diff -r cd88f4b7cba0 -r c5c09cfde63a src/ai/api/ai_tilelist_valuator.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/ai/api/ai_tilelist_valuator.cpp	Sat Apr 14 20:01:25 2007 +0000
@@ -0,0 +1,14 @@
+#include "ai_tilelist_valuator.hpp"
+#include "../../tile.h"
+
+int32 AITileListBuildable::Valuate(int32 tile) const
+{
+	switch (::GetTileType(tile)) {
+		default: return 1;
+		case MP_VOID:
+		case MP_HOUSE:
+		case MP_STATION:
+		case MP_INDUSTRY:
+		case MP_UNMOVABLE: return 0;
+	}
+}