[pschlik]

While trying to set up a recording of an activity, I wanted to use the replay feature to have a slightly better recording environment. Unfortunately, I found a reproducible crash when replaying my save. It turns out that when the replay attempts to play back closing or opening an anglecock, the game outright crashes. Check out this crash dump:

Error: System.NullReferenceException: Object reference not set to an instance of an object.
   at Orts.Common.ToggleAngleCockBCommand.Redo() in C:\Jenkins\jobs\Open Rails Stable\workspace\Source\Orts.Simulation\Common\Commands.cs:line 929
   at Orts.Common.CommandLog.ReplayCommand(Double elapsedTime, List`1 replayCommandList, ICommand c) in C:\Jenkins\jobs\Open Rails Stable\workspace\Source\Orts.Simulation\Common\CommandLog.cs:line 121
   at Orts.Common.CommandLog.Update(List`1 replayCommandList) in C:\Jenkins\jobs\Open Rails Stable\workspace\Source\Orts.Simulation\Common\CommandLog.cs:line 107
   at Orts.Viewer3D.Viewer.Update(RenderFrame frame, Single elapsedRealTime) in C:\Jenkins\jobs\Open Rails Stable\workspace\Source\RunActivity\Viewer3D\Viewer.cs:line 775
   at Orts.Viewer3D.Processes.UpdaterProcess.Update() in C:\Jenkins\jobs\Open Rails Stable\workspace\Source\RunActivity\Viewer3D\Processes\UpdaterProcess.cs:line 128
   at Orts.Viewer3D.Processes.UpdaterProcess.DoUpdate() in C:\Jenkins\jobs\Open Rails Stable\workspace\Source\RunActivity\Viewer3D\Processes\UpdaterProcess.cs:line 108
   at Orts.Viewer3D.Processes.UpdaterProcess.UpdaterThread() in C:\Jenkins\jobs\Open Rails Stable\workspace\Source\RunActivity\Viewer3D\Processes\UpdaterProcess.cs:line 74
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

The log file does seem to know that I used the anglecock and uncoupled, so this seems to be an issue purely with playback.

Command: 09:00:25.39 Orts.Common.ToggleAngleCockBCommand - close
Command: 09:00:27.58 Orts.Viewer3D.UncoupleCommand - 0
Command: 09:00:30.55 Orts.Viewer3D.UseCabCameraCommand

To reproduce, simply start any activity, use the F9 menu to open or close an anglecock, save the game, quit to main menu, then Resume/Replay and replay the save from the start. Should be an instant 100% reproducible crash when the replay reaches the time you changed the anglecock. I did reproduce this on the official 1.5.1 release, the current testing version of 1.5.1, and new year rev 140.5.