From 2cbb42f9a9440a7c8f4ab1820d0837f227842586 Mon Sep 17 00:00:00 2001
From: Jonathan G Rennison <j.g.rennison@gmail.com>
Date: Sat, 27 Feb 2021 19:24:22 +0000
Subject: [PATCH] Add fast path to catenary drawing in MaskWireBits

---
 src/elrail.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/elrail.cpp b/src/elrail.cpp
index 6d971ebfe1..bdcd4613f0 100644
--- a/src/elrail.cpp
+++ b/src/elrail.cpp
@@ -155,6 +155,8 @@ static DualTrackBits GetRailTrackBitsUniversal(TileIndex t, byte *override)
  */
 static TrackBits MaskWireBits(TileIndex t, TrackBits tracks)
 {
+	if (likely(HasAtMostOneBit(tracks))) return tracks;
+
 	if (!IsPlainRailTile(t)) return tracks;
 
 	TrackdirBits neighbour_tdb = TRACKDIR_BIT_NONE;