diff --git a/Terrain2/GameViewController.swift b/Terrain2/GameViewController.swift
index 61d5b2b..6e7e20f 100644
--- a/Terrain2/GameViewController.swift
+++ b/Terrain2/GameViewController.swift
@@ -72,7 +72,6 @@ class GameViewController: NSViewController {
             if let progress = renderer.scheduleAlgorithmIteration() {
                 progressIndicator.isHidden = false
                 progressObservation = progress.observe(\.fractionCompleted) { [weak self] (progress: Progress, change: NSKeyValueObservedChange<Double>) in
-                    print("Observing progress change: \(progress.fractionCompleted)")
                     DispatchQueue.main.async {
                         guard let strongSelf = self else {
                             return
diff --git a/Terrain2/Renderer.swift b/Terrain2/Renderer.swift
index 9bae19d..b1ff7f0 100644
--- a/Terrain2/Renderer.swift
+++ b/Terrain2/Renderer.swift
@@ -48,7 +48,11 @@ class Renderer: NSObject, MTKViewDelegate {
 
     var terrain: Terrain
 
-    var drawLines = true
+    var drawLines = true {
+        didSet {
+            print("Line drawing \(drawLines ? "enabled" : "disabled")")
+        }
+    }
 
     private var iterateTerrainAlgorithm = true
     private var didUpdateTerrain = false