Package com.luciad.projection

Class TLcdCassini

java.lang.Object
com.luciad.projection.ALcdProjection
com.luciad.projection.ALcdTransverseCylindrical
com.luciad.projection.TLcdCassini
All Implemented Interfaces:
ILcdProjection, ILcdTransverseCylindrical, ILcdPropertyChangeSource, Serializable, Cloneable
Direct Known Subclasses:
TLcdCassiniSoldner
public class TLcdCassini extends ALcdTransverseCylindrical
Cassini projection.

Introduction

The Cassini projection is the transverse aspect of the equidistant cylindrical projection. The globe is first rotated so the central meridian becomes the "equator", and then the normal equidistant cylindrical projection is applied.

Properties

  • Neither equal-area nor conformal.
  • The central meridian, each meridian 90° from the central meridian and the Equator are shown as straight lines.
  • Other meridians and parallels are complex curves.
  • Scale is true along the central meridian and lines perpendicular to it.
  • Scale is constant but not true along lines other meridians.

Example

Sample code


 ILcdProjection projection =
     new TLcdCassini(-40.0);

Implementation aspects

The equations of the cassini projection are taken from [Snyder1987].

Limitations

Only the spherical form is implemented. See TLcdCassiniSoldner for an ellipsoidal version of this projection.

See Also:

  • Constructor Details

    • TLcdCassini

      public TLcdCassini()
      Constructs a Cassini projection with the point of origin at (0,0).

    • TLcdCassini

      public TLcdCassini(double aCentralMeridian)
      Constructs a Cassini projection with the given central meridian and the origin latitude at the equator.
      Parameters:
      aCentralMeridian - the central meridian of the projection.

    • TLcdCassini

      public TLcdCassini(double aCentralMeridian, double aOriginLat)
      Constructs a Cassini projection with the given central meridian and origin latitude.
      Parameters:
      aCentralMeridian - the central meridian of the projection.
      aOriginLat - the latitude of the point of origin of the projection.

  • Method Details

    • lonlatheight2worldOnSphereSFCT

      public void lonlatheight2worldOnSphereSFCT(ILcdPoint aLLP, double aRadius, ILcd2DEditablePoint aXYPointSFCT) throws TLcdOutOfBoundsException
      Description copied from interface: ILcdProjection
      Transforms an ILcd2DEditablePoint on a sphere into the cartesian coordinate system of the projection.
      Parameters:
      aLLP - point to be projected.
      aRadius - radius of the sphere (meters).
      aXYPointSFCT - projected point as side effect.
      Throws:
      TLcdOutOfBoundsException - If the ILcdPoint aLLHP is not within the valid area of the projection (visible area), then this exception is thrown.

    • world2lonlatOnSphereSFCT

      public void world2lonlatOnSphereSFCT(ILcdPoint aXYPoint, double aRadius, ILcd2DEditablePoint aLLPSFCT) throws TLcdOutOfBoundsException
      Description copied from interface: ILcdProjection
      Transforms an ILcdPoint from the cartesian coordinate system of the projection into an ILcd2DEditablePoint onto a sphere.
      Parameters:
      aXYPoint - projected point for which the corresponding geodetic point is sought.
      aRadius - radius of the sphere (meters).
      aLLPSFCT - resulting geodetic coordinate as side effect.
      Throws:
      TLcdOutOfBoundsException - If the ILcdPoint aXYPoint is not within the valid area of the projection (visible area), then this exception is thrown.

    • isAllInBounds

      public boolean isAllInBounds()
      Description copied from interface: ILcdProjection
      If all geodetic coordinates (l ,j ) are projected (visible) by an ILcdProjection and all (x,y ) coordinates are bounded this is true. All ILcdProjection objects have bounded (x,y ) coordinates because the projection is cut off if necessary.
      Returns:
      true if all LonLatPoints are within the bounds of the projection, false otherwise.

    • isContinuous

      public boolean isContinuous()
      Description copied from interface: ILcdProjection
      An ILcdProjection is continuous if there are no interruptions in the world coordinates. Most projections are continuous.
      Specified by:
      isContinuous in interface ILcdProjection
      Overrides:
      isContinuous in class ALcdTransverseCylindrical
      Returns:
      true if the projection is continuous, false otherwise.

    • inLonLatBounds

      public boolean inLonLatBounds(ILcdPoint aLLP)
      Description copied from interface: ILcdProjection
      Checks if an ILcdPoint is inside the valid area of geodetic coordinates of the projection. The valid area is determined by the LonLatPoints that are visible and for which the corresponding cartesian coordinate is within the boundaries.
      Parameters:
      aLLP - ILcdPoint to be checked upon.
      Returns:
      true if valid, false if invalid.

    • boundaryLons

      public double[][] boundaryLons(double lat)
      Description copied from class: ALcdProjection
      Default implementation. To be redefined for specific projections.
      Specified by:
      boundaryLons in interface ILcdProjection
      Overrides:
      boundaryLons in class ALcdProjection
      Parameters:
      lat - latitude in decimal degrees and -90.0 <= aLat<= 90.0.
      Returns:
      the array of pairs of longitudes[0] and longitudes[1], where the closed interval longitudes[0] -> longitudes[1] is in visible area and -180.0 <= lon[i] <= 180.0.

    • boundaryLats

      public double[][] boundaryLats(double lon)
      Description copied from class: ALcdProjection
      Default implementation. To be redefined for specific projections.
      Specified by:
      boundaryLats in interface ILcdProjection
      Overrides:
      boundaryLats in class ALcdProjection
      Parameters:
      lon - longitude in decimal degrees -180.0 <= lon <= 180.0 .
      Returns:
      the array of pairs of latitudes lats[0] and lats[1], where the closed interval lats[0] -> lats[1] is in visible area and -90.0 <= lats[i] <= 90.0 .

    • world2DEditableBoundsOnSphereSFCT

      public void world2DEditableBoundsOnSphereSFCT(double aRadius, ILcd2DEditableBounds aWorldBounds)
      Description copied from interface: ILcdProjection
      Sets the ILcd2DEditableBounds object to the bounds of the projection in world coordinates.
      Parameters:
      aRadius - radius of the sphere.
      aWorldBounds - the bounds of the projection in world coordinates as side effect.

    • inWorldBoundsOnSphere

      public boolean inWorldBoundsOnSphere(ILcdPoint aXYPoint, double aRadius)
      Description copied from interface: ILcdProjection
      Checks if a ILcdPoint is inside the valid cartesian area of the projection. The valid cartesian area is determined naturally by the projection bounds or by an artificial introduced boundary limit because some cartesian points are at infinity. The shape of the valid cartesian area is in many cases rectangular or circular although it might be more complex.
      Parameters:
      aXYPoint - point to be checked upon.
      aRadius - radius of the sphere.
      Returns:
      true if valid, false if invalid.

    • toString

      public String toString()
      Returns the String representation of the Cassini projection.
      Specified by:
      toString in interface ILcdProjection
      Overrides:
      toString in class Object
      Returns:
      the String representation of the Cassini projection.