+ *
+ * TODO:
+ *
+ * - Figure out what to do if a puzzle requests a size bigger than
+ * the screen will take. In principle we could put scrollbars in
+ * the window, although that would be pretty horrid. Another
+ * option is to detect in advance that this will be a problem -
+ * we can probably tell this using midend_size() before actually
+ * generating the puzzle - and simply refuse to do it.