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A Library for Handling
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Description:
This function returns a pointer to a new
Polygon that contains a subset
of the vertices in the supplied Polygon. The subset is chosen so that the
returned Polygon is a good approximation to the supplied Polygon, within the
limits specified by the supplied parameter values. That is, the density of
points in the returned Polygon is greater at points where the curvature of
the boundary of the supplied Polygon is greater.
Synopsis
AstPolygon
$\ast $astDownsize(
AstPolygon $\ast $this,
double maxerr, int maxvert )
Parameters:
this
Pointer to the Polygon.
maxerr
The maximum allowed discrepancy between the supplied and returned Polygons, expressed
as a geodesic distance within the Polygon’
s coordinate frame. If this is zero or less,
the returned Polygon will have the number of vertices specified by maxvert.
maxvert
The maximum allowed number of vertices in the returned Polygon. If
this is less than 3, the number of vertices in the returned Polygon will be
the minimum needed to achieve the maximum discrepancy specified by maxerr.
Returned Value
astDownsize()
Pointer to the new Polygon.
Notes:
Copyright (C) 2019 East Asian Observatory
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- AST
A Library for Handling
World
Coordinate Systems
in Astronomy - Next→
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