Implement letterboxing of non-fitting 2D cabs, toggleable with Ctrl+1.

Source/ORTS.Common/Input/UserCommand.cs

@@ -75,6 +75,7 @@ public enum UserCommand
         [GetString("Camera Change Passenger Viewpoint")] CameraChangePassengerViewPoint,
         [GetString("Camera 3D Cab")] CameraThreeDimensionalCab,
         [GetString("Camera Toggle Show Cab")] CameraToggleShowCab,
+        [GetString("Camera Toggle Letterbox Cab")] CameraToggleLetterboxCab,
         [GetString("Camera Head Out Forward")] CameraHeadOutForward,
         [GetString("Camera Head Out Backward")] CameraHeadOutBackward,
         [GetString("Camera Outside Front")] CameraOutsideFront,

Source/ORTS.Settings/InputSettings.cs

@@ -331,6 +331,7 @@ static void InitializeCommands(UserCommandInput[] Commands)
             Commands[(int)UserCommand.CameraScrollLeft] = new UserCommandModifiableKeyInput(0x4B, KeyModifiers.Alt);
             Commands[(int)UserCommand.CameraScrollRight] = new UserCommandModifiableKeyInput(0x4D, KeyModifiers.Alt);
             Commands[(int)UserCommand.CameraChangePassengerViewPoint] = new UserCommandKeyInput(0x06, KeyModifiers.Shift);
+            Commands[(int)UserCommand.CameraToggleLetterboxCab] = new UserCommandKeyInput(0x02, KeyModifiers.Control);
             Commands[(int)UserCommand.CameraToggleShowCab] = new UserCommandKeyInput(0x02, KeyModifiers.Shift);
             Commands[(int)UserCommand.CameraTrackside] = new UserCommandKeyInput(0x05);
             Commands[(int)UserCommand.CameraSpecialTracksidePoint] = new UserCommandKeyInput(0x05, KeyModifiers.Shift);

Source/ORTS.Settings/UserSettings.cs

@@ -339,6 +339,8 @@ public enum Menu_SelectionIndex
         [Default(false)]
         public bool DataLogger { get; set; }
         [Default(false)]
+        public bool Letterbox2DCab { get; set; }
+        [Default(false)]
         public bool Profiling { get; set; }
         [Default(0)]
         public int ProfilingFrameCount { get; set; }

Source/RunActivity/Viewer3D/Cameras.cs

@@ -2198,6 +2198,11 @@ public override void HandleUserInput(ElapsedTime elapsedTime)
                 ScrollRight(true, speed);
             if (UserInput.IsDown(UserCommand.CameraScrollLeft))
                 ScrollRight(false, speed);
+            if (UserInput.IsPressed(UserCommand.CameraToggleLetterboxCab))
+            {
+                Viewer.Settings.Letterbox2DCab = !Viewer.Settings.Letterbox2DCab;
+                Viewer.AdjustCabHeight(Viewer.DisplaySize.X, Viewer.DisplaySize.Y);
+            }
         }
     }
 

Source/RunActivity/Viewer3D/RollingStock/MSTSLocomotiveViewer.cs

@@ -1282,6 +1282,10 @@ public void PrepareFrame(RenderFrame frame, ElapsedTime elapsedTime)
             _CabRect.Width = _Viewer.CabWidthPixels;
             _CabRect.Height = _Viewer.CabHeightPixels;
 
+            // Cab view position adjusted to allow for letterboxing
+            _CabRect.X = _Viewer.CabXLetterboxPixels;
+            _CabRect.Y = _Viewer.CabYLetterboxPixels;
+
             if (_PrevScreenSize != _Viewer.DisplaySize && _Shader != null)
             {
                 _PrevScreenSize = _Viewer.DisplaySize;
@@ -1335,6 +1339,24 @@ public override void Draw(GraphicsDevice graphicsDevice)
                 {
                     _SpriteShader2DCabView.SpriteBatch.Draw(_CabTexture, stretchedCab, Color.White);
                 }
+
+                // Draw letterboxing.
+                Texture2D letterboxTexture = new Texture2D(graphicsDevice, 1, 1);
+                letterboxTexture.SetData<Color>(new Color[] { Color.Black });
+                Action<int, int, int, int> drawLetterbox = (x, y, w, h) =>
+                {
+                    _SpriteShader2DCabView.SpriteBatch.Draw(letterboxTexture, new Rectangle(x, y, w, h), Color.White);
+                };
+                if (_Viewer.CabXLetterboxPixels > 0)
+                {
+                    drawLetterbox(0, 0, _Viewer.CabXLetterboxPixels, _Viewer.DisplaySize.Y);
+                    drawLetterbox(_Viewer.CabXLetterboxPixels + _Viewer.CabWidthPixels, 0, _Viewer.DisplaySize.X - _Viewer.CabWidthPixels - _Viewer.CabXLetterboxPixels, _Viewer.DisplaySize.Y);
+                }
+                if (_Viewer.CabYLetterboxPixels > 0)
+                {
+                    drawLetterbox(0, 0, _Viewer.DisplaySize.X, _Viewer.CabYLetterboxPixels);
+                    drawLetterbox(0, _Viewer.CabYLetterboxPixels + _Viewer.CabHeightPixels, _Viewer.DisplaySize.X, _Viewer.DisplaySize.Y - _Viewer.CabHeightPixels - _Viewer.CabYLetterboxPixels);
+                }
             }
         }
 
@@ -1463,7 +1485,11 @@ public override void PrepareFrame(RenderFrame frame, ElapsedTime elapsedTime)
             // Cab view height and vertical position adjusted to allow for clip or stretch.
             Position.X = (float)Viewer.CabWidthPixels / 640 * ((float)Control.PositionX + Origin.X * Scale) - Viewer.CabXOffsetPixels;
             Position.Y = (float)Viewer.CabHeightPixels / 480 * ((float)Control.PositionY + Origin.Y * Scale) + Viewer.CabYOffsetPixels;
-            ScaleToScreen = (float)Viewer.DisplaySize.X / 640 * Scale;
+            ScaleToScreen = (float)Viewer.CabWidthPixels / 640 * Scale;
+
+            // Cab view position adjusted to allow for letterboxing.
+            Position.X += Viewer.CabXLetterboxPixels;
+            Position.Y += Viewer.CabYLetterboxPixels;
 
             var rangeFraction = GetRangeFraction();
             var direction = ControlDial.Direction == 0 ? 1 : -1;
@@ -1650,6 +1676,10 @@ public override void PrepareFrame(RenderFrame frame, ElapsedTime elapsedTime)
                     else DrawColor = new Color(Gauge.PositiveColor.R, Gauge.PositiveColor.G, Gauge.PositiveColor.B, Gauge.PositiveColor.A);
                 }
             }
+
+            // Cab view position adjusted to allow for letterboxing.
+            DestinationRectangle.X += Viewer.CabXLetterboxPixels;
+            DestinationRectangle.Y += Viewer.CabYLetterboxPixels;
         }
 
         public override void Draw(GraphicsDevice graphicsDevice)
@@ -1739,6 +1769,10 @@ public override void PrepareFrame(RenderFrame frame, ElapsedTime elapsedTime)
             DestinationRectangle.Y = (int)(yratio * Control.PositionY * 1.0001) + Viewer.CabYOffsetPixels;
             DestinationRectangle.Width = (int)(xratio * Math.Min(Control.Width, Texture.Width));  // Allow only downscaling of the texture, and not upscaling
             DestinationRectangle.Height = (int)(yratio * Math.Min(Control.Height, Texture.Height));  // Allow only downscaling of the texture, and not upscaling
+
+            // Cab view position adjusted to allow for letterboxing.
+            DestinationRectangle.X += Viewer.CabXLetterboxPixels;
+            DestinationRectangle.Y += Viewer.CabYLetterboxPixels;
         }
 
         public override void Draw(GraphicsDevice graphicsDevice)
@@ -2117,6 +2151,10 @@ public override void PrepareFrame(RenderFrame frame, ElapsedTime elapsedTime)
             DrawPosition.Width = (int)(Control.Width * Viewer.DisplaySize.X / 640);
             DrawPosition.Height = (int)(Control.Height * Viewer.DisplaySize.Y / 480);
 
+            // Cab view position adjusted to allow for letterboxing.
+            DrawPosition.X += Viewer.CabXLetterboxPixels;
+            DrawPosition.Y += Viewer.CabYLetterboxPixels;
+
             if (Control.ControlType == CABViewControlTypes.CLOCK)
             {
                 // Clock is drawn specially.

Source/RunActivity/Viewer3D/Viewer.cs

@@ -169,9 +169,10 @@ enum VisibilityState
 
         // MSTS cab views are images with aspect ratio 4:3.
         // OR can use cab views with other aspect ratios where these are available.
-        // On screen with other aspect ratios (e.g. 16:9), two approaches are possible:
+        // On screen with other aspect ratios (e.g. 16:9), three approaches are possible:
         //   1) stretch the width to fit the screen. This gives flattened controls, most noticeable with round dials.
         //   2) clip the image losing a slice off top and bottom.
+        //   3) letterbox the image by drawing black bars in the unfilled spaces.
         // Setting.Cab2DStretch controls the amount of stretch and clip. 0 is entirely clipped and 100 is entirely stretched.
         // No difference is seen on screens with 4:3 aspect ratio.
         // This adjustment assumes that the cab view is 4:3. Where the cab view matches the aspect ratio of the screen, use an adjustment of 100.
@@ -181,6 +182,8 @@ enum VisibilityState
         public int CabXOffsetPixels { get; set; }
         public int CabExceedsDisplay; // difference between cabview texture vertical resolution and display vertical resolution
         public int CabExceedsDisplayHorizontally; // difference between cabview texture horizontal resolution and display vertical resolution
+        public int CabYLetterboxPixels { get; set; } // offset the cab when drawing it if it is smaller than the display; both coordinates should always be >= 0
+        public int CabXLetterboxPixels { get; set; }
         public float CabTextureInverseRatio = 0.75f; // default of inverse of cab texture ratio 
 
         public CommandLog Log { get { return Simulator.Log; } }
@@ -618,28 +621,41 @@ public void AdjustCabHeight(int windowWidth, int windowHeight)
             }
             int unstretchedCabHeightPixels = (int)(CabTextureInverseRatio * windowWidth);
             int unstretchedCabWidthPixels = (int)(windowHeight / CabTextureInverseRatio);
-            if (((float)windowHeight / windowWidth) < CabTextureInverseRatio)
+            float windowInverseRatio = (float)windowHeight / windowWidth;
+            if (Settings.Letterbox2DCab)
             {
-                // screen is wide-screen, so can choose between vertical scroll or horizontal stretch
-                CabExceedsDisplay = (int)((unstretchedCabHeightPixels - windowHeight) * ((100 - Settings.Cab2DStretch) / 100f));
-                CabExceedsDisplayHorizontally = 0;
-            }
-            else if (((float)windowHeight / windowWidth) > CabTextureInverseRatio)
-            {
-                // must scroll horizontally
-                CabExceedsDisplay = 0;
-                CabExceedsDisplayHorizontally = unstretchedCabWidthPixels - windowWidth;
+                CabWidthPixels = Math.Min((int)Math.Round(windowHeight / CabTextureInverseRatio), windowWidth);
+                CabHeightPixels = Math.Min((int)Math.Round(windowWidth * CabTextureInverseRatio), windowHeight);
+                CabXLetterboxPixels = (windowWidth - CabWidthPixels) / 2;
+                CabYLetterboxPixels = (windowHeight - CabHeightPixels) / 2;
+                CabExceedsDisplay = CabExceedsDisplayHorizontally = CabXOffsetPixels = CabYOffsetPixels = 0;
             }
             else
             {
-                // nice, window aspect ratio and cabview aspect ratio are identical
-                CabExceedsDisplay = 0;
-                CabExceedsDisplayHorizontally = 0;
+                if (windowInverseRatio == CabTextureInverseRatio)
+                {
+                    // nice, window aspect ratio and cabview aspect ratio are identical
+                    CabExceedsDisplay = 0;
+                    CabExceedsDisplayHorizontally = 0;
+                }
+                else if (windowInverseRatio < CabTextureInverseRatio)
+                {
+                    // screen is wide-screen, so can choose between vertical scroll or horizontal stretch
+                    CabExceedsDisplay = (int)((unstretchedCabHeightPixels - windowHeight) * ((100 - Settings.Cab2DStretch) / 100f));
+                    CabExceedsDisplayHorizontally = 0;
+                }
+                else
+                {
+                    // must scroll horizontally
+                    CabExceedsDisplay = 0;
+                    CabExceedsDisplayHorizontally = unstretchedCabWidthPixels - windowWidth;
+                }
+                CabHeightPixels = windowHeight + CabExceedsDisplay;
+                CabYOffsetPixels = -CabExceedsDisplay / 2; // Initial value is halfway. User can adjust with arrow keys.
+                CabWidthPixels = windowWidth + CabExceedsDisplayHorizontally;
+                CabXOffsetPixels = CabExceedsDisplayHorizontally / 2;
+                CabXLetterboxPixels = CabYLetterboxPixels = 0;
             }
-            CabHeightPixels = windowHeight + CabExceedsDisplay;
-            CabYOffsetPixels = -CabExceedsDisplay / 2; // Initial value is halfway. User can adjust with arrow keys.
-            CabWidthPixels = windowWidth + CabExceedsDisplayHorizontally;
-            CabXOffsetPixels = CabExceedsDisplayHorizontally / 2;
             if (CabCamera.IsAvailable) CabCamera.Initialize();
         }