diff --git a/lib/xmet/hodograph.py b/lib/xmet/hodograph.py
index 9110ad3..15fee0e 100644
--- a/lib/xmet/hodograph.py
+++ b/lib/xmet/hodograph.py
@@ -308,8 +308,9 @@ class Hodograph():
 
             offset += interval
 
-    def draw(self, cr: cairo.Context, x, y, sounding: Sounding):
-        self.extents = self.find_extents(sounding)
+    def draw(self, cr: cairo.Context, x, y, sounding: Sounding, zoom: bool=True):
+        if zoom:
+            self.extents = self.find_extents(sounding)
 
         cr.rectangle(x, y, self.width, self.height)
         cr.clip()