From c014e35aecd831001b1f1e1fec4a53b61db1d664 Mon Sep 17 00:00:00 2001
From: Stuart Buchanan <stuart_d_buchanan@yahoo.co.uk>
Date: Sun, 12 Jan 2014 19:52:30 +0000
Subject: [PATCH] Add ability to clear screen.window, and use it.

---
 Nasal/screen.nas            | 5 +++++
 Nasal/tutorial/tutorial.nas | 4 ++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/Nasal/screen.nas b/Nasal/screen.nas
index 496a45474..1fbdc3683 100644
--- a/Nasal/screen.nas
+++ b/Nasal/screen.nas
@@ -116,6 +116,11 @@ var window = {
 			settimer(func { me._write_(); } , 0, 1);
 		append(me.writebuffer, lines);
 	},
+	clear : func() {
+	  me.lines = [];
+	  me.writebuffer = [];
+	  me.show();
+	},
 	show : func {
 		if (me.dialog != nil)
 			me.close();
diff --git a/Nasal/tutorial/tutorial.nas b/Nasal/tutorial/tutorial.nas
index d6ab8b953..4c50659b8 100644
--- a/Nasal/tutorial/tutorial.nas
+++ b/Nasal/tutorial/tutorial.nas
@@ -105,6 +105,7 @@ var startTutorial = func {
 	# <init>
 	do_group(tutorialN.getNode("init"));
 	is_running(1);  # needs to be after "presets-commit"
+	display.clear();
 	display.show();
 
 	# Pick up any weather conditions/scenarios set
@@ -121,6 +122,7 @@ var stopTutorial = func {
 		set_properties(end);
 		run_nasal(end);
 		set_view(end) or view.point.restore();
+		say("Tutorial finished.");
 		settimer(func() { if (!is_running()) { display.close(); } }, 10);
 	}
 	set_marker();
@@ -150,8 +152,6 @@ var step_tutorial = func(id) {
 	# <end>
 	if (current_step >= size(steps)) {
 		var end = tutorialN.getNode("end");
-		say_message(end, "Tutorial finished.");
-		#say_message(nil, "Deviations: " ~ num_errors);
 		stopTutorial();
 		return;
 	}