho) > TOLERANCE) {
        toLat = Math.asin(Math.cos(c) * sinLat0 + (fromY * Math.sin(c) * cosLat0 / rho));
        if (Math.abs(lat0 - PI_OVER_4) > TOLERANCE) { // not 90 or -90
          temp = rho * cosLat0 * Math.cos(c) - fromY * sinLat0 * Math.sin(c);
          toLon = lon0 + Math.atan(fromX * Math.sin(c) / temp);
        } else if (lat0 == PI_OVER_4) {
          toLon = lon0 + Math.atan(fromX / -fromY);
          temp = -fromY;
        } else {
          toLon = lon0 + Math.atan(fromX / fromY);
          temp = fromY;
        }
      } else {
        toLat = lat0;
      }
      toLat = Math.toDegrees(toLat);
      toLon = Math.toDegrees(toLon);
      if (temp < 0) {
        toLon += 180;
      }
      toLon = LatLonPointImpl.lonNormal(toLon);

      toLatA[i] = toLat;
      toLonA[i] = toLon;
    }
    return to;
  }
Exemplo n.º 11
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 /**
  * Get the origin longitude in degrees
  *
  * @return the origin longitude.
  */
 public double getOriginLon() {
   return Math.toDegrees(lon0);
 }
Exemplo n.º 12
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  /**
   * Convert projection coordinates to a LatLonPoint Note: a new object is not created on each call
   * for the return value.
   *
   * @param world convert from these projection coordinates
   * @param result the object to write to
   * @return LatLonPoint convert to these lat/lon coordinates
   */
  public LatLonPoint projToLatLon(ProjectionPoint world, LatLonPointImpl result) {
    double toLat, toLon;
    double fromX = world.getX();
    double fromY = world.getY();

    double rho = Math.sqrt(fromX * fromX + fromY * fromY);
    double c = Math.asin(rho / R);

    toLon = lon0;
    double temp = 0;
    if (Math.abs(rho) > TOLERANCE) {
      toLat = Math.asin(Math.cos(c) * sinLat0 + (fromY * Math.sin(c) * cosLat0 / rho));
      if (Math.abs(lat0 - PI_OVER_4) > TOLERANCE) { // not 90 or -90
        temp = rho * cosLat0 * Math.cos(c) - fromY * sinLat0 * Math.sin(c);
        toLon = lon0 + Math.atan(fromX * Math.sin(c) / temp);
      } else if (lat0 == PI_OVER_4) {
        toLon = lon0 + Math.atan(fromX / -fromY);
        temp = -fromY;
      } else {
        toLon = lon0 + Math.atan(fromX / fromY);
        temp = fromY;
      }
    } else {
      toLat = lat0;
    }
    toLat = Math.toDegrees(toLat);
    toLon = Math.toDegrees(toLon);
    if (temp < 0) {
      toLon += 180;
    }
    toLon = LatLonPointImpl.lonNormal(toLon);

    result.setLatitude(toLat);
    result.setLongitude(toLon);
    return result;
  }
Exemplo n.º 13
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 /**
  * Set the origin latitude.
  *
  * @param lat the origin latitude.
  */
 public void setOriginLat(double lat) {
   lat0 = Math.toRadians(lat);
   precalculate();
 }
Exemplo n.º 14
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 /**
  * Set the origin longitude.
  *
  * @param lon the origin longitude.
  */
 public void setOriginLon(double lon) {
   lon0 = Math.toRadians(lon);
   precalculate();
 }
Exemplo n.º 15
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 /**
  * Get the origin latitude in degrees
  *
  * @return the origin latitude.
  */
 public double getOriginLat() {
   return Math.toDegrees(lat0);
 }
Exemplo n.º 16
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 /**
  * Convert "scale at standard parellel" to "standard parellel"
  *
  * @param scale scale at standard parallel
  * @return standard parellel in degrees
  */
 public static double convertScaleToStandardParallel(double scale) {
   // k = 1 / cos (par); snyder p 44
   // par = arccos(1/k);
   double par = Math.acos(1.0 / scale);
   return Math.toDegrees(par);
 }
Exemplo n.º 17
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 /** Precalculate some stuff */
 private void precalculate() {
   sinLat0 = Math.sin(lat0);
   cosLat0 = Math.cos(lat0);
   lon0Degrees = Math.toDegrees(lon0);
 }