14.11  The Guide_anyshape_r McStas Component

Reflecting surface (guide and mirror) with any shape, defined from an OFF file and a patch to allow m-, alpha- and W-values added per polygon face. Derived from Guide_anyshape / Guide_anyshape_r .

Identification

• Author: Emmanuel Farhi, adapted by Peter Link and Gaetano Mangiapia

• Origin: ILL/MLZ

• Date: August 4th 2010

Description

This is a reflecting object component, derived from Guide_anyshape. Its shape, as well as m-, alpha- and W-values (IN THIS ORDER) for each face, are defined from an OFF file, given with its file name. The object size is set as given from the file, where dimensions should be in meters. The bounding box may be re-scaled by specifying xwidth,yheight,zdepth parameters. The object may optionally be centered when using ’center=1’.

If in input only the values of R0 and Qc are specified, leaving m, alpha and W all null, then Guide_anyshape_g will use the values of these last three parameters that are specified in the OFF file for each face: floating point based values may be provided for them. In case at least one among m, alpha and W is not null, then Guide_anyshape_g will use these values as input (common for all the faces), ignoring those specified in the OFF file

The complex OFF/PLY geometry option handles any closed non-convex polyhedra. It supports the OFF and NOFF file format but not COFF (colored faces). Standard .OFF files may be generated from XYZ data using: qhull < coordinates.xyz Qx Qv Tv o > geomview.off or powercrust coordinates.xyz and viewed with geomview or java -jar jroff.jar (see below). The default size of the object depends of the OFF file data, but its bounding box may be resized using xwidth,yheight and zdepth. PLY geometry files are also supported.

Input parameters

Parameters in boldface are required; the others are optional.

Links

• Component source code found in file Guide_anyshape_r.comp.

• Geomview and Object File Format (OFF)

• Java version of Geomview (display only) jroff.jar

• qhull

• powercrust