gentoo-overlay/dev-python/pymoc/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
  <maintainer type="project">
    <email>sci-astronomy@gentoo.org</email>
    <name>Gentoo Astronomy Project</name>
  </maintainer>
  <longdescription lang="en">
    Frequently astronomical survey catalogues or images are sparse and
    cover only a small part of the sky.  In a Multi-Order Coverage map
    the extent of data in a particular dataset is cached as a
    pre-calculated mask image.  The hierarchical nature enables fast
    boolean operations in image space, without needing to perform complex
    geometrical calculations.  Services such as VizieR generally offer the
    MOC masks, allowing a faster experience in graphical applications
    such as Aladin, or for researchers quickly needing to locate which
    datasets may contain overlapping coverage.

    The MOC mask image itself is tessellated and stored in NASA HealPix
    format, encoded inside a FITS image container.  Using the HealPix
    (Hierarchical Equal Area isoLatitude Pixelization) tessellation
    method ensures that more precision (pixels) in the mask are available
    when describing complex shapes such as approximating survey or
    polygon edges, while only needing to store a single big cell/pixel
    when an coverage is either completely inside, or outside of the mask.
    Catalogues can be rendered on the mask as circles.
  </longdescription>
  <upstream>
    <remote-id type="pypi">pymoc</remote-id>
    <remote-id type="github">grahambell/pymoc</remote-id>
  </upstream>
</pkgmetadata>