Automatic merge of T1.5.1-1004-g6fd841761e and 21 pull requests

- Pull request #799 at dfc715e: Consolidated wind simulation
- Pull request #839 at d00beb9: First phase of https://blueprints.launchpad.net/or/+spec/additional-cruise-control-parameters
- Pull request #876 at f92de76: docs: add source for documents previously on website to source Documentation folder
- Pull request #882 at 8f695a4: Blueprint/train car operations UI window
- Pull request #885 at 2728d6d: feat: Add notifications to Menu
- Pull request #891 at 9a1d6b2: Auto save
- Pull request #892 at 1f5ba4c: Signal Function OPP_SIG_ID_TRAINPATH
- Pull request #896 at 5866028: First implementation of https://blueprints.launchpad.net/or/+spec/specific-sounds-for-ai-trains
- Pull request #900 at c27f32d: DMI updates
- Pull request #903 at 3e390b8: Downloading route content (Github, zip)
- Pull request #912 at 359cfee: New Triple Valve Features Vol. 2
- Pull request #922 at 0d3e70b: Autopilot for timetable mode
- Pull request #946 at 91a03af: Advanced track sounds
- Pull request #949 at a4a44b5: Oil Burning Locomotive
- Pull request #952 at 8347095: Investigation - Pulsing graphics
- Pull request #953 at a519452: Fix Lights Crash on Corrupt Shapes
- Pull request #954 at 84c2f4b: Add Support for Multiple Track Profiles
- Pull request #956 at 406cba6: Map settings saved
- Pull request #959 at 2452cb0: Fix TrackViewer crash on big zoom value
- Pull request #960 at c8e2a28: Fix draw state name in scripts
- Pull request #962 at 46d0472: Fix pantographs on unpowered cars

Author: openrails-bot

Source/Orts.Simulation/Simulation/Signalling/Signals.cs

@@ -64,7 +64,7 @@ public class Signals
         public int noSignals;
         private int foundSignals;
 
-        private static int updatecount;
+        private static int UpdateIndex;
 
         public List<TrackCircuitSection> TrackCircuitList;
         private Dictionary<int, CrossOverItem> CrossoverList = new Dictionary<int, CrossOverItem>();
@@ -553,6 +553,11 @@ private void BuildSignalWorld(Simulator simulator, SignalConfigurationFile sigcf
 
         }  //BuildSignalWorld
 
+        Stopwatch UpdateTimer = new Stopwatch();
+        long UpdateCounter = 0;
+        long UpdateTickTarget = 10000;
+        // long DebugUpdateCounter = 0;
+
         /// <summary>
         /// Update : perform signal updates
         /// </summary>
@@ -562,30 +567,39 @@ public void Update(bool preUpdate)
 
             if (foundSignals > 0)
             {
-
                 // loop through all signals
                 // update required part
-                // in preupdate, process all
-
-                int totalSignal = foundSignals;
-
-                int updatestep = (totalSignal / 20) + 1;
-                if (preUpdate)
-                {
-                    updatestep = totalSignal;
-                }
-
-                for (int icount = updatecount; icount < Math.Min(totalSignal, updatecount + updatestep); icount++)
+                var updates = 0;
+                var updateStep = 0;
+                var targetTicks = Stopwatch.GetTimestamp() + UpdateTickTarget;
+                UpdateTimer.Start();
+                while (updateStep < foundSignals)
                 {
-                    SignalObject signal = SignalObjects[icount];
+                    var signal = SignalObjects[(UpdateIndex + updateStep) % foundSignals];
                     if (signal != null && !signal.noupdate) // to cater for orphans, and skip signals which do not require updates
                     {
                         signal.Update();
+                        updates++;
                     }
+                    updateStep++;
+
+                    // in preupdate, process all
+                    if (!preUpdate && updates % 10 == 0 && Stopwatch.GetTimestamp() >= targetTicks) break;
                 }
+                UpdateCounter += updates;
+                UpdateTimer.Stop();
 
-                updatecount += updatestep;
-                updatecount = updatecount >= totalSignal ? 0 : updatecount;
+                if (UpdateIndex + updateStep >= foundSignals)
+                {
+                    // Calculate how long it takes to update all signals and target 1/20th of that
+                    // Slow adjustment using clamp stops it jumping around too much
+                    var ticksPerSignal = (double)UpdateTimer.ElapsedTicks / UpdateCounter;
+                    UpdateTickTarget = (long)MathHelper.Clamp((float)(ticksPerSignal * foundSignals / 20), UpdateTickTarget - 100, UpdateTickTarget + 100);
+                    // if (++DebugUpdateCounter % 10 == 0) Trace.WriteLine($"Signal update for {UpdateCounter,5} signals took {(double)UpdateTimer.ElapsedTicks * 1000 / Stopwatch.Frequency,9:F6} ms ({ticksPerSignal * 1000 / Stopwatch.Frequency,9:F6} ms/signal); new {(double)UpdateTickTarget * 1000 / Stopwatch.Frequency,6:F6} ms target");
+                    UpdateTimer.Reset();
+                    UpdateCounter = 0;
+                }
+                UpdateIndex = (UpdateIndex + updateStep) % foundSignals;
             }
         }