Weapon enchantment

Does enchanting a weapon further make the extra damage exponential, or is it a straight line? It seems that enchanting Cloaks of Fire Resist makes them significantly stronger with each +1, has there been any quantification of the extra damage from weapon enchants?

also i got sal thuul for the first time and went into a shop, when i went to pick something up it asked if i wanted to commit this thievery, i chose no. If I chose yes does the shop keeper automatically detect it, or is there a chance for me to get away with it?

It's +1 damage per plus I'm pretty sure.

I don't have IVAN to test but doesn't it tell you what the bonus is from enchanting weapons? Try "E" to view your equipment, I'm pretty sure it will tell you. You have a MIN and MAX damage on each weapon. I don't think it's +1 each time, I think it alternates between +1 to MAX and +1 to MIN.

And yes the shop keeper will detect it. The entire city of Attnam will be after you.

I searched in the source code, here the formula :

Min Damage = Base Damage x 0.75
Max Damage = (Base Damage x 1.25) + 1
Base Damage = X + Enchantment

I don't give how you find X, because it need some of other var (Material, etc...).
A Leather Whip seem to have something like X = 1,5 for exemple.

+1  :  1-4                             +11 :  9-16 
+2  :  2-5                             +12 : 10-17
+3  :  3-6                             +13 : 10-19
+4  :  4-7                             +14 : 11-20
+5  :  4-9                             +15 : 12-21
+6  :  5-10                            +16 : 13-22
+7  :  6-11                            +17 : 13-24
+8  :  7-12                            +18 : 14-25
+9  :  7-14                            +19 : 15-26
+10 :  8-15                            +20 : 16-27

Cool, thanks Plan plan!