From 53f88d337dc4ac4e091d5c3c103587ee3cc444f3 Mon Sep 17 00:00:00 2001
From: Gael-de-Sailly <gael-de-sailly@netc.eu>
Date: Wed, 25 Nov 2020 13:12:24 +0100
Subject: [PATCH] Protect map preview from exceptions Since map preview is
 optional, an exception should not propagate to terrain calculation, so print
 an error message + traceback but keep the script running.

---
 terrainlib/view.py | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/terrainlib/view.py b/terrainlib/view.py
index 87843ab..d3d9c78 100644
--- a/terrainlib/view.py
+++ b/terrainlib/view.py
@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 
 import numpy as np
+import sys, traceback
 
 has_matplotlib = True
 try:
@@ -19,8 +20,6 @@ except ImportError: # No module matplotlib
 
 if has_matplotlib:
     def view_map(dem, lakes, scale=1, title=None):
-        if not has_matplotlib:
-            return
         lakes_sea = np.maximum(lakes, 0)
         water = np.maximum(lakes_sea - dem, 0)
         max_elev = lakes_sea.max()
@@ -48,15 +47,21 @@ if has_matplotlib:
             plt.title(title, fontweight='bold')
 
     def update(*args, t=0.01, **kwargs):
-        plt.clf()
-        view_map(*args, **kwargs)
-        plt.pause(t)
+        try:
+            plt.clf()
+            view_map(*args, **kwargs)
+            plt.pause(t)
+        except:
+            traceback.print_exception(*sys.exc_info())
 
     def plot(*args, **kwargs):
-        plt.clf()
-        view_map(*args, **kwargs)
-        plt.pause(0.01)
-        plt.show()
+        try:
+            plt.clf()
+            view_map(*args, **kwargs)
+            plt.pause(0.01)
+            plt.show()
+        except Exception as e:
+            traceback.print_exception(*sys.exc_info())
 
 else:
     def update(*args, **kwargs):