From b2dcb8a42e419e60ce689462c4a10a9004bd48b0 Mon Sep 17 00:00:00 2001
From: maj00r <maj00r@host>
Date: Sat, 31 Oct 2026 18:21:28 +0100
Subject: [PATCH] fix(vehicle): wheel clatter on an uneven track doesn't loop
 into a buzz

The phase of the rails was wrapped to the rail length of the track the
vehicle is on, while an axle can be on a track with longer rails. From
then on every frame looked like a joint crossed.
---
 vehicle/DynObj.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/vehicle/DynObj.cpp b/vehicle/DynObj.cpp
index 83354288..2c56cb7c 100644
--- a/vehicle/DynObj.cpp
+++ b/vehicle/DynObj.cpp
@@ -3665,16 +3665,19 @@ bool TDynamicObject::Update(double dt, double dt1)
                         auto const railphase { Axle0.RailPhase( axle.offset - 0.5 * fAxleDist ) };
                         auto crossed { false };
                         if( railphase >= 0.0 ) {
-                            crossed = axle.atjoints && std::abs( railphase - axle.distance ) > 0.5 * dRailLength;
+                            // the rails under the axle, which aren't always those under the track the vehicle is on
+                            crossed = axle.atjoints && std::abs( railphase - axle.distance ) > 0.5 * Axle0.GetTrack()->fSoundDistance;
                             axle.distance = railphase;
                         }
                         else {
                             axle.distance += dDOMoveLen * directioninconsist;
                             crossed = axle.distance < 0 || axle.distance > dRailLength;
+                            if( crossed ) {
+                                axle.distance = clamp_circular( axle.distance, dRailLength );
+                            }
                         }
                         axle.atjoints = ( railphase >= 0.0 );
                         if( crossed ) {
-                            axle.distance = clamp_circular( axle.distance, dRailLength );
                             if( MoverParameters->Vel > 0.1 ) {
                                 // NOTE: for combined clatter sound we supply 1/100th of actual value, as the sound module converts does the opposite, converting received (typically) 0-1 values to 0-100 range
                                 auto const frequency = true == axle.clatter.is_combined() ? MoverParameters->Vel * 0.01 : 1.0;