Add input checking for angles.

Author: peternewell

Source/Orts.Parsers.Msts/STFReader.cs

@@ -809,6 +809,12 @@ public enum UNITS
             /// </summary>            
             Temperature = 1 << 27,    // "Temperature", note above TemperatureDifference, is different
 
+            /// <summary>
+            /// Valid Units: deg, rad
+            /// <para>Scaled to Radians</para>
+            /// </summary>            
+            Angle = 1 << 28,    // "Temperature", note above TemperatureDifference, is different
+
             // "Any" is used where units cannot easily be specified, such as generic routines for interpolating continuous data from point values.
             // or interpreting locomotive cab attributes from the ORTSExtendedCVF experimental mechanism.
             // "Any" should not be used where the dimensions of a unit are predictable.
@@ -1128,6 +1134,13 @@ internal double ParseUnitSuffix(ref string constant, UNITS validUnits)
                         return 1;
                 }
             }
+            if ((validUnits & UNITS.Angle) > 0)
+                switch (suffix)
+                {
+                    case "": return 1.0;
+                    case "rad": return 1;
+                    case "deg": return 0.0174533;  // 1 deg = 0.0174533 radians
+                }
             STFException.TraceWarning(this, "Found a suffix '" + suffix + "' which could not be parsed as a " + validUnits.ToString() + " unit");
             return 1;
         }

Source/Orts.Simulation/Simulation/RollingStocks/MSTSWagon.cs

@@ -1038,7 +1038,7 @@ public virtual void Parse(string lowercasetoken, STFReader stf)
                 case "wagon(ortshorizontallengthairhose": CarAirHoseHorizontalLengthM = stf.ReadFloatBlock(STFReader.UNITS.Distance, null); break;
                 case "wagon(ortslengthcouplerface": CarCouplerFaceLengthM = stf.ReadFloatBlock(STFReader.UNITS.Distance, null); break;
                 case "wagon(ortswheelflangelength": WheelFlangeLengthM = stf.ReadFloatBlock(STFReader.UNITS.Distance, null); break;
-                case "wagon(ortsmaximumwheelflangeangle": MaximumWheelFlangeAngleRad = stf.ReadFloatBlock(STFReader.UNITS.None, null); break;
+                case "wagon(ortsmaximumwheelflangeangle": MaximumWheelFlangeAngleRad = stf.ReadFloatBlock(STFReader.UNITS.Angle, null); break;
                 case "wagon(ortstrackgauge":
                     stf.MustMatch("(");
                     TrackGaugeM = stf.ReadFloat(STFReader.UNITS.Distance, null);