From b4e81cb8f22b4856a42f3fe4f85e895a57bea02e Mon Sep 17 00:00:00 2001
From: slarticodefast <161409025+slarticodefast@users.noreply.github.com>
Date: Fri, 25 Jul 2025 18:53:01 +0200
Subject: [PATCH] Admin Tool: Observe entities in an extra viewport (#36969)

* camera

* add console command

* change verb name to camera

* placeholder text

* add button to player panel

* orks are indeed the best

* visibility flag fix

* not a datafield

* more follower fixes

* more cleanup

* add zooming

* resizing real

* remove commented out code

* remove AddForceSend

* comment

* Use OS window and add some comments

* fix comments and variable name

* Needs RT update

* Minor grammarchange

* Fix warning

* Cleanup

* almost working...

* fix bug

* oswindow update

* Remove need for RequestClosed.

---------

Co-authored-by: beck-thompson <beck314159@hotmail.com>
Co-authored-by: PJB3005 <pieterjan.briers+git@gmail.com>
---
 .../UI/AdminCamera/AdminCameraControl.xaml    |  20 +++
 .../UI/AdminCamera/AdminCameraControl.xaml.cs | 101 +++++++++++++++
 .../UI/AdminCamera/AdminCameraEui.cs          | 117 ++++++++++++++++++
 .../UI/AdminCamera/AdminCameraWindow.xaml     |   6 +
 .../UI/AdminCamera/AdminCameraWindow.xaml.cs  |  23 ++++
 .../UI/PlayerPanel/PlayerPanel.xaml           |   1 +
 .../UI/PlayerPanel/PlayerPanel.xaml.cs        |  41 +++---
 .../UI/PlayerPanel/PlayerPanelEui.cs          |   5 +-
 .../Administration/Commands/CameraCommand.cs  |  58 +++++++++
 .../Administration/Systems/AdminVerbSystem.cs |  16 +++
 .../Administration/UI/AdminCameraEui.cs       |  97 +++++++++++++++
 .../Administration/AdminCameraEuiState.cs     |  27 ++++
 Content.Shared/Eye/VisibilityFlags.cs         |   7 +-
 Content.Shared/Follower/FollowerSystem.cs     |   3 +
 .../en-US/administration/admin-verbs.ftl      |   2 +
 .../en-US/administration/commands/camera.ftl  |   5 +
 .../administration/ui/admin-camera-window.ftl |   5 +
 .../en-US/administration/ui/player-panel.ftl  |   1 +
 .../Entities/Interface/admin_tools.yml        |  14 +++
 19 files changed, 525 insertions(+), 24 deletions(-)
 create mode 100644 Content.Client/Administration/UI/AdminCamera/AdminCameraControl.xaml
 create mode 100644 Content.Client/Administration/UI/AdminCamera/AdminCameraControl.xaml.cs
 create mode 100644 Content.Client/Administration/UI/AdminCamera/AdminCameraEui.cs
 create mode 100644 Content.Client/Administration/UI/AdminCamera/AdminCameraWindow.xaml
 create mode 100644 Content.Client/Administration/UI/AdminCamera/AdminCameraWindow.xaml.cs
 create mode 100644 Content.Server/Administration/Commands/CameraCommand.cs
 create mode 100644 Content.Server/Administration/UI/AdminCameraEui.cs
 create mode 100644 Content.Shared/Administration/AdminCameraEuiState.cs
 create mode 100644 Resources/Locale/en-US/administration/commands/camera.ftl
 create mode 100644 Resources/Locale/en-US/administration/ui/admin-camera-window.ftl
 create mode 100644 Resources/Prototypes/Entities/Interface/admin_tools.yml

diff --git a/Content.Client/Administration/UI/AdminCamera/AdminCameraControl.xaml b/Content.Client/Administration/UI/AdminCamera/AdminCameraControl.xaml
new file mode 100644
index 0000000000..1413eff00c
--- /dev/null
+++ b/Content.Client/Administration/UI/AdminCamera/AdminCameraControl.xaml
@@ -0,0 +1,20 @@
+<Control
+    xmlns="https://spacestation14.io"
+    xmlns:viewport="clr-namespace:Content.Client.Viewport"
+    MouseFilter="Stop">
+    <PanelContainer StyleClasses="BackgroundDark" Name="AdminCameraWindowRoot" Access="Public">
+        <BoxContainer Orientation="Vertical" Access="Public">
+            <!-- Camera -->
+            <Control VerticalExpand="True" Name="CameraViewBox">
+                <viewport:ScalingViewport Name="CameraView"
+                                          MinSize="100 100"
+                                          MouseFilter="Ignore" />
+            </Control>
+            <!-- Controller buttons -->
+            <BoxContainer Orientation="Horizontal" Margin="5 5 5 5">
+                <Button StyleClasses="OpenRight" Name="FollowButton" HorizontalExpand="True" Access="Public" Text="{Loc 'admin-camera-window-follow'}" />
+                <Button StyleClasses="OpenLeft" Name="PopControl" HorizontalExpand="True" Access="Public" Text="{Loc 'admin-camera-window-pop-out'}" />
+            </BoxContainer>
+        </BoxContainer>
+    </PanelContainer>
+</Control>
diff --git a/Content.Client/Administration/UI/AdminCamera/AdminCameraControl.xaml.cs b/Content.Client/Administration/UI/AdminCamera/AdminCameraControl.xaml.cs
new file mode 100644
index 0000000000..beb8344ce3
--- /dev/null
+++ b/Content.Client/Administration/UI/AdminCamera/AdminCameraControl.xaml.cs
@@ -0,0 +1,101 @@
+using System.Numerics;
+using Content.Client.Eye;
+using Content.Shared.Administration;
+using Robust.Client.AutoGenerated;
+using Robust.Client.Graphics;
+using Robust.Client.Timing;
+using Robust.Client.UserInterface;
+using Robust.Client.UserInterface.XAML;
+using Robust.Shared.Timing;
+
+namespace Content.Client.Administration.UI.AdminCamera;
+
+[GenerateTypedNameReferences]
+public sealed partial class AdminCameraControl : Control
+{
+    [Dependency] private readonly IEntityManager _entManager = default!;
+    [Dependency] private readonly IClientGameTiming _timing = default!;
+
+    public event Action? OnFollow;
+    public event Action? OnPopoutControl;
+
+    private readonly EyeLerpingSystem _eyeLerpingSystem;
+    private readonly FixedEye _defaultEye = new();
+    private AdminCameraEuiState? _nextState;
+
+    private const float MinimumZoom = 0.1f;
+    private const float MaximumZoom = 2.0f;
+
+    public EntityUid? CurrentCamera;
+    public float Zoom = 1.0f;
+
+    public bool IsPoppedOut;
+
+    public AdminCameraControl()
+    {
+        RobustXamlLoader.Load(this);
+        IoCManager.InjectDependencies(this);
+
+        _eyeLerpingSystem = _entManager.System<EyeLerpingSystem>();
+
+        CameraView.Eye = _defaultEye;
+
+        FollowButton.OnPressed += _ => OnFollow?.Invoke();
+        PopControl.OnPressed += _ => OnPopoutControl?.Invoke();
+        CameraView.OnResized += OnResized;
+    }
+
+    private new void OnResized()
+    {
+        var width = Math.Max(CameraView.PixelWidth, (int)Math.Floor(CameraView.MinWidth));
+        var height = Math.Max(CameraView.PixelHeight, (int)Math.Floor(CameraView.MinHeight));
+
+        CameraView.ViewportSize = new Vector2i(width, height);
+    }
+
+    protected override void MouseWheel(GUIMouseWheelEventArgs args)
+    {
+        base.MouseWheel(args);
+
+        if (CameraView.Eye == null)
+            return;
+
+        Zoom = Math.Clamp(Zoom - args.Delta.Y * 0.15f * Zoom, MinimumZoom, MaximumZoom);
+        CameraView.Eye.Zoom = new Vector2(Zoom, Zoom);
+        args.Handle();
+    }
+
+    public void SetState(AdminCameraEuiState state)
+    {
+        _nextState = state;
+    }
+
+    // I know that this is awful, but I copied this from the solution editor anyways.
+    // This is needed because EUIs update before the gamestate is applied, which means it will fail to get the uid from the net entity.
+    // The suggestion from the comment in the solution editor saying to use a BUI is not ideal either:
+    // - We would need to bind the UI to an entity, but with how BUIs currently work we cannot open it in the same tick as we spawn that entity on the server.
+    // - We want the UI opened by the user session, not by their currently attached entity. Otherwise it would close in cases where admins move from one entity to another, for example when ghosting.
+    protected override void FrameUpdate(FrameEventArgs args)
+    {
+        if (_nextState == null || _timing.LastRealTick < _nextState.Tick) // make sure the last gamestate has been applied
+            return;
+
+        if (!_entManager.TryGetEntity(_nextState.Camera, out var cameraUid))
+            return;
+
+        if (CurrentCamera == null)
+        {
+            _eyeLerpingSystem.AddEye(cameraUid.Value);
+            CurrentCamera = cameraUid;
+        }
+        else if (CurrentCamera != cameraUid)
+        {
+            _eyeLerpingSystem.RemoveEye(CurrentCamera.Value);
+            _eyeLerpingSystem.AddEye(cameraUid.Value);
+            CurrentCamera = cameraUid;
+        }
+
+        if (_entManager.TryGetComponent<EyeComponent>(CurrentCamera, out var eye))
+            CameraView.Eye = eye.Eye ?? _defaultEye;
+    }
+}
diff --git a/Content.Client/Administration/UI/AdminCamera/AdminCameraEui.cs b/Content.Client/Administration/UI/AdminCamera/AdminCameraEui.cs
new file mode 100644
index 0000000000..908fb2740c
--- /dev/null
+++ b/Content.Client/Administration/UI/AdminCamera/AdminCameraEui.cs
@@ -0,0 +1,117 @@
+using System.Numerics;
+using Content.Client.Eui;
+using Content.Shared.Administration;
+using Content.Shared.Eui;
+using JetBrains.Annotations;
+using Robust.Client.UserInterface.Controls;
+
+namespace Content.Client.Administration.UI.AdminCamera;
+
+/// <summary>
+/// Admin Eui for opening a viewport window to observe entities.
+/// Use the "Open Camera" admin verb or the "camera" command to open.
+/// </summary>
+[UsedImplicitly]
+public sealed partial class AdminCameraEui : BaseEui
+{
+    private readonly AdminCameraWindow _window;
+    private readonly AdminCameraControl _control;
+
+    // If not null the camera is in "popped out" mode and is in an external window.
+    private OSWindow? _OSWindow;
+
+    // The last location the window was located at in game.
+    // Is used for getting knowing where to "pop in" external windows.
+    private Vector2 _lastLocation;
+
+    public AdminCameraEui()
+    {
+        _window = new AdminCameraWindow();
+        _control = new AdminCameraControl();
+
+        _window.Contents.AddChild(_control);
+
+        _control.OnFollow += () => SendMessage(new AdminCameraFollowMessage());
+        _window.OnClose += () =>
+        {
+            if (!_control.IsPoppedOut)
+                SendMessage(new CloseEuiMessage());
+        };
+
+        _control.OnPopoutControl += () =>
+        {
+            if (_control.IsPoppedOut)
+                PopIn();
+            else
+                PopOut();
+        };
+    }
+
+    // Pop the window out into an external OS window
+    private void PopOut()
+    {
+        _lastLocation = _window.Position;
+
+        // TODO: When there is a way to have a minimum window size, enforce something!
+        _OSWindow = new OSWindow
+        {
+            SetSize = _window.Size,
+            Title = _window.Title ?? Loc.GetString("admin-camera-window-title-placeholder"),
+        };
+
+        _OSWindow.Show();
+
+        if (_OSWindow.Root == null)
+            return;
+
+        _control.Orphan();
+        _OSWindow.Root.AddChild(_control);
+
+        _OSWindow.Closed += () =>
+        {
+            if (_control.IsPoppedOut)
+                SendMessage(new CloseEuiMessage());
+        };
+
+        _control.IsPoppedOut = true;
+        _control.PopControl.Text = Loc.GetString("admin-camera-window-pop-in");
+
+        _window.Close();
+    }
+
+    // Pop the window back into the in game window.
+    private void PopIn()
+    {
+        _control.Orphan();
+        _window.Contents.AddChild(_control);
+
+        _window.Open(_lastLocation);
+
+        _control.IsPoppedOut = false;
+        _control.PopControl.Text = Loc.GetString("admin-camera-window-pop-out");
+
+        _OSWindow?.Close();
+        _OSWindow = null;
+    }
+
+    public override void Opened()
+    {
+        base.Opened();
+        _window.OpenCentered();
+    }
+
+    public override void Closed()
+    {
+        base.Closed();
+        _window.Close();
+    }
+
+    public override void HandleState(EuiStateBase baseState)
+    {
+        if (baseState is not AdminCameraEuiState state)
+            return;
+
+        _window.SetState(state);
+        _control.SetState(state);
+    }
+}
diff --git a/Content.Client/Administration/UI/AdminCamera/AdminCameraWindow.xaml b/Content.Client/Administration/UI/AdminCamera/AdminCameraWindow.xaml
new file mode 100644
index 0000000000..87583cef97
--- /dev/null
+++ b/Content.Client/Administration/UI/AdminCamera/AdminCameraWindow.xaml
@@ -0,0 +1,6 @@
+<DefaultWindow xmlns="https://spacestation14.io"
+    Title="{Loc admin-camera-window-title-placeholder}"
+    SetSize="425 550"
+    MinSize="200 225"
+    Name="Window">
+</DefaultWindow>
diff --git a/Content.Client/Administration/UI/AdminCamera/AdminCameraWindow.xaml.cs b/Content.Client/Administration/UI/AdminCamera/AdminCameraWindow.xaml.cs
new file mode 100644
index 0000000000..07a6e2156e
--- /dev/null
+++ b/Content.Client/Administration/UI/AdminCamera/AdminCameraWindow.xaml.cs
@@ -0,0 +1,23 @@
+using Content.Shared.Administration;
+using Robust.Client.AutoGenerated;
+using Robust.Client.UserInterface.CustomControls;
+using Robust.Client.UserInterface.XAML;
+
+namespace Content.Client.Administration.UI.AdminCamera;
+
+[GenerateTypedNameReferences]
+public sealed partial class AdminCameraWindow : DefaultWindow
+{
+    public AdminCameraWindow()
+    {
+        RobustXamlLoader.Load(this);
+        IoCManager.InjectDependencies(this);
+
+        ContentsContainer.Margin = new Thickness(5, 0, 5, 0);
+    }
+
+    public void SetState(AdminCameraEuiState state)
+    {
+        Title = Loc.GetString("admin-camera-window-title", ("name", state.Name));
+    }
+}
diff --git a/Content.Client/Administration/UI/PlayerPanel/PlayerPanel.xaml b/Content.Client/Administration/UI/PlayerPanel/PlayerPanel.xaml
index 4791dcf6aa..9c54049da3 100644
--- a/Content.Client/Administration/UI/PlayerPanel/PlayerPanel.xaml
+++ b/Content.Client/Administration/UI/PlayerPanel/PlayerPanel.xaml
@@ -31,6 +31,7 @@
             <Button Name="FreezeAndMuteToggleButton" Text="{Loc player-panel-freeze-and-mute}" Disabled="True"/>
             <Button Name="BanButton" Text="{Loc player-panel-ban}" Disabled="True"/>
             <controls:ConfirmButton Name="RejuvenateButton" Text="{Loc player-panel-rejuvenate}" Disabled="True"/>
+            <Button Name="CameraButton" Text="{Loc player-panel-camera}" Disabled="True"/>
            </GridContainer>
        </BoxContainer>
     </BoxContainer>
diff --git a/Content.Client/Administration/UI/PlayerPanel/PlayerPanel.xaml.cs b/Content.Client/Administration/UI/PlayerPanel/PlayerPanel.xaml.cs
index 14311851b4..62cb64050e 100644
--- a/Content.Client/Administration/UI/PlayerPanel/PlayerPanel.xaml.cs
+++ b/Content.Client/Administration/UI/PlayerPanel/PlayerPanel.xaml.cs
@@ -18,6 +18,7 @@ public sealed partial class PlayerPanel : FancyWindow
     public event Action<NetUserId?>? OnOpenBans;
     public event Action<NetUserId?>? OnAhelp;
     public event Action<string?>? OnKick;
+    public event Action<string?>? OnCamera;
     public event Action<NetUserId?>? OnOpenBanPanel;
     public event Action<NetUserId?, bool>? OnWhitelistToggle;
     public event Action? OnFollow;
@@ -33,26 +34,27 @@ public sealed partial class PlayerPanel : FancyWindow
 
     public PlayerPanel(IClientAdminManager adminManager)
     {
-            RobustXamlLoader.Load(this);
-            _adminManager = adminManager;
+        RobustXamlLoader.Load(this);
+        _adminManager = adminManager;
 
-            UsernameCopyButton.OnPressed += _ => OnUsernameCopy?.Invoke(TargetUsername ?? "");
-            BanButton.OnPressed += _ => OnOpenBanPanel?.Invoke(TargetPlayer);
-            KickButton.OnPressed += _ => OnKick?.Invoke(TargetUsername);
-            NotesButton.OnPressed += _ => OnOpenNotes?.Invoke(TargetPlayer);
-            ShowBansButton.OnPressed += _ => OnOpenBans?.Invoke(TargetPlayer);
-            AhelpButton.OnPressed += _ => OnAhelp?.Invoke(TargetPlayer);
-            WhitelistToggle.OnPressed += _ =>
-            {
-                OnWhitelistToggle?.Invoke(TargetPlayer, _isWhitelisted);
-                SetWhitelisted(!_isWhitelisted);
-            };
-            FollowButton.OnPressed += _ => OnFollow?.Invoke();
-            FreezeButton.OnPressed += _ => OnFreeze?.Invoke();
-            FreezeAndMuteToggleButton.OnPressed += _ => OnFreezeAndMuteToggle?.Invoke();
-            LogsButton.OnPressed += _ => OnLogs?.Invoke();
-            DeleteButton.OnPressed += _ => OnDelete?.Invoke();
-            RejuvenateButton.OnPressed += _ => OnRejuvenate?.Invoke();
+        UsernameCopyButton.OnPressed += _ => OnUsernameCopy?.Invoke(TargetUsername ?? "");
+        BanButton.OnPressed += _ => OnOpenBanPanel?.Invoke(TargetPlayer);
+        KickButton.OnPressed += _ => OnKick?.Invoke(TargetUsername);
+        CameraButton.OnPressed += _ => OnCamera?.Invoke(TargetUsername);
+        NotesButton.OnPressed += _ => OnOpenNotes?.Invoke(TargetPlayer);
+        ShowBansButton.OnPressed += _ => OnOpenBans?.Invoke(TargetPlayer);
+        AhelpButton.OnPressed += _ => OnAhelp?.Invoke(TargetPlayer);
+        WhitelistToggle.OnPressed += _ =>
+        {
+            OnWhitelistToggle?.Invoke(TargetPlayer, _isWhitelisted);
+            SetWhitelisted(!_isWhitelisted);
+        };
+        FollowButton.OnPressed += _ => OnFollow?.Invoke();
+        FreezeButton.OnPressed += _ => OnFreeze?.Invoke();
+        FreezeAndMuteToggleButton.OnPressed += _ => OnFreezeAndMuteToggle?.Invoke();
+        LogsButton.OnPressed += _ => OnLogs?.Invoke();
+        DeleteButton.OnPressed += _ => OnDelete?.Invoke();
+        RejuvenateButton.OnPressed += _ => OnRejuvenate?.Invoke();
     }
 
     public void SetUsername(string player)
@@ -122,6 +124,7 @@ public sealed partial class PlayerPanel : FancyWindow
     {
         BanButton.Disabled = !_adminManager.CanCommand("banpanel");
         KickButton.Disabled = !_adminManager.CanCommand("kick");
+        CameraButton.Disabled = !_adminManager.CanCommand("camera");
         NotesButton.Disabled = !_adminManager.CanCommand("adminnotes");
         ShowBansButton.Disabled = !_adminManager.CanCommand("banlist");
         WhitelistToggle.Disabled =
diff --git a/Content.Client/Administration/UI/PlayerPanel/PlayerPanelEui.cs b/Content.Client/Administration/UI/PlayerPanel/PlayerPanelEui.cs
index 2129fa5b0c..8c8183ef22 100644
--- a/Content.Client/Administration/UI/PlayerPanel/PlayerPanelEui.cs
+++ b/Content.Client/Administration/UI/PlayerPanel/PlayerPanelEui.cs
@@ -15,7 +15,7 @@ public sealed class PlayerPanelEui : BaseEui
     [Dependency] private readonly IClientAdminManager _admin = default!;
     [Dependency] private readonly IClipboardManager _clipboard = default!;
 
-    private PlayerPanel PlayerPanel { get;  }
+    private PlayerPanel PlayerPanel { get; }
 
     public PlayerPanelEui()
     {
@@ -25,6 +25,7 @@ public sealed class PlayerPanelEui : BaseEui
         PlayerPanel.OnOpenNotes += id => _console.ExecuteCommand($"adminnotes \"{id}\"");
         // Kick command does not support GUIDs
         PlayerPanel.OnKick += username => _console.ExecuteCommand($"kick \"{username}\"");
+        PlayerPanel.OnCamera += username => _console.ExecuteCommand($"camera \"{username}\"");
         PlayerPanel.OnOpenBanPanel += id => _console.ExecuteCommand($"banpanel \"{id}\"");
         PlayerPanel.OnOpenBans += id => _console.ExecuteCommand($"banlist \"{id}\"");
         PlayerPanel.OnAhelp += id => _console.ExecuteCommand($"openahelp \"{id}\"");
@@ -37,7 +38,7 @@ public sealed class PlayerPanelEui : BaseEui
         PlayerPanel.OnFreeze += () => SendMessage(new PlayerPanelFreezeMessage());
         PlayerPanel.OnLogs += () => SendMessage(new PlayerPanelLogsMessage());
         PlayerPanel.OnRejuvenate += () => SendMessage(new PlayerPanelRejuvenationMessage());
-        PlayerPanel.OnDelete+= () => SendMessage(new PlayerPanelDeleteMessage());
+        PlayerPanel.OnDelete += () => SendMessage(new PlayerPanelDeleteMessage());
         PlayerPanel.OnFollow += () => SendMessage(new PlayerPanelFollowMessage());
 
         PlayerPanel.OnClose += () => SendMessage(new CloseEuiMessage());
diff --git a/Content.Server/Administration/Commands/CameraCommand.cs b/Content.Server/Administration/Commands/CameraCommand.cs
new file mode 100644
index 0000000000..25837ac709
--- /dev/null
+++ b/Content.Server/Administration/Commands/CameraCommand.cs
@@ -0,0 +1,58 @@
+using Content.Server.Administration.UI;
+using Content.Server.EUI;
+using Content.Shared.Administration;
+using Robust.Server.Player;
+using Robust.Shared.Console;
+
+namespace Content.Server.Administration.Commands;
+
+[AdminCommand(AdminFlags.Admin)]
+public sealed class CameraCommand : LocalizedCommands
+{
+    [Dependency] private readonly EuiManager _eui = default!;
+    [Dependency] private readonly IEntityManager _entManager = default!;
+    [Dependency] private readonly IPlayerManager _playerManager = default!;
+
+    public override string Command => "camera";
+
+    public override void Execute(IConsoleShell shell, string argStr, string[] args)
+    {
+        if (shell.Player is not { } user)
+        {
+            shell.WriteError(Loc.GetString("shell-cannot-run-command-from-server"));
+            return;
+        }
+
+        if (args.Length != 1)
+        {
+            shell.WriteError(Loc.GetString("shell-wrong-arguments-number"));
+            return;
+        }
+
+        if (!NetEntity.TryParse(args[0], out var targetNetId) || !_entManager.TryGetEntity(targetNetId, out var targetUid))
+        {
+            if (!_playerManager.TryGetSessionByUsername(args[0], out var player)
+                || player.AttachedEntity == null)
+            {
+                shell.WriteError(Loc.GetString("cmd-camera-wrong-argument"));
+                return;
+            }
+            targetUid = player.AttachedEntity.Value;
+        }
+
+        var ui = new AdminCameraEui(targetUid.Value);
+        _eui.OpenEui(ui, user);
+    }
+
+    public override CompletionResult GetCompletion(IConsoleShell shell, string[] args)
+    {
+        if (args.Length == 1)
+        {
+            return CompletionResult.FromHintOptions(
+                CompletionHelper.SessionNames(players: _playerManager),
+                Loc.GetString("cmd-camera-hint"));
+        }
+
+        return CompletionResult.Empty;
+    }
+}
diff --git a/Content.Server/Administration/Systems/AdminVerbSystem.cs b/Content.Server/Administration/Systems/AdminVerbSystem.cs
index 19bcfd26f6..61e3013bd9 100644
--- a/Content.Server/Administration/Systems/AdminVerbSystem.cs
+++ b/Content.Server/Administration/Systems/AdminVerbSystem.cs
@@ -388,6 +388,22 @@ namespace Content.Server.Administration.Systems
                         Icon = new SpriteSpecifier.Rsi(new ResPath("/Textures/Interface/Actions/actions_borg.rsi"), "state-laws"),
                     });
                 }
+
+                // open camera
+                args.Verbs.Add(new Verb()
+                {
+                    Priority = 10,
+                    Text = Loc.GetString("admin-verbs-camera"),
+                    Message = Loc.GetString("admin-verbs-camera-description"),
+                    Icon = new SpriteSpecifier.Texture(new("/Textures/Interface/VerbIcons/vv.svg.192dpi.png")),
+                    Category = VerbCategory.Admin,
+                    Act = () =>
+                    {
+                        var ui = new AdminCameraEui(args.Target);
+                        _euiManager.OpenEui(ui, player);
+                    },
+                    Impact = LogImpact.Low
+                });
             }
         }
 
diff --git a/Content.Server/Administration/UI/AdminCameraEui.cs b/Content.Server/Administration/UI/AdminCameraEui.cs
new file mode 100644
index 0000000000..5230933c82
--- /dev/null
+++ b/Content.Server/Administration/UI/AdminCameraEui.cs
@@ -0,0 +1,97 @@
+using Content.Server.Administration.Managers;
+using Content.Server.EUI;
+using Content.Shared.Administration;
+using Content.Shared.Eui;
+using Content.Shared.Follower;
+using Content.Shared.Coordinates;
+using Robust.Server.GameStates;
+using Robust.Shared.Player;
+using Robust.Shared.Prototypes;
+using Robust.Shared.Timing;
+using JetBrains.Annotations;
+
+namespace Content.Server.Administration.UI;
+
+/// <summary>
+/// Admin Eui for opening a viewport window to observe entities.
+/// Use the "Open Camera" admin verb or the "camera" command to open.
+/// </summary>
+[UsedImplicitly]
+public sealed partial class AdminCameraEui : BaseEui
+{
+    [Dependency] private readonly IAdminManager _admin = default!;
+    [Dependency] private readonly IEntityManager _entityManager = default!;
+    [Dependency] private readonly IGameTiming _timing = default!;
+
+    private readonly FollowerSystem _follower = default!;
+    private readonly PvsOverrideSystem _pvs = default!;
+    private readonly SharedViewSubscriberSystem _viewSubscriber = default!;
+
+    private static readonly EntProtoId CameraProtoId = "AdminCamera";
+
+    private readonly EntityUid _target;
+    private EntityUid? _camera;
+
+
+    public AdminCameraEui(EntityUid target)
+    {
+        IoCManager.InjectDependencies(this);
+        _follower = _entityManager.System<FollowerSystem>();
+        _pvs = _entityManager.System<PvsOverrideSystem>();
+        _viewSubscriber = _entityManager.System<SharedViewSubscriberSystem>();
+
+        _target = target;
+    }
+
+    public override void Opened()
+    {
+        base.Opened();
+
+        _camera = CreateCamera(_target, Player);
+        StateDirty();
+    }
+
+    public override void Closed()
+    {
+        base.Closed();
+
+        _entityManager.DeleteEntity(_camera);
+    }
+
+    public override void HandleMessage(EuiMessageBase msg)
+    {
+        base.HandleMessage(msg);
+
+        switch (msg)
+        {
+            case AdminCameraFollowMessage:
+                if (!_admin.HasAdminFlag(Player, AdminFlags.Admin) || Player.AttachedEntity == null)
+                    return;
+                _follower.StartFollowingEntity(Player.AttachedEntity.Value, _target);
+                break;
+            default:
+                break;
+        }
+    }
+
+    public override EuiStateBase GetNewState()
+    {
+        var name = _entityManager.GetComponent<MetaDataComponent>(_target).EntityName;
+        var netEnt = _entityManager.GetNetEntity(_camera);
+        return new AdminCameraEuiState(netEnt, name, _timing.CurTick);
+    }
+
+    private EntityUid CreateCamera(EntityUid target, ICommonSession observer)
+    {
+        // Spawn a camera entity attached to the target.
+        var coords = target.ToCoordinates();
+        var camera = _entityManager.SpawnAttachedTo(CameraProtoId, coords);
+
+        // Allow the user to see the entities near the camera.
+        // This also force sends the camera entity to the user, overriding the visibility flags.
+        // (The camera entity has its visibility flags set to VisibilityFlags.Admin so that cheat clients can't see it)
+        _viewSubscriber.AddViewSubscriber(camera, observer);
+
+        return camera;
+    }
+}
diff --git a/Content.Shared/Administration/AdminCameraEuiState.cs b/Content.Shared/Administration/AdminCameraEuiState.cs
new file mode 100644
index 0000000000..ae41f3aeb0
--- /dev/null
+++ b/Content.Shared/Administration/AdminCameraEuiState.cs
@@ -0,0 +1,27 @@
+using Content.Shared.Eui;
+using Robust.Shared.Serialization;
+using Robust.Shared.Timing;
+
+namespace Content.Shared.Administration;
+
+[Serializable, NetSerializable]
+public sealed partial class AdminCameraEuiState(NetEntity? camera, string name, GameTick tick) : EuiStateBase
+{
+    /// <summary>
+    /// The camera entity we will use for the window.
+    /// </summary>
+    public readonly NetEntity? Camera = camera;
+
+    /// <summary>
+    /// The name of the observed entity.
+    /// </summary>
+    public readonly string Name = name;
+
+    /// <summary>
+    /// The current tick time, needed for cursed reasons.
+    /// </summary>
+    public readonly GameTick Tick = tick;
+}
+
+[Serializable, NetSerializable]
+public sealed partial class AdminCameraFollowMessage : EuiMessageBase;
diff --git a/Content.Shared/Eye/VisibilityFlags.cs b/Content.Shared/Eye/VisibilityFlags.cs
index 432e80dd58..6cf8b18fca 100644
--- a/Content.Shared/Eye/VisibilityFlags.cs
+++ b/Content.Shared/Eye/VisibilityFlags.cs
@@ -6,9 +6,10 @@ namespace Content.Shared.Eye
     [FlagsFor(typeof(VisibilityMaskLayer))]
     public enum VisibilityFlags : int
     {
-        None   = 0,
+        None = 0,
         Normal = 1 << 0,
-        Ghost  = 1 << 1,
-        Subfloor = 1 << 2,
+        Ghost = 1 << 1, // Observers and revenants.
+        Subfloor = 1 << 2, // Pipes, disposal chutes, cables etc. while hidden under tiles. Can be revealed with a t-ray.
+        Admin = 1 << 3, // Reserved for admins in stealth mode and admin tools.
     }
 }
diff --git a/Content.Shared/Follower/FollowerSystem.cs b/Content.Shared/Follower/FollowerSystem.cs
index d8e34fb3ee..b9c2f4bece 100644
--- a/Content.Shared/Follower/FollowerSystem.cs
+++ b/Content.Shared/Follower/FollowerSystem.cs
@@ -189,6 +189,9 @@ public sealed class FollowerSystem : EntitySystem
     /// <param name="entity">The entity to be followed</param>
     public void StartFollowingEntity(EntityUid follower, EntityUid entity)
     {
+        if (follower == entity || TerminatingOrDeleted(entity))
+            return;
+
         // No recursion for you
         var targetXform = Transform(entity);
         while (targetXform.ParentUid.IsValid())
diff --git a/Resources/Locale/en-US/administration/admin-verbs.ftl b/Resources/Locale/en-US/administration/admin-verbs.ftl
index a89397bd65..13be0a876d 100644
--- a/Resources/Locale/en-US/administration/admin-verbs.ftl
+++ b/Resources/Locale/en-US/administration/admin-verbs.ftl
@@ -8,6 +8,8 @@ admin-verbs-teleport-here = Teleport Here
 admin-verbs-freeze = Freeze
 admin-verbs-freeze-and-mute = Freeze And Mute
 admin-verbs-unfreeze = Unfreeze
+admin-verbs-camera = Open Camera
+admin-verbs-camera-description = Open a camera window that follows the selected entity.
 admin-verbs-erase = Erase
 admin-verbs-erase-description = Removes the player from the round and crew manifest and deletes their chat messages.
     Their items are dropped on the ground.
diff --git a/Resources/Locale/en-US/administration/commands/camera.ftl b/Resources/Locale/en-US/administration/commands/camera.ftl
new file mode 100644
index 0000000000..98839683e0
--- /dev/null
+++ b/Resources/Locale/en-US/administration/commands/camera.ftl
@@ -0,0 +1,5 @@
+cmd-camera-desc = Opens a remote camera window for an entity.
+cmd-camera-help = Usage: camera <entityUid or player>
+
+cmd-camera-hint = <entityUid or player>
+cmd-camera-wrong-argument = Argument must be a valid netUid or a player name.
diff --git a/Resources/Locale/en-US/administration/ui/admin-camera-window.ftl b/Resources/Locale/en-US/administration/ui/admin-camera-window.ftl
new file mode 100644
index 0000000000..bf9f45a745
--- /dev/null
+++ b/Resources/Locale/en-US/administration/ui/admin-camera-window.ftl
@@ -0,0 +1,5 @@
+admin-camera-window-title = Observing { $name }
+admin-camera-window-title-placeholder = Observing
+admin-camera-window-follow = Follow
+admin-camera-window-pop-out = Pop out
+admin-camera-window-pop-in = Pop in
diff --git a/Resources/Locale/en-US/administration/ui/player-panel.ftl b/Resources/Locale/en-US/administration/ui/player-panel.ftl
index f2d89fe2c2..7b3571e380 100644
--- a/Resources/Locale/en-US/administration/ui/player-panel.ftl
+++ b/Resources/Locale/en-US/administration/ui/player-panel.ftl
@@ -22,3 +22,4 @@ player-panel-rejuvenate = Rejuvenate
 player-panel-false = False
 player-panel-true = True
 player-panel-follow = Follow
+player-panel-camera = Camera
diff --git a/Resources/Prototypes/Entities/Interface/admin_tools.yml b/Resources/Prototypes/Entities/Interface/admin_tools.yml
new file mode 100644
index 0000000000..a8c978ed0c
--- /dev/null
+++ b/Resources/Prototypes/Entities/Interface/admin_tools.yml
@@ -0,0 +1,14 @@
+# dummy entity for the admin camera EUI
+# this gets parented to the person being observed
+
+- type: entity
+  id: AdminCamera
+  categories: [ HideSpawnMenu ]
+  name: admin camera
+  description: We are watching you.
+  components:
+  - type: Visibility
+    layer: 8 # Don't network this to anyone so cheat clients can't see it. We are adding a PVS override to the user.
+  - type: Eye # for the camera itself
+    drawFov: false
+    pvsScale: 0.8 # we don't need the full range