a few geomview bugs?

[fjw]

When using the 4D rotation, selecting Exit on the 4D control panel
	sometimes exits the entire program; unfortunately, I haven't 
	been able to reliably reproduce this failure.

When using multiple cameras, trying to quit one camera using the 
	menu on the camera window ("quit camera") exits the entire program.

This may or may not be a bug.  When using a 4VECT file, I've seen 
	the bounding box seemingly not enclose the data points.
	see the file ~fjw/geomview/bbox.vect for an example.

When using the xgl version, it doesn't seem to display
	polylines consisting of a single vertex.  Run x
	on ~fjw/geomview/xglbug.vect to see this.



Geomview is a very impressive program and I'm looking forward to 
understanding more about it.

Rick