[Freeciv-Dev] (PR#9488) avoid a hex-related assertion in get_grid_color

["Jason Short" <jdorje@xxxxxxxxxxxxxxxxxxxxx>]

<URL: http://rt.freeciv.org/Ticket/Display.html?id=9488 >

If you use a "bad" tileset with a hex map, an assertion in 
get_grid_color will trigger because tiles that are adjacent on the 
tileset aren't actually adjacent on the map.

This is easily fixed.

(Perhaps we'd want to proceed with the standard choosing of the grid 
color as if the tiles were adjacent?  But instead I chose to treat the 
direction as invalid and to draw a default line there.)

jason

Index: client/mapview_common.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/client/mapview_common.c,v
retrieving revision 1.135
diff -u -r1.135 mapview_common.c
--- client/mapview_common.c     25 Jun 2004 16:38:48 -0000      1.135
+++ client/mapview_common.c     23 Jul 2004 15:24:47 -0000
@@ -94,10 +94,11 @@
 
   assert(is_real_map_pos(x1, y1));
 
-  if (is_real_map_pos(x2, y2)) {
-    normalize_map_pos(&x2, &y2);
-    assert(is_tiles_adjacent(x1, y1, x2, y2));
-
+  /* If the second position isn't real or is not adjacent to the first
+   * position (this is possible with hex topologies) use a fallback
+   * value. */
+  if (normalize_map_pos(&x2, &y2)
+      && is_tiles_adjacent(x1, y1, x2, y2)) {
     if (map_get_tile(x2, y2)->known == TILE_UNKNOWN) {
       return COLOR_STD_BLACK;
     }