Class HtmSkyPixellator

    • Constructor Summary

      Constructors 
      Constructor Description
      HtmSkyPixellator()
      Constructor.
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int calculateDefaultLevel​(double scale)
      Determines a default value to use for the level paramer based on a given scale.
      int getLevel()
      Returns the HTM level, which determines sky pixel size.
      java.lang.Object[] getPixels​(double alpha, double delta, double radius)
      Returns an array of objects representing pixels in a given region.
      double getScale()
      Returns the most recently set angular scale.
      DescribedValue getTuningParameter()
      Returns a parameter whose value may be adjusted to alter the pixellisation scale.
      void setLevel​(int level)
      Sets the HTM level value, which determines sky pixel size.
      void setScale​(double scale)
      Sets the characteristic angular scale for this pixellator.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • HtmSkyPixellator

        public HtmSkyPixellator()
        Constructor.
    • Method Detail

      • setScale

        public void setScale​(double scale)
        Description copied from interface: SkyPixellator
        Sets the characteristic angular scale for this pixellator. Pixels should be approximately the size given, so that a larger scale corresponds to larger pixel sizes. The details of pixel size are determined by the details of the pixellation scheme however.
        Specified by:
        setScale in interface SkyPixellator
        Parameters:
        scale - pixel length scale in radians
      • getScale

        public double getScale()
        Description copied from interface: SkyPixellator
        Returns the most recently set angular scale.
        Specified by:
        getScale in interface SkyPixellator
        Returns:
        pixel length scale in radians
      • getTuningParameter

        public DescribedValue getTuningParameter()
        Description copied from interface: SkyPixellator
        Returns a parameter whose value may be adjusted to alter the pixellisation scale. This is not necessarily the same as the scale attribute (its value need not be an angle).
        Specified by:
        getTuningParameter in interface SkyPixellator
        Returns:
        tuning parameter
      • getPixels

        public java.lang.Object[] getPixels​(double alpha,
                                            double delta,
                                            double radius)
        Description copied from interface: SkyPixellator
        Returns an array of objects representing pixels in a given region. The parameters specify a small circle on the sphere; any pixels which overlap this circle must be returned (additional pixels may also be returned). The output objects are of some opaque type, but must implement the equals and hashCode methods appropriately, so that objects returned from one call can be compared for identity with objects returned from a subsequent call. This comparability is only guaranteed to work if the pixel scale is not changed in between calls.
        Specified by:
        getPixels in interface SkyPixellator
        Parameters:
        alpha - right ascension of circle centre in radians
        delta - declination of circle centre in radians
        radius - radius of circle in radians
        Returns:
        array of opaque but comparable pixel objects
      • setLevel

        public void setLevel​(int level)
        Sets the HTM level value, which determines sky pixel size. May be in the range 0 (90deg) to 24 (0.01"). If set to -1, a suitable value will be used based on the scale.
        Parameters:
        level - new level value
      • getLevel

        public int getLevel()
        Returns the HTM level, which determines sky pixel size. The returned value may be the result of a default determination based on scale if no explicit level has been set hitherto, and a non-zero scale is available.
        Returns:
        level level value used by this engine
      • calculateDefaultLevel

        public int calculateDefaultLevel​(double scale)
        Determines a default value to use for the level paramer based on a given scale.
        Parameters:
        scale - sky distance scale angle, in radians