From: Olaf Lenz (olenz_at_Physik.Uni-Bielefeld.DE)
Date: Thu Jul 22 2004 - 11:08:38 CDT

Hello again!

As a significant amount of the traffic on this list is currently caused by me, I
hope that I don't get on people's nerves....

I have a few suggestions for extensions of the selection language that would
probably be useful:

1. New constants "A", "B", "C", "alpha", "beta", "gamma" of floating value that
return the unit cell parameters (corresponding to the molinfo get/set keywords).

These could be applied when handling the periodicity of the box. For example,
one could use

        x> 0.0 and y > 0.0 and z > 0.0 and x < A and y < B and z < C

to select all the particles that are actually in the central box.

2. New keyword "picked" that selects the last picked atom (and none if none was
picked so far). Very nice for reps that interactively "highlight"
atoms/residues/etc. (Yes, I know, I've already asked for that one, but I didn't
get any answer). For example, you could have one "bonds" rep that selects all
atoms, and one "VDW" rep that selects "samed resid as picked".
This could be nice in a talk when you pick the residues you're talking about.

Olaf