[ Identification | Description | Input parameters | Links ]

The Shape Component

A geometric shape without effect on neutron, for instrument display purpose.

Identification

• Site:
• Author: E. Farhi
• Origin: ILL
• Date: June 23rd 2009

Description

An inactive geometrical shape, for drawing purposes only.
It does not propagate neutron, nor interact.
Shape:
Geometric shape may be a cylinder, a sphere, a box or any other shape
box/plate:       xwidth x yheight x zdepth (thickness=0)
hollow box/plate:xwidth x yheight x zdepth and thickness>0
cylinder:        radius x yheight (thickness=0)
hollow cylinder: radius x yheight and thickness>0
sphere:          radius (yheight=0 thickness=0)
hollow sphere:   radius and thickness>0 (yheight=0)
any shape:       geometry=OFF file

The complex geometry option handles any closed non-convex polyhedra.
It computes the intersection points of the neutron ray with the object
transparently, so that it can be used like a regular sample object.
It supports the OFF and NOFF file format but not COFF (colored faces).
Such files may be generated from XYZ data using qhull/powercrust, and
viewed with geomview
The default size of the object depends of the OFF file data, but its
bounding box may be resized using xwidth,yheight and zdepth.

Example: Shape(radius=0.05, yheight=0.1)
Shape(geometry="socket.off")

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
geometry	str	Name of an Object File Format (OFF) file for complex geometry. The OFF file may be generated from XYZ coordinates using qhull/powercrust	0
radius	m	Outer radius of sample in (x,z) plane	0
xwidth	m	Horiz. dimension of sample (bounding box if off file), as a width	0
yheight	m	Vert. dimension of sample (bounding box if off file), as a height. A sphere shape is used when 0 and radius is set	0
zdepth	m	Depth of sample (bounding box if off file)	0
thickness	m	Thickness of hollow sample	0
nx			0
ny			1
nz			0
center	1	Flag to determine if OFF object is centered on its centre of mass.	1

AT (	,	,		) RELATIVE		Generate
ROTATED (	,	,		) RELATIVE

Links

• Source code for Shape.comp.
• Geomview and Object File Format (OFF)
• Powercrust/qhull

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[ Identification | Description | Input parameters | Links ]

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Last Modified: Monday, 07-Apr-2025 07:02:08 CEST