1 files changed, 51 insertions, 0 deletions
diff --git a/src/bridge_map.cpp b/src/bridge_map.cpp
new file mode 100644
index 000000000..8e2405ea3
--- /dev/null
+++ b/src/bridge_map.cpp
@@ -0,0 +1,51 @@
+/* $Id$ */
+
+#include "stdafx.h"
+#include "openttd.h"
+#include "bridge_map.h"
+#include "variables.h"
+
+
+TileIndex GetBridgeEnd(TileIndex tile, DiagDirection dir)
+{
+	TileIndexDiff delta = TileOffsByDiagDir(dir);
+
+	dir = ReverseDiagDir(dir);
+	do {
+		tile += delta;
+	} while (!IsBridgeTile(tile) || GetBridgeRampDirection(tile) != dir);
+
+	return tile;
+}
+
+
+TileIndex GetNorthernBridgeEnd(TileIndex t)
+{
+	return GetBridgeEnd(t, ReverseDiagDir(AxisToDiagDir(GetBridgeAxis(t))));
+}
+
+
+TileIndex GetSouthernBridgeEnd(TileIndex t)
+{
+	return GetBridgeEnd(t, AxisToDiagDir(GetBridgeAxis(t)));
+}
+
+
+TileIndex GetOtherBridgeEnd(TileIndex tile)
+{
+	assert(IsBridgeTile(tile));
+	return GetBridgeEnd(tile, GetBridgeRampDirection(tile));
+}
+
+uint GetBridgeHeight(TileIndex t)
+{
+	uint h;
+	uint tileh = GetTileSlope(t, &h);
+	uint f = GetBridgeFoundation(tileh, DiagDirToAxis(GetBridgeRampDirection(t)));
+
+	// one height level extra if the ramp is on a flat foundation
+	return
+		h + TILE_HEIGHT +
+		(IS_INT_INSIDE(f, 1, 15) ? TILE_HEIGHT : 0) +
+		(IsSteepSlope(tileh) ? TILE_HEIGHT : 0);
+}