//see in what child batch it should go
public void Choose(_collider col)
{
for(int i = 0; i < 2; i++)
for(int j = 0; j < 2; j++)
{
if (col.Minmax().Intersects(childs[i, j].cbound.Minmax()))
childs[i, j].Add(col);
}
}
public void Add(_collider col)
{
if (col == null) return;
cols.Add(col);
AABB added = col.Minmax();
AABB old = new AABB(minmax);
//find outerbound to cut
float minx = Math.Min(added.x, old.x);
float miny = Math.Min(added.y, old.y);
float maxx = Math.Max(added.x + added.w, old.x + old.w);
float maxy = Math.Max(added.y + added.h, old.y + old.h);
minmax.x = minx;
minmax.y = miny;
minmax.w = maxx - minx;
minmax.h = maxy - miny;
root.MakeBound(minmax);
counter++;
}