07.05.2016, 11:00
Directly under a player? I believe sa-mp's skin heights are all(or almost all) the same being 1.8 or 2.0, so you could get the player'pos and just create an object 0.9-1.0 below the z you get, and it will be directly under him, however if you want to create the object on the land/object under him, you need to either use MapAndreas or ColAndreas(recommended).