diff --git a/src/yapf/yapf_common.hpp b/src/yapf/yapf_common.hpp
index 43fdb68869..a0725a1ff6 100644
--- a/src/yapf/yapf_common.hpp
+++ b/src/yapf/yapf_common.hpp
@@ -160,7 +160,7 @@ public:
 		int dy = abs(y1 - y2);
 		int dmin = min(dx, dy);
 		int dxy = abs(dx - dy);
-		int d = dmin * 7 + (dxy - 1) * (10 / 2);
+		int d = dmin * YAPF_TILE_CORNER_LENGTH + (dxy - 1) * (YAPF_TILE_LENGTH / 2);
 		n.m_estimate = n.m_cost + d;
 		assert(n.m_estimate >= n.m_parent->m_estimate);
 		return true;
diff --git a/src/yapf/yapf_ship.cpp b/src/yapf/yapf_ship.cpp
index 901545838a..36b0b00762 100644
--- a/src/yapf/yapf_ship.cpp
+++ b/src/yapf/yapf_ship.cpp
@@ -113,11 +113,11 @@ public:
 	FORCEINLINE bool PfCalcCost(Node& n, const TrackFollower *tf)
 	{
 		/* base tile cost depending on distance */
-		int c = IsDiagonalTrackdir(n.GetTrackdir()) ? 10 : 7;
+		int c = IsDiagonalTrackdir(n.GetTrackdir()) ? YAPF_TILE_LENGTH : YAPF_TILE_CORNER_LENGTH;
 		/* additional penalty for curves */
 		if (n.m_parent != NULL && n.GetTrackdir() != NextTrackdir(n.m_parent->GetTrackdir())) {
 			/* new trackdir does not match the next one when going straight */
-			c += 10;
+			c += YAPF_TILE_LENGTH;
 		}
 
 		c += YAPF_TILE_LENGTH * tf->m_tiles_skipped;