fix bluespace shelter capsules (#3674)

Co-authored-by: deltanedas <@deltanedas:kde.org>

Content.Server/_DV/Salvage/Systems/ShelterCapsuleSystem.cs

@@ -9,6 +9,7 @@ using Content.Shared.Maps;
 using Content.Shared.Physics;
 using Robust.Shared.Map.Components;
 using Robust.Shared.Maths;
+using Robust.Shared.Physics;
 using Robust.Shared.Prototypes;
 using System.Numerics;
 
@@ -22,11 +23,18 @@ public sealed class ShelterCapsuleSystem : SharedShelterCapsuleSystem
     [Dependency] private readonly ISharedAdminLogManager _adminLogger = default!;
     [Dependency] private readonly SharedMapSystem _map = default!;
     [Dependency] private readonly SmokeSystem _smoke = default!;
-    [Dependency] private readonly TurfSystem _turf = default!;
 
-    public EntProtoId SmokePrototype = "Smoke";
+    public static readonly EntProtoId SmokePrototype = "Smoke";
 
-    private HashSet<Entity<TransformComponent>> _entities = new();
+    private EntityQuery<FixturesComponent> _fixturesQuery;
+    private HashSet<EntityUid> _entities = new();
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        _fixturesQuery = GetEntityQuery<FixturesComponent>();
+    }
 
     protected override LocId? TrySpawnRoom(Entity<ShelterCapsuleComponent> ent)
     {
@@ -34,13 +42,16 @@ public sealed class ShelterCapsuleSystem : SharedShelterCapsuleSystem
         if (xform.GridUid is not {} gridUid || !TryComp<MapGridComponent>(gridUid, out var grid))
             return "shelter-capsule-error-space";
 
-        var gridXform = Transform(gridUid);
         var center = _map.LocalToTile(gridUid, grid, xform.Coordinates);
         var room = _proto.Index(ent.Comp.Room);
         var origin = center - room.Size / 2;
 
         // check that every tile it needs isn't blocked
-        var mask = CollisionGroup.MobMask;
+        var mask = (int) CollisionGroup.MobMask;
+        if (IsAreaBlocked(gridUid, center, room.Size, mask))
+            return "shelter-capsule-error-obstructed";
+
+        // check that it isn't on space or SpawnRoom will crash
         for (int y = 0; y < room.Size.Y; y++)
         {
             for (int x = 0; x < room.Size.X; x++)
@@ -49,9 +60,6 @@ public sealed class ShelterCapsuleSystem : SharedShelterCapsuleSystem
                 var tile = _map.GetTileRef((gridUid, grid), pos);
                 if (tile.Tile.IsEmpty)
                     return "shelter-capsule-error-space";
-
-                if (_turf.IsTileBlocked(gridUid, pos, mask, grid, gridXform))
-                    return "shelter-capsule-error-obstructed";
             }
         }
 
@@ -73,4 +81,29 @@ public sealed class ShelterCapsuleSystem : SharedShelterCapsuleSystem
         QueueDel(ent);
         return null;
     }
+
+    private bool IsAreaBlocked(EntityUid grid, Vector2i center, Vector2i size, int mask)
+    {
+        // This is scaled to 95 % so it doesn't encompass walls on other tiles.
+        var aabb = Box2.CenteredAround(center, size * 0.95f);
+        _entities.Clear();
+        _lookup.GetLocalEntitiesIntersecting(grid, aabb, _entities, LookupFlags.Dynamic | LookupFlags.Static);
+        foreach (var uid in _entities)
+        {
+            // don't care about non-physical entities
+            if (!_fixturesQuery.TryComp(uid, out var fixtures))
+                continue;
+
+            foreach (var fixture in fixtures.Fixtures.Values)
+            {
+                if (!fixture.Hard)
+                    continue;
+
+                if ((fixture.CollisionLayer & mask) != 0)
+                    return true;
+            }
+        }
+
+        return false; // no entities colliding with the mask found
+    }
 }