Trigger Question (involving terrain)

Alright, this question here comes back from along time ago when i played StarCraft and i had the same problem. I now know its impossible in SC, but im wondering if its possible here.

Im wondering if there is any way (JASS, triggers, or something else) that you can actually modify terrain (i.e. change the height, texture, ect). I've never seen it done, so i expect the answer to be no, but i thought i'd ask anyway.

thanks for the help.

Height can be changed via "Terrain Defformations" (its a GUI action) but changing via deformations does NOT change pathing, so to change pathing after such a thing you would have to use pathing modifiers.