Indicator fixes (#357)

* - fix: Fix hud showing stealth entities.

* - fix: Fix aghost SSD indicator.

* - tweak: Make ninja more stealthy.

Content.Client/StatusIcon/StatusIconSystem.cs

@@ -1,7 +1,10 @@
 using Content.Shared.CCVar;
+using Content.Shared.Ghost;
 using Content.Shared.StatusIcon;
 using Content.Shared.StatusIcon.Components;
+using Robust.Client.GameObjects;
 using Robust.Client.Graphics;
+using Robust.Client.Player;
 using Robust.Shared.Configuration;
 
 namespace Content.Client.StatusIcon;
@@ -13,6 +16,10 @@ public sealed class StatusIconSystem : SharedStatusIconSystem
 {
     [Dependency] private readonly IConfigurationManager _configuration = default!;
     [Dependency] private readonly IOverlayManager _overlay = default!;
+    [Dependency] private readonly IPlayerManager _playerMan = default!;
+
+    private EntityQuery<GhostComponent> _ghostQuery;
+    private EntityQuery<SpriteComponent> _spriteQuery;
 
     private bool _globalEnabled;
     private bool _localEnabled;
@@ -20,6 +27,9 @@ public sealed class StatusIconSystem : SharedStatusIconSystem
     /// <inheritdoc/>
     public override void Initialize()
     {
+        _ghostQuery = GetEntityQuery<GhostComponent>();
+        _spriteQuery = GetEntityQuery<SpriteComponent>();
+
         Subs.CVar(_configuration, CCVars.LocalStatusIconsEnabled, OnLocalStatusIconChanged, true);
         Subs.CVar(_configuration, CCVars.GlobalStatusIconsEnabled, OnGlobalStatusIconChanged, true);
     }
@@ -59,5 +69,29 @@ public sealed class StatusIconSystem : SharedStatusIconSystem
         RaiseLocalEvent(uid, ref ev);
         return ev.StatusIcons;
     }
+
+    /// <summary>
+    /// For overlay to check if an entity can be seen.
+    /// </summary>
+    public bool IsVisible(EntityUid uid)
+    {
+        // ghosties can always see them
+        var viewer = _playerMan.LocalSession?.AttachedEntity;
+        if (_ghostQuery.HasComponent(viewer))
+            return true;
+
+        if (_spriteQuery.TryGetComponent(uid, out var sprite) && !sprite.Visible)
+            return false;
+
+        var ev = new StatusIconVisibleEvent(true);
+        RaiseLocalEvent(uid, ref ev);
+        return ev.Visible;
+    }
 }
 
+/// <summary>
+/// Raised on an entity to check if it should draw hud icons.
+/// Used to check invisibility etc inside the screen bounds.
+/// </summary>
+[ByRefEvent]
+public record struct StatusIconVisibleEvent(bool Visible);