Automatic merge of T1.5.1-801-g8ef12d34f and 15 pull requests

- Pull request #570 at 3539862: Experimental glTF 2.0 support with PBR lighting
- 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 b554363: Blueprint/train car operations UI window
- Pull request #885 at 8f94333: feat: Add notifications to Menu
- Pull request #886 at 6c0785b: Scene viewer extension to TrackViewer
- 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 #897 at 42f1dd9: feat: Improved system information collection
- Pull request #899 at a0a37ac: Duplex steam engines - Booster Engine addition
- Pull request #903 at 0d6d045: Downloading route content (Github, zip)
- Pull request #907 at 9b0b04f: Bug fix for https://bugs.launchpad.net/or/+bug/2047300 Dynamic tracks disappear after long tunnel
- Pull request #908 at 4b4afe3: feat: supports switching adhesion precisions
- Pull request #911 at 6834af0: docs: Add refactoring as a special type of PR
- Pull request #912 at 8106ea1: New Triple Valve Features Vol. 2

Author: openrails-bot

Source/Orts.Simulation/Simulation/RollingStocks/SubSystems/Brakes/MSTS/AirSinglePipe.cs

@@ -520,7 +520,6 @@ public override void Initialize()
                 (TwoStageSpeedUpMpS, TwoStageSpeedDownMpS) = (TwoStageSpeedDownMpS, TwoStageSpeedUpMpS);
             if (TwoStageLowPressurePSI == 0)
                 TwoStageLowPressurePSI = MaxCylPressurePSI;
-
         }
 
         /// <summary>
@@ -1165,21 +1164,21 @@ public override void Update(float elapsedClockSeconds)
                     if (loco != null)
                     {
                         float volumeRatio = CylVolumeM3 / loco.MainResVolumeM3;
-                        if (loco.MainResPressurePSI - dp * volumeRatio < CylPressurePSI + dp)
+                        if (loco.MainResPressurePSI - (dp * volumeRatio) < CylPressurePSI + dp)
                             dp = (loco.MainResPressurePSI - CylPressurePSI) / (1 + volumeRatio);
                         loco.MainResPressurePSI -= dp * volumeRatio;
                     }
                     else if (TwoPipes)
                     {
-                        if (BrakeLine2PressurePSI - dp * CylVolumeM3 / BrakePipeVolumeM3 < CylPressurePSI + dp)
-                            dp = (BrakeLine2PressurePSI - CylPressurePSI) / (1 + CylVolumeM3 / BrakePipeVolumeM3);
-                        BrakeLine2PressurePSI -= dp * CylVolumeM3 / BrakePipeVolumeM3;
+                        if (BrakeLine2PressurePSI - dp * (CylVolumeM3 / BrakePipeVolumeM3) < CylPressurePSI + dp)
+                            dp = (BrakeLine2PressurePSI - CylPressurePSI) / (1 + (CylVolumeM3 / BrakePipeVolumeM3));
+                        BrakeLine2PressurePSI -= dp * (CylVolumeM3 / BrakePipeVolumeM3);
                     }
                     CylPressurePSI += dp;
                 }
                 else if (demandedPressurePSI < CylPressurePSI)
                 {
-                    CylPressurePSI = Math.Max(Math.Max(demandedPressurePSI, CylPressurePSI - elapsedClockSeconds * RelayValveReleaseRatePSIpS), 0);
+                    CylPressurePSI = Math.Max(Math.Max(demandedPressurePSI, CylPressurePSI - (elapsedClockSeconds * RelayValveReleaseRatePSIpS)), 0);
                 }
             }
             else