Hi Tig
Thanks for reply. Yes that looks promising, however I'm not remotely a programmer, so do you think someone may consider this an interesting/useful plugin - I'm sure many of the landscape folk would find this useful in a number of ways.
Also would it be possible for such a plugin to make each face a component and then each face-component could hold attributes (I think this is what you were alluding to in your post on colour by slope in viewtopic.php?f=323&t=20635) such as solar gain incidence, surface erodibility, soil type etc.
Sorry if this is a bit vague, but people are doing interesting things with SU and I don't know what's possible.
cheers