implemented bsp metrics

internal/bsp/metrics.go

@@ -0,0 +1,31 @@
+package bsp
+
+type Stats struct {
+	Nodes     int
+	Leaves    int
+	MaxDepth  int
+	TotalSegs int // Summe Segmente in Leaves (nach Splits)
+}
+
+func Measure(n *Node) Stats {
+	var st Stats
+	var rec func(*Node, int)
+	rec = func(x *Node, d int) {
+		if x == nil {
+			return
+		}
+		if d > st.MaxDepth {
+			st.MaxDepth = d
+		}
+		if x.Leaf != nil {
+			st.Leaves++
+			st.TotalSegs += len(x.Leaf.Segs)
+			return
+		}
+		st.Nodes++
+		rec(x.Left, d+1)
+		rec(x.Right, d+1)
+	}
+	rec(n, 0)
+	return st
+}