Placing Objects on Terrain?

Hello reader,

i've been trying to make a roblox game where i am able to allow the players to place structures such as walls, or chests, etc.. but im having troubles finding a way to make it follow the laws of the Roblox terrain. My assumption would be to make the object follow the players cursor until they click to confirm the placement. Could i get some pointers in how i can go about doing this?

I'm pretty sure the game "booga booga" does pretty much what im thinking of but i cant seem to get the product im looking for.

thanks in advance, Insane