From 6e97511bcb11a83931e7ff26f3834f1d69ad1704 Mon Sep 17 00:00:00 2001
From: yexo <yexo@openttd.org>
Date: Sun, 3 Jan 2010 12:42:50 +0000
Subject: [PATCH] (svn r18696) -Fix [FS#3404]: AITile::IsCoastTile returned
 false for coast tiles with trees on them.

---
 src/ai/api/ai_tile.cpp | 4 +++-
 src/ai/api/ai_tile.hpp | 3 ++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/ai/api/ai_tile.cpp b/src/ai/api/ai_tile.cpp
index b7e41d7faa..a1c2f1c5ef 100644
--- a/src/ai/api/ai_tile.cpp
+++ b/src/ai/api/ai_tile.cpp
@@ -17,6 +17,7 @@
 #include "../../road_map.h"
 #include "../../water_map.h"
 #include "../../clear_map.h"
+#include "../../tree_map.h"
 #include "../../town.h"
 #include "../../landscape.h"
 
@@ -68,7 +69,8 @@
 {
 	if (!::IsValidTile(tile)) return false;
 
-	return ::IsTileType(tile, MP_WATER) && ::IsCoast(tile);
+	return (::IsTileType(tile, MP_WATER) && ::IsCoast(tile)) ||
+		(::IsTileType(tile, MP_TREES) && ::GetTreeGround(tile) == TREE_GROUND_SHORE);
 }
 
 /* static */ bool AITile::IsStationTile(TileIndex tile)
diff --git a/src/ai/api/ai_tile.hpp b/src/ai/api/ai_tile.hpp
index 8f5f4a1027..6b254899f0 100644
--- a/src/ai/api/ai_tile.hpp
+++ b/src/ai/api/ai_tile.hpp
@@ -140,7 +140,8 @@ public:
 	 * @param tile The tile to check.
 	 * @pre AIMap::IsValidTile(tile).
 	 * @return True if and only if the tile is a coast tile.
-	 * @note Building on coast tiles in general is more expensive.
+	 * @note Building on coast tiles in general is more expensive. This is not
+	 *  true if there are also trees on the tile, see #HasTreeOnTile.
 	 */
 	static bool IsCoastTile(TileIndex tile);