Fix #7371: Avoid dependency on foundations of town tile during saveload

OpenTTD · Apr 1, 2019 · 97e92ff · 97e92ff
1 parent 92d5835
commit 97e92ff
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/src/viewport.cpp b/src/viewport.cpp
@@ -2119,7 +2119,9 @@ ViewportSignKdtreeItem ViewportSignKdtreeItem::MakeTown(TownID id)
 	item.id.town = id;
 
 	const Town *town = Town::Get(id);
-	Point pt = RemapCoords2(TileX(town->xy) * TILE_SIZE, TileY(town->xy) * TILE_SIZE);
+	/* Avoid using RemapCoords2, it has dependency on the foundations status of the tile, and that can be unavailable during saveload, leading to crashes.
+	 * Instead "fake" foundations by taking the highest Z coordinate of any corner of the tile. */
+	Point pt = RemapCoords(TileX(town->xy) * TILE_SIZE, TileY(town->xy) * TILE_SIZE, GetTileMaxZ(town->xy) * TILE_HEIGHT);
 
 	pt.y -= 24 * ZOOM_LVL_BASE;