GML Level generation based on specific coordinates/spot (solved ? )

[Schtipadoo]

was looking on the code and, i dont know how to approach this, i want to make so my ds_grid will generate the level within a spot i want instead of the whole room, or being fixed to the x and y of the room...

but i only got height and width

code to make the magic happen is based on this video

 

[Schtipadoo]

(current solution)

i put a spot, (stretched object)
and made the generator make pre object, basically just an object that will make another,
if this pre object is not in the area it vanishes,
so it works fine!