Class DivertedSingularityAiming
- java.lang.Object
-
- org.orekit.models.earth.tessellation.DivertedSingularityAiming
-
- All Implemented Interfaces:
TileAiming
public class DivertedSingularityAiming extends Object implements TileAiming
Class used to orient tiles such that there are no singularities within the zone of interest.This class is mainly useful for
sampling
a zone on ground when the grid directions is not really important and when the zone contains the pole, which is a singular point for bothConstantAzimuthAiming
andAlongTrackAiming
.- Author:
- Luc Maisonobe
- See Also:
AlongTrackAiming
,ConstantAzimuthAiming
-
-
Constructor Summary
Constructors Constructor Description DivertedSingularityAiming(SphericalPolygonsSet forbiddenZone)
Simple constructor.
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description Vector3D
alongTileDirection(Vector3D point, GeodeticPoint gp)
Find the along tile direction for tessellation at specified point.List<GeodeticPoint>
getSingularPoints()
Get points at which aiming direction cannot be computed.
-
-
-
Constructor Detail
-
DivertedSingularityAiming
public DivertedSingularityAiming(SphericalPolygonsSet forbiddenZone)
Simple constructor.- Parameters:
forbiddenZone
- zone out of which singularity should be diverted
-
-
Method Detail
-
getSingularPoints
public List<GeodeticPoint> getSingularPoints()
Get points at which aiming direction cannot be computed.As per Brouwer's hairy ball theorem, any vector field on the 2-sphere has at least one zero. This implies that any implementation of this interface has at least one point where the aiming direction cannot be computed. The most typical example is aiming always towards North pole, for which both poles are singular points.
- Specified by:
getSingularPoints
in interfaceTileAiming
- Returns:
- a non-empty (as per hairy ball theorem) list of points where aiming direction is either zero or cannot be computed
-
alongTileDirection
public Vector3D alongTileDirection(Vector3D point, GeodeticPoint gp)
Find the along tile direction for tessellation at specified point.- Specified by:
alongTileDirection
in interfaceTileAiming
- Parameters:
point
- point on the ellipsoid (Cartesian coordinates)gp
- point on the ellipsoid (geodetic coordinates)- Returns:
- normalized along tile direction
-
-