1 files changed, 37 insertions, 0 deletions
diff --git a/src/yapf/yapf_costbase.hpp b/src/yapf/yapf_costbase.hpp
new file mode 100644
index 000000000..df4d9e787
--- /dev/null
+++ b/src/yapf/yapf_costbase.hpp
@@ -0,0 +1,37 @@
+/* $Id$ */
+
+#ifndef  YAPF_COSTBASE_HPP
+#define  YAPF_COSTBASE_HPP
+
+struct CYapfCostBase {
+	static const TrackdirBits   c_upwards_slopes[16];
+
+	FORCEINLINE static bool stSlopeCost(TileIndex tile, Trackdir td)
+	{
+		if (IsDiagonalTrackdir(td)) {
+			if (IsBridgeTile(tile)) {
+				// it is bridge ramp, check if we are entering the bridge
+				if (GetBridgeRampDirection(tile) != TrackdirToExitdir(td)) return false; // no, we are living it, no penalty
+				// we are entering the bridge
+				// if the tile slope is downwards, then bridge ramp has not upward slope
+				uint tile_slope = GetTileSlope(tile, NULL) & 0x0F;
+				if ((c_upwards_slopes[tile_slope] & TrackdirToTrackdirBits(ReverseTrackdir(td))) != 0) return false; // tile under ramp goes down, no penalty
+				// tile under ramp isn't going down, so ramp must go up
+				return true;
+			} else {
+				// not bridge ramp
+				if (IsTunnelTile(tile)) return false; // tunnel entry/exit doesn't slope
+				uint tile_slope = GetTileSlope(tile, NULL) & 0x0F;
+				if ((c_upwards_slopes[tile_slope] & TrackdirToTrackdirBits(td)) != 0) return true; // slopes uphill => apply penalty
+			}
+		}
+		return false;
+	}
+};
+
+struct CostRailSettings {
+	// look-ahead signal penalty
+};
+
+
+#endif /* YAPF_COSTBASE_HPP */