(svn r8014) -Codechange (r7573): When a tile is cleared, empty the general purpose bits in

extra as well, unless they are (or could be) used for bridges. This means these
bits don't have to be cleared seperately when non-bridgeable tiles are removed.

3 files changed, 6 insertions, 5 deletions

diff --git a/src/clear_map.h b/src/clear_map.h
index 50ae63b1b..85c52a1a7 100644
--- a/src/clear_map.h
+++ b/src/clear_map.h
@@ -5,6 +5,7 @@
 
 #include "macros.h"
 #include "tile.h"
+#include "bridge_map.h"
 
 /* ground type, m5 bits 2...4
  * valid densities (bits 0...1) in comments after the enum
@@ -123,12 +124,17 @@ static inline void SetFenceSW(TileIndex t, uint h)
 
 static inline void MakeClear(TileIndex t, ClearGround g, uint density)
 {
+	/* If this is a non-bridgeable tile, clear the bridge bits while the rest
+	 * of the tile information is still here. */
+	if (!MayHaveBridgeAbove(t)) SB(_m[t].extra, 6, 2, 0);
+
 	SetTileType(t, MP_CLEAR);
 	SetTileOwner(t, OWNER_NONE);
 	_m[t].m2 = 0;
 	_m[t].m3 = 0;
 	_m[t].m4 = 0 << 5 | 0 << 2;
 	SetClearGroundDensity(t, g, density);
+	SB(_m[t].extra, 2, 4, 0);
 }
 
 
diff --git a/src/terraform_gui.c b/src/terraform_gui.c
index f0a48b2e2..8d6e1276a 100644
--- a/src/terraform_gui.c
+++ b/src/terraform_gui.c
@@ -76,12 +76,8 @@ static void GenerateRockyArea(TileIndex end, TileIndex start)
 	BEGIN_TILE_LOOP(tile, size_x, size_y, TileXY(sx, sy)) {
 		switch (GetTileType(tile)) {
 			case MP_CLEAR:
-				MakeClear(tile, CLEAR_ROCKS, 3);
-				break;
-
 			case MP_TREES:
 				MakeClear(tile, CLEAR_ROCKS, 3);
-				ClearBridgeMiddle(tile);
 				break;
 
 			default: continue;
diff --git a/src/tree_cmd.c b/src/tree_cmd.c
index ccdbcfbad..47b9a4a37 100644
--- a/src/tree_cmd.c
+++ b/src/tree_cmd.c
@@ -587,7 +587,6 @@ static void TileLoop_Trees(TileIndex tile)
 					case TREE_GROUND_ROUGH: MakeClear(tile, CLEAR_ROUGH, 3); break;
 					default: MakeClear(tile, CLEAR_SNOW, GetTreeDensity(tile)); break;
 				}
-				ClearBridgeMiddle(tile);
 			}
 			break;