CRPRSO ( centre, axis, radius, nsides, height, prism, ifail )
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Create prismatic solid
Receives:
KI_vec_position centre --- centre of prism
KI_vec_axis axis --- axis of prism
KI_dbl_radius *radius --- radius of enclosing cylinder
int *nsides --- number of sides
<KI_dbl_distance> *height --- height of prism
Returns:
KI_tag_body *prism --- prism
KI_cod_error *ifail --- failure indicator
Specific errors:
KI_lt_3_sides Number of sides is less than 3
Description:
If 'height' is positive, a body is created that is a right regular prism of
'nsides' sides. One of the end faces (regular polygons of 'nsides' sides) is
centred at 'centre', and the prism extends a distance 'height' in the
direction of 'axis'. The prism is inscribed in a cylinder of radius 'radius'.
If 'height' is zero, a sheet body is created whose face is a regular polygon
of 'nsides' sides. The polygon is centred at 'centre', and the normal to the
its plane face is parallel to 'axis'. Its circumscribing circle has radius
'radius'.
In either case, if 'axis' is parallel to the Z-axis (0,0,1) then one side
(face or edge) will be perpendicular to the Y-axis, on the positive-Y side of
'centre'. If 'axis' is not parallel to the Z-axis, the orientation of the body
about 'axis' is undefined.
