[ REQ 5019]: evolver problems

["John Sullivan" <sullivan>]

Ken,

I've mentioned before the problem that sometimes when evolver talks to
geomview, geomview will stop deleting old frames, and you get a mess on
the screen.  You encountered this problem in your demo on Monday.  It may
technically be a geomview bug, but it occurs exactly when you switch to
a new file _not_ in the current directory.  You must pass the full name
with the "/"s to geomview, and this somehow confuses it.  Until this is
fixed in geomview, the right work-around is to only use the tail of the
file name (after the last "/") as the name passed to geomview.

The evolver bug that _I_ ran into in my demo was that if view_4d is on,
and then you read in a new file (even one with space_dim=3), the view_4d
does not get reset to OFF.

When preparing my demos, I noticed what I think is a problem with the
way transformation matrices are passed to geomview if space_dim=4.
I specified two matrices
-1 0 0 0 0   0 1 0 0 0    0 0 1 0 0  0 0 0 1 0   0 0 0 0 1
and
1 0 0 0 0   0 1 0 0 0    0 0 -1 0 0   0 0 0 1 0  0 0 0 0 1

but what geomview was sent was
-1 0 0 0   0 1 0 0   0 0 1 0   0 0 0 1
and
1 0 0 0  0 1 0 0  0 0 1 0    0 0 0 -1
which negates the w, not the z coordinate.  I could find any 5x5 to
put into the evolver which would end up sending geomview
1 0 0 0   0 1 0 0  0 0 -1 0   0 0 0 1
which is what I wanted.

-John