fix adding characters at the end of the window

When the number of columns wasn't exactly 2 (the default), adding a
character at the end of the window could fail at scrolling thus yielding
corrupted output.

1 files changed, 1 insertions, 1 deletions

diff --git a/tcvt.py b/tcvt.py
index 3831a83..1b3bbfd 100755
--- a/tcvt.py
+++ b/tcvt.py
@@ -168,7 +168,7 @@ class Columns:
     def addch(self, char):
         if self.xpos == self.columnwidth - 1:
             self.curwin.insch(self.curypos, self.curxpos, char, self.attrs)
-            if self.ypos + 1 == 2 * self.height:
+            if self.ypos + 1 == self.numcolumns * self.height:
                 self.scroll()
                 self.move(self.ypos, 0)
             else: