[3.3] Support alt-az mounts with lateral offsets in domes

NINA.Core/Enum/MountTypeEnum.cs

@@ -30,5 +30,8 @@ public enum MountTypeEnum {
 
         [Description("LblForkOnWedge")]
         FORK_ON_WEDGE,
+
+        [Description("LblAltitudeAzimuth")]
+        ALT_AZ,
     }
 }

NINA.Core/Locale/Locale.resx

@@ -3899,7 +3899,7 @@ In case a longer duration is needed, a duration can be specified and the applica
     <value>GEM Axis Length</value>
   </data>
   <data name="LblDomeGemAxisLengthTooltip" xml:space="preserve">
-    <value>If Alt/Az, this should be 0. For an EQ mount, slew RA to +/- 90 degrees, and measure the lateral distance (in mm) from the axis to center of the telescope aperture</value>
+    <value>On an EQ mount, slew RA to +/- 90 degrees, and measure the lateral distance (in mm) from the axis to center of the telescope aperture</value>
   </data>
   <data name="LblDomeLateralAxisLength" xml:space="preserve">
     <value>Lateral Axis Length</value>
@@ -7185,6 +7185,15 @@ Additionally, it is essential that the ASCOM driver used also supports this 32-b
   <data name="LblCivilDawn" xml:space="preserve">
     <value>Civil dawn</value>
   </data>
+  <data name="LblAltitudeAzimuth" xml:space="preserve">
+    <value>Altitude-Azimuth</value>
+  </data>
+	<data name="LblDomeVerticalAxisLength" xml:space="preserve">
+    <value>Vertical axis length</value>
+  </data>
+  <data name="LblDomeVerticalAxisLengthTooltip" xml:space="preserve">
+    <value>For piggy-backed OTAs on an Alt-Az mounted telescope. This should be the distance between the center of the main OTA and the piggy-backed OTA</value>
+  </data>
   <data name="LblRefuseUnparkWithoutShutterOpen" xml:space="preserve">
     <value>Refuse mount unpark if shutter is not open</value>
   </data>

NINA.Equipment/Equipment/MyDome/DomeSynchronization.cs

@@ -24,8 +24,8 @@ This Source Code Form is subject to the terms of the Mozilla Public
 namespace NINA.Equipment.Equipment.MyDome {
 
     public class DomeSynchronization : IDomeSynchronization {
-        private static double TWO_PI = 2.0 * Math.PI;
-        private static double HALF_PI = Math.PI / 2.0;
+        private const double TWO_PI = 2.0 * Math.PI;
+        private const double HALF_PI = Math.PI / 2.0;
 
         private readonly IProfileService profileService;
 
@@ -43,7 +43,6 @@ public TopocentricCoordinates TargetDomeCoordinates(
             return TargetDomeCoordinates(scopeCoordinates: scopeCoordinates, localSiderealTime: localSiderealTime, siteLatitude: siteLatitude, siteLongitude: siteLongitude, siteElevation: 0, sideOfPier: sideOfPier);
         }
 
-
         /// <summary>
         /// Gets the dome coordinates required so the scope points directly out of the shutter. This works for Alt-Az, EQ mounts, and fork mounts on a wedge
         /// and depends on careful user measurements including:
@@ -77,16 +76,17 @@ public TopocentricCoordinates TargetDomeCoordinates(
             PierSide sideOfPier) {
             scopeCoordinates = scopeCoordinates.Transform(Epoch.JNOW);
             var domeSettings = profileService.ActiveProfile.DomeSettings;
+
             // To calculate the effect of rotations in the southern hemisphere we augment a few of the rotations to pretend as if it were the northern hemisphere,
             // and then add 180 degrees to the final result
-
             var origin = new Vector4(0, 0, 0, 1);
-            Matrix4x4 scopeOriginTranslation;
-            if (domeSettings.MountType == MountTypeEnum.EQUATORIAL) {
-                scopeOriginTranslation = CalculateGEM(scopeCoordinates, localSiderealTime, siteLatitude, sideOfPier);
-            } else {
-                scopeOriginTranslation = CalculateForkOnWedge(scopeCoordinates, localSiderealTime, siteLatitude);
-            }
+
+            var scopeOriginTranslation = domeSettings.MountType switch {
+                MountTypeEnum.EQUATORIAL => CalculateGEM(scopeCoordinates, localSiderealTime, siteLatitude, sideOfPier),
+                MountTypeEnum.FORK_ON_WEDGE => CalculateForkOnWedge(scopeCoordinates, localSiderealTime, siteLatitude),
+                MountTypeEnum.ALT_AZ => CalculateAltAz(scopeCoordinates, siteLatitude, siteLongitude),
+                _ => throw new NotSupportedException($"Unsupported mount type: {domeSettings.MountType}"),
+            };
 
             var scopeApertureOrigin = scopeOriginTranslation * origin;
 
@@ -207,5 +207,43 @@ private Matrix4x4 CalculateGEM(
 
             return mountOffset * latitudeAdjustment * raRotationAdjustment * decRotationAdjustment * gemAdjustment;
         }
+
+        private Matrix4x4 CalculateAltAz(
+            Coordinates scopeCoordinates,
+            Angle siteLatitude,
+            Angle siteLongitude) {
+            var domeSettings = profileService.ActiveProfile.DomeSettings;
+
+            // Alt-Az mounts rotate in altitude (around the y-axis) and azimuth (around the z-axis)
+            // Altitude is Dec, Azimuth is Azimuth derived from RA/Dec + LST
+
+            // Convert scope RA/Dec to horizontal coordinates (Alt/Az)
+            var topocentric = scopeCoordinates.Transform(siteLatitude, siteLongitude, 0d); // elevation not critical here
+
+            // Altitude rotation: scope tilts up from horizontal
+            var altitudeRotation = Matrix4x4.CreateRotationY((float)(topocentric.Altitude.Radians));
+
+            // Azimuth rotation: scope rotates around the dome's vertical axis (z-axis)
+            var azimuthRotation = Matrix4x4.CreateRotationZ((float)(-topocentric.Azimuth.Radians));
+
+            // Determine hemisphere direction
+            var latitudeFactor = siteLatitude.Radians >= 0 ? 1.0 : -1.0;
+
+            // Mount offset from dome center
+            var mountOffset = Matrix4x4.CreateTranslation(new Vector3(
+                (float)(domeSettings.ScopePositionNorthSouth_mm * latitudeFactor),   // X: North
+                (float)(-domeSettings.ScopePositionEastWest_mm * latitudeFactor),    // Y: East
+                (float)domeSettings.ScopePositionUpDown_mm                           // Z: Up
+            ));
+
+            // Account for any lateral axis and vertical axis offsets to accomodate side-by-side or piggyback telescopes
+            var offsets = Matrix4x4.CreateTranslation(new Vector3(
+                0.0f,
+                -(float)domeSettings.LateralAxis_mm,
+                (float)domeSettings.GemAxis_mm  // Reusing GemAxis_mm for vertical offset in Alt-Az mounts since the basic meaning is the same
+            ));
+
+            return mountOffset * (azimuthRotation * altitudeRotation * offsets);
+        }
     }
 }

NINA.Profile/DomeSettings.cs

@@ -30,12 +30,13 @@ public void OnDeserializing(StreamingContext context) {
 
         protected override void SetDefaultValues() {
             Id = "No_Device";
-            LastDeviceName = "";
+            LastDeviceName = string.Empty;
             ScopePositionEastWest_mm = 0.0;
             ScopePositionNorthSouth_mm = 0.0;
             ScopePositionUpDown_mm = 0.0;
             DomeRadius_mm = 0.0;
             GemAxis_mm = 0.0;
+            LateralAxis_mm = 0.0;
             AzimuthTolerance_degrees = 2.0;
             FindHomeBeforePark = false;
             DomeSyncTimeoutSeconds = 120;

NINA/View/Options/DomeView.xaml

@@ -152,6 +152,9 @@
                                     <DataTrigger Binding="{Binding ElementName=PART_MountTypeList, Path=SelectedItem}" Value="1">
                                         <Setter Property="Visibility" Value="Collapsed" />
                                     </DataTrigger>
+                                    <DataTrigger Binding="{Binding ElementName=PART_MountTypeList, Path=SelectedItem}" Value="2">
+                                        <Setter Property="Visibility" Value="Collapsed" />
+                                    </DataTrigger>
                                 </Style.Triggers>
                             </Style>
                         </UniformGrid.Style>
@@ -182,6 +185,9 @@
                                     <DataTrigger Binding="{Binding ElementName=PART_MountTypeList, Path=SelectedItem}" Value="0">
                                         <Setter Property="Visibility" Value="Collapsed" />
                                     </DataTrigger>
+                                    <DataTrigger Binding="{Binding ElementName=PART_MountTypeList, Path=SelectedItem}" Value="2">
+                                        <Setter Property="Visibility" Value="Collapsed" />
+                                    </DataTrigger>
                                 </Style.Triggers>
                             </Style>
                         </UniformGrid.Style>
@@ -202,6 +208,39 @@
                             Text="{Binding DecOffsetHorizontal_mm, UpdateSourceTrigger=LostFocus}"
                             Unit="mm" />
                     </UniformGrid>
+                    <UniformGrid
+                        Margin="0,5,0,0"
+                        VerticalAlignment="Center"
+                        Columns="2">
+                        <UniformGrid.Style>
+                            <Style TargetType="{x:Type UniformGrid}">
+                                <Style.Triggers>
+                                    <DataTrigger Binding="{Binding ElementName=PART_MountTypeList, Path=SelectedItem}" Value="0">
+                                        <Setter Property="Visibility" Value="Collapsed" />
+                                    </DataTrigger>
+                                    <DataTrigger Binding="{Binding ElementName=PART_MountTypeList, Path=SelectedItem}" Value="1">
+                                        <Setter Property="Visibility" Value="Collapsed" />
+                                    </DataTrigger>
+                                </Style.Triggers>
+                            </Style>
+                        </UniformGrid.Style>
+                        <TextBlock
+                            Width="250"
+                            HorizontalAlignment="Left"
+                            VerticalAlignment="Center"
+                            Text="{ns:Loc LblDomeVerticalAxisLength}">
+                            <TextBlock.ToolTip>
+                                <TextBlock Text="{ns:Loc LblDomeVerticalAxisLengthTooltip}" />
+                            </TextBlock.ToolTip>
+                        </TextBlock>
+                        <ninactrl:UnitTextBox
+                            MinWidth="80"
+                            HorizontalAlignment="Stretch"
+                            VerticalAlignment="Center"
+                            VerticalContentAlignment="Center"
+                            Text="{Binding GemAxis_mm, UpdateSourceTrigger=LostFocus}"
+                            Unit="mm" />
+                    </UniformGrid>
                     <UniformGrid
                         Margin="0,5,0,0"
                         VerticalAlignment="Center"

RELEASE_NOTES.md

@@ -30,6 +30,8 @@ More details at <a href="https://nighttime-imaging.eu/donate/" target="_blank">n
   - N.I.N.A. now queries the ASCOM device name after connecting to the driver.  
 - **ASCOM Device State**
     - For drivers that implement the new ASCOM 7 Device State the application will now use the state when possible instead of polling individual fields
+- **Domes with Alt-Az mounts**
+  - Alt-Az mounts are a new mount configuration that is supported under Options > Dome. This permits one to define mount and OTA offsets that result in proper dome azimuthal rotation for an alt-az mount, or any side-by-side or piggy-backed telescopes mounted on a main telescope.
 - ** Dome/Roof safety **
     - Optionally disallow the mount to be unparked if the dome or roof controller reports a shutter state other than Open.
 - ** Switch Polling**