ok that should work, because thats how i do it with the other entities.
but this time, i want to stay the entity all the time at the same position on the screen.

in fact i want the following...after the player has bought a cup of coffee a 3d object that looks like a cup of coffee appears in the inventory. if the player now moves the cursor over the coffee cup it should rotate. if he releases it, the cup stops rotating and just stands still in the inventory. if the player clicks on the cup, it should become larger and be sticky at the cursour coordinates.

i will try it out with ent_create

edit:
i can't manage to convert the 3d coordinates to 2d coordinates.
vec_set(slot1,vector(20,9.74,-7.4));
vec_to_screen(slot1,top_view);
ent_create("kaffeebecher.mdl",slot1,item_kaffee);

i thought that would work but it doesnt. i dont want the cup to be created somewhere in the 3d world, but on the 2d screen.