[postgis-users] OT: calculating slope in a TIN

[Tyler Mitchell]

In light of the recent discussion/announcement regarding creating tins from 
multipoint data, could anyone help me learn the math/process behind 
calculating an attribute like aspect (also slope) from such data.

Can anyone guide me to either:
1) web resources on similar geometry topics
2) books or journals that deal with these kinds of issues
3) a more appropriate mailing list to ask these questions

Tyler