--- glines/src/glines.c~	2013-03-27 07:19:56.000000000 +0400
+++ glines/src/glines.c	2013-04-03 00:23:45.773674440 +0400
@@ -439,6 +439,8 @@
 {
   guint i;
   cairo_pattern_t *pattern;
+  if (preview[0] == 0)
+    init_preview();
 
   for (i = 0; i < MAXNPIECES; i++) {