Field Detail

• AIT

  public static final SkyviewProjection AIT

  Aitoff projection.

• CAR1

  public static final SkyviewProjection CAR1

  Cartesian projection.

• TAN

  public static final SkyviewProjection TAN

  Gnomonic projection.

Constructor Detail

• SkyviewProjection

  public SkyviewProjection​(skyview.geometry.Projecter projecter,
                           java.awt.Shape shape,
                           boolean isContinuous)

  Constructor. You have to tell it whether the projection is known to be continuous. In more recent SkyView releases, I think this can be determined programmatically from the Projecter instance by using the function !projecter.straddleable().

  Parameters:

  projecter - projecter object

  shape - shape of the sky in this projection

  isContinuous - whether projection is known to be continuous

Method Detail

• getProjectionName

  public java.lang.String getProjectionName()

  Description copied from interface: Projection
  Returns the projection name.

  Specified by:

  getProjectionName in interface Projection

  Returns:

  user-directed projection name

• getProjectionDescription

  public java.lang.String getProjectionDescription()

  Description copied from interface: Projection
  Returns a short description of the projection. return projection description

  Specified by:

  getProjectionDescription in interface Projection

• getProjectionShape

  public java.awt.Shape getProjectionShape()

  Description copied from interface: Projection
  Returns the shape which encloses all the plane positions to which legal sky coordinates can be projected. Typically this has linear dimensions of the order of PI.

  Specified by:

  getProjectionShape in interface Projection

  Returns:

  projected sky shape

• isContinuous

  public boolean isContinuous()

  Description copied from interface: Projection
  Indicates whether this projection is known to be continous over its whole range. Returns false if there may be any cases for which small changes in the 3-vector leads to large changes in the plane position (such as near lon=180 in an Aitoff, but not a Sinus, projection).

  Specified by:

  isContinuous in interface Projection

  Returns:

  true iff this projection is known to be continuous

• project

  public boolean project​(double rx,
                         double ry,
                         double rz,
                         java.awt.geom.Point2D.Double pos)

  Description copied from interface: Projection
  Transforms a sky position to a plane position.

  Specified by:

  project in interface Projection

  Parameters:

  rx - normalised 3D X coordinate

  ry - normalised 3D Y coordinate

  rz - normalised 3D Z coordinate

  pos - point object into which projected dimensionless X,Y coordinates will be written on success

  Returns:

  true if transformation succeeded

• unproject

  public boolean unproject​(java.awt.geom.Point2D.Double pos,
                           double[] r3)

  Description copied from interface: Projection
  Transforms a plane position to a sky position.

  Specified by:

  unproject in interface Projection

  Parameters:

  pos - contains dimensionless X,Y coordinates of plane position

  r3 - 3-element array into which normalised X,Y,Z sky coordinates will be written on success

  Returns:

  true if transformation succeeded

• cursorRotate

  public double[] cursorRotate​(double[] rotmat,
                               java.awt.geom.Point2D.Double pos0,
                               java.awt.geom.Point2D.Double pos1)

  Returns null - rotation not implemented.

  Specified by:

  cursorRotate in interface Projection

  Parameters:

  rotmat - initial rotation matrix

  pos0 - initial cursor position

  pos1 - destination cursor position

  Returns:

  destination rotation matrix, or null

• projRotate

  public double[] projRotate​(double[] rotmat,
                             java.awt.geom.Point2D.Double pos0,
                             java.awt.geom.Point2D.Double pos1)

  Returns null - rotation not implemented.

  Specified by:

  projRotate in interface Projection

  Parameters:

  rotmat - initial rotation matrix

  pos0 - initial projected position

  pos1 - destination projected position

  Returns:

  destination rotation matrix, or null

• useRanges

  public boolean useRanges​(boolean reflect,
                           double[] r3,
                           double radiusRad)

  Returns false - ranging not used.

  Specified by:

  useRanges in interface Projection

  Parameters:

  reflect - whether requested aspect will be reflected

  r3 - central position of field of view (may be null)

  radiusRad - radius of field of view (may be NaN)

  Returns:

  true if ranges would be useful given the other arguments

  See Also:

  SurfaceFactory.readRanges(P, uk.ac.starlink.ttools.plot2.PlotLayer[], uk.ac.starlink.ttools.plot2.data.DataStore)

• createAspect

  public SkyAspect createAspect​(boolean reflect,
                                double[] r3,
                                double radiusRad,
                                Range[] ranges)

  Description copied from interface: Projection
  Creates a SkyAspect from configuration information. Either the supplied field of view or data ranges may be used, or neither.

  Specified by:

  createAspect in interface Projection

  Parameters:

  reflect - whether requested aspect will be reflected

  r3 - central position of field of view (may be null)

  radiusRad - radius of field of view (may be NaN)

  ranges - definite ranges for normalised X,Y,Z coordinates acquired from data

  Returns:

  new sky aspect

  See Also:

  SurfaceFactory.createAspect(P, uk.ac.starlink.ttools.plot2.config.ConfigMap, uk.ac.starlink.ttools.plot.Range[])

• getFov

  public SkyFov getFov​(SkySurface surf)

  Description copied from interface: Projection
  Returns the field of view represented by this aspect. This is a best estimate, it may be approximate depending on the projection geometry. If the field of view is the default for this projection, then null should be returned. Null may also be returned if for some reason no field of view can be determined.

  Specified by:

  getFov in interface Projection

  Parameters:

  surf - sky surface, which must be set up using this projection

  Returns:

  field of view, or null

• getSkyviewProjecter

  public skyview.geometry.Projecter getSkyviewProjecter()

  Returns the projecter object used by this SkyviewProjection.

  Returns:

  projecter

• createProjection

  public static SkyviewProjection createProjection​(skyview.geometry.Projecter projecter,
                                                   boolean isContinuous)

  Factory method that knows shapes for some projections. Name and description are taken from the skyview metadata.

  Parameters:

  projecter - skyview projecter

  isContinuous - whether projection is known to be continuous

  Throws:

  java.lang.IllegalArgumentException - if the shape is not known