Class SkyDataGeom

java.lang.Object
uk.ac.starlink.ttools.plot2.geom.SkyDataGeom
All Implemented Interfaces:
DataGeom
public abstract class SkyDataGeom extends Object implements DataGeom
Defines positional data coordinates used by a sky plot.
Since:
20 Feb 2013
Author:
Mark Taylor

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final SkyDataGeom
    GENERIC
    Instance which converts between unspecified, but identical, systems.

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    SkyDataGeom(String variantName, SkySys viewSys)
    Constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    static SkyDataGeom
    createGeom(SkySys userSys, SkySys viewSys)
    Creates a data geom with input user data in one sky system and output data coordinates in another sky system.
    abstract boolean
    equals(Object other)
     
    int
    getDataDimCount()
    Returns 3.
    Coord[]
    getPosCoords()
    Returns the definitions for the user-supplied coordinates that indicate plot positions.
    String
    getVariantName()
    Returns a label for this DataGeom.
    SkySys
    getViewSystem()
    Returns the nominal sky coordinate system of this geom's view, if available.
    abstract int
    hashCode()
     
    boolean
    readDataPos(Tuple tuple, int ic, double[] dpos)
    Determines the positional coordinates in data space for a supplied tuple.
    abstract void
    rotate(double[] dpos)
    Rotates a 3-vector in place from this geom's data coordinate system to its view coordinate system.
    abstract void
    unrotate(double[] dpos)
    Rotates a 3-vector in place from this geom's view coordinate system to its data coordinate system.

    Methods inherited from class Object

    clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • GENERIC

      public static final SkyDataGeom GENERIC
      Instance which converts between unspecified, but identical, systems.

  • Constructor Details

    • SkyDataGeom

      protected SkyDataGeom(String variantName, SkySys viewSys)
      Constructor.
      Parameters:
      variantName - name for this data geom
      viewSys - nominal sky coordinate system of view; if unknown or not applicable, may be null

  • Method Details

    • getDataDimCount

      public int getDataDimCount()
      Returns 3.
      Specified by:
      getDataDimCount in interface DataGeom
      Returns:
      number of elements in data space coordinate array

    • getVariantName

      public String getVariantName()
      Description copied from interface: DataGeom
      Returns a label for this DataGeom. It may be used to distinguish from other geoms used in the same plot type, so for instance call it "Cartesian" or "Polar" rather than "Plane" if it's X,Y.
      Specified by:
      getVariantName in interface DataGeom
      Returns:
      user-directed input coordinate type name

    • getPosCoords

      public Coord[] getPosCoords()
      Description copied from interface: DataGeom
      Returns the definitions for the user-supplied coordinates that indicate plot positions.
      Specified by:
      getPosCoords in interface DataGeom
      Returns:
      coordinate quantity array for this geometry

    • readDataPos

      public boolean readDataPos(Tuple tuple, int ic, double[] dpos)
      Description copied from interface: DataGeom
      Determines the positional coordinates in data space for a supplied tuple.

      A parameter supplies the index of the field in the tuple at which the positional coordinate(s) can be found. Each position is represented by DataGeom.getPosCoords() columns of the tuple. By convention positions are at the start of the tuple, so if there is one position in the tuple it will be at icol=0, and there are multiple positions the N'th one will be at icol=N*getPosCoords().

      An array of (at least) DataGeom.getDataDimCount() elements is supplied, and on success the data space coordinate values are written into it.

      Specified by:
      readDataPos in interface DataGeom
      Parameters:
      tuple - coordinate tuple
      ic - column index in tuple at which the positional information starts
      dpos - array into which data space coordinates are written
      Returns:
      true iff conversion was successful

    • rotate

      public abstract void rotate(double[] dpos)
      Rotates a 3-vector in place from this geom's data coordinate system to its view coordinate system.
      Parameters:
      dpos - (x,y,z) vector to be rotated in place

    • unrotate

      public abstract void unrotate(double[] dpos)
      Rotates a 3-vector in place from this geom's view coordinate system to its data coordinate system.
      Parameters:
      dpos - (x,y,z) vector to be rotated in place

    • getViewSystem

      public SkySys getViewSystem()
      Returns the nominal sky coordinate system of this geom's view, if available.
      Returns:
      nominal sky view system, or null if not known or applicable

    • hashCode

      public abstract int hashCode()
      Overrides:
      hashCode in class Object

    • equals

      public abstract boolean equals(Object other)
      Overrides:
      equals in class Object

    • createGeom

      public static SkyDataGeom createGeom(SkySys userSys, SkySys viewSys)
      Creates a data geom with input user data in one sky system and output data coordinates in another sky system.
      Parameters:
      userSys - sky system in which user data is supplied
      viewSys - sky system in which the plot is viewed
      Returns:
      new data geom

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