CREXSU ( profil, direct, smplfy, extsur, ifail )
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Create an extruded surface
Receives:
KI_tag_curve *profil --- curve to be extruded
KI_vec_direction direct --- extrusion direction vector
KI_cod_logical *smplfy --- simplification flag
Returns:
KI_tag_surface *extsur --- resulting extruded surface
KI_cod_error *ifail --- error code
Specific errors:
KI_impossible_sweep Cannot determine extruded geometry
KI_unsuitable_entity Not one of the allowed curve types
KI_invalid_geometry Invalid curve
Description:
This function creates an extruded or swept surface.
The curve 'profil' is extruded along the direction vector 'direct', the
new surface being the envelope of the curve.
If 'smplfy' is KI_false then the function will always return a surface
of type TYSUSE. If 'smplfy' is KI_true then, if possible, the function
will return an analytic surface which is equivalent to the extruded
surface. For example, an extruded line is almost always equivalent to
a plane.
The curve must be of one of the following types:
line
circle
ellipse
B-curve
A self intersecting surface may be returned, but it is not possible to
sweep a line along its own direction vector.
If 'profil' is not an orphan, the resulting surface will be created as
construction geometry in the owning part. A curve which is a dependent of
another entity may be extruded - for example, a single curve may be the
underlying curve of two swept surfaces.
