--- a/cmd/octree2contour/main.go	Thu Sep 20 00:13:47 2018 +0200
+++ b/cmd/octree2contour/main.go	Thu Sep 20 11:32:03 2018 +0200
@@ -17,7 +17,7 @@
 
 type result struct {
 	h         float64
-	triangles int
+	numPoints int
 }
 
 func processLevels(
@@ -28,21 +28,23 @@
 ) {
 	defer wg.Done()
 	for h := range jobs {
-		var triangles int
-		tree.horizontal(h, func([]int32) {
-			triangles++
+		var points []vertex
+		tree.horizontal(h, func(t *triangle) {
+			points = t.intersectH(h, points)
 		})
-		results <- result{h, triangles}
+		results <- result{h, len(points)}
 	}
 }
 
 func process(tree *octree) {
-	var triangles int
+	var numPoints int
 	start := time.Now()
 	if *one {
-		tree.horizontal(*step, func([]int32) {
-			triangles++
+		var points []vertex
+		tree.horizontal(*step, func(t *triangle) {
+			points = t.intersectH(*step, points)
 		})
+		numPoints = len(points)
 	} else {
 
 		results := make(chan result)
@@ -78,14 +80,13 @@
 			return all[i].h < all[j].h
 		})
 
-		var sum int
 		for i := range all {
 			a := &all[i]
-			sum += a.triangles
-			log.Printf("level %f: %d\n", a.h, a.triangles)
+			numPoints += a.numPoints
+			log.Printf("level %f: %d\n", a.h, a.numPoints)
 		}
-		log.Printf("num triangles: %d\n", sum)
 	}
+	log.Printf("num points: %d\n", numPoints)
 	log.Printf("processing took: %s\n", time.Since(start))
 }