LAYERINSTANCE:set_bounds( x, y, width, height )
Set the value of grd_x, grd_y, grd_width and grd_height for this layer instance to the provided value.
Parameters:
x An integer value to set to grd_x of this layer instance
y An integer value to set to grd_y of this layer instance
width An integer value to set to grd_width of this layer instance's layer
height An integer value to set to grd_height of this layer instance's layer