Re: Source code for "nose" module

[slevy]

> 1) Is there a data conversion utility that will convert Bezier (or
> B-Spline) surface representations to OOGL or OFF format so that geomview
> will understand it ?

Note that Geomview already accepts Bezier patches directly (though not
B-splines); will that do?  See the manual section on file formats, or
GEOMROOT/man/cat5/oogl.5.  As for converting from other formats of
Bezier patches into Geomview format, we don't have any such tools,
but the format isn't complicated.

> 2) Can you send me the source code for the "nose" module, so that i can
> understand how the picking has been implemented ?

You can get source for "nose" and lots of other things by picking up
pub/software/geomview/geomview-src.tar.Z by anonymous FTP from geom.umn.edu.

The details of picking are built into geomview; you can test them for yourself
by loading some patch-based object (e.g. "teapot.bez"), entering the
command into geomview's Commands panel:

   (interest (pick world))

and then clicking the right mouse button over an object.  A message
will be written to the terminal from which you started geomview.
It includes among other things (see the documentation for the "pick" command):
   - the 3-D point clicked on,
   - the "path" to the picked object (one of whose components will be a
	sequence number of the picked patch in its list of Bezier patches), and
   - the index of the picked face in the polygonalized version of picked patch.
	Bezier patches are automatically diced into a quadrilateral mesh,
	with by default a 10x10 grid of vertices i.e. a 9x9 grid of faces,
	so its 81 faces are numbered from 0 through 80.

This might give some idea of the effort you'd have to go through to use
geomview this way.  It might well be practical.