void RecalcUpExtent(ref AABB bb, int steps, int dx, int dz)
{
AABB upExtent = bb.Adjust(dx * steps, 32, dz * steps);
upsCount = AABB.FindIntersectingSolids(upExtent, level, ref ups);
}
void RecalcDownExtent(ref AABB bb, int steps, int dx, int dz)
{
AABB downExtent = bb.Adjust(dx * steps, -32, dz * steps);
downsCount = AABB.FindIntersectingSolids(downExtent, level, ref downs);
}