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AST_GETREGIONMESH - Return a mesh of points covering the surface or volume of a Region

Description:
This routine returns the axis values at a mesh of points either covering the surface (i.e. boundary) of the supplied Region, or filling the interior (i.e. volume) of the Region. The number of points in the mesh is approximately equal to the MeshSize attribute.
Invocation:
CALL AST_GETREGIONMESH( THIS, SURFACE, MAXPOINT, MAXCOORD, NPOINT, POINTS, STATUS )
Arguments:
THIS = INTEGER (Given)
Pointer to the Region.
SURFACE = LOGICAL (Given)
If .TRUE., the returned points will cover the surface or the Region. Otherwise, they will fill the interior of the Region.
MAXPOINT = INTEGER (Given)
If zero, the number of points in the mesh is returned in NPOINT, but no axis values are returned and all other parameters are ignored. If not zero, the supplied value should be the length of the first dimension of the POINTS array. An error is reported if the number of points in the mesh exceeds this number.
MAXCOORD = INTEGER (Given)
The length of the second dimension of the POINTS array. An error is reported if the number of axes in the supplied Region exceeds this number.
NPOINT = INTEGER (Returned)
The number of points in the returned mesh.
POINTS( MAXPOINT, MAXCOORD ) = DOUBLE PRECISION (Returned)
An array in which to return the coordinates values at the mesh positions. These are stored such that the value of coordinate number COORD for point number POINT is found in element POINTS(POINT,COORD).
STATUS = INTEGER (Given and Returned)
The global status.
Notes:
  • If the coordinate system represented by the Region has been changed since it was first created, the returned axis values refer to the new (changed) coordinate system, rather than the original coordinate system. Note however that if the transformation from original to new coordinate system is non-linear, the shape within the new coordinate system may be distorted, and so may not match that implied by the name of the Region subclass (Circle, Box, etc).


next up previous 264
Next: AST_GETREGIONPOINTS - Returns the positions that define the given Region
Up: AST Routine Descriptions
Previous: AST_GETREGIONFRAME - Obtain a pointer to the encapsulated Frame within a Region

AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council