FlatCollision

port to 26.1.x

replaced autoboxing HashMap with Int2IntOpenHashMap in slot map, use mutable BlockPos for particle collision. just some improvements along with a version for 1.21.1

replaced autoboxing HashMap with Int2IntOpenHashMap in slot map, use mutable BlockPos for particle collision. just some improvements along with a version for 1.21.1

First Release Of FlatCollision