Different Object Category

Currently there are 4 categories, with the first category having a 45%
spawn chance (Small walls, ramps, random small items and roadblocks) the
second and third both have 25% (Some bunkers, larger walls. A Long Tall
wall has a larger spawn chance in here then in the first category,
because there are way less items) and the last category has 5% (Bunkers
with a floor)