Refactor thrusters (#15698)

Content.Server/Shuttles/Systems/ThrusterSystem.cs

@@ -13,6 +13,7 @@ using Content.Shared.Shuttles.Components;
 using Content.Shared.Temperature;
 using Robust.Server.GameObjects;
 using Robust.Shared.Map;
+using Robust.Shared.Map.Components;
 using Robust.Shared.Physics.Collision.Shapes;
 using Robust.Shared.Physics.Components;
 using Robust.Shared.Physics.Events;
@@ -295,6 +296,38 @@ public sealed class ThrusterSystem : EntitySystem
         }
 
         _ambient.SetAmbience(uid, true);
+        RefreshCenter(uid, shuttleComponent);
+    }
+
+    /// <summary>
+    /// Refreshes the center of thrust for movement calculations.
+    /// </summary>
+    private void RefreshCenter(EntityUid uid, ShuttleComponent shuttle)
+    {
+        // TODO: Only refresh relevant directions.
+        var center = Vector2.Zero;
+        var thrustQuery = GetEntityQuery<ThrusterComponent>();
+        var xformQuery = GetEntityQuery<TransformComponent>();
+
+        foreach (var dir in new[]
+                     { Direction.South, Direction.East, Direction.North, Direction.West })
+        {
+            var index = (int) dir / 2;
+            var pop = shuttle.LinearThrusters[index];
+            var totalThrust = 0f;
+
+            foreach (var ent in pop)
+            {
+                if (!thrustQuery.TryGetComponent(ent, out var thruster) || !xformQuery.TryGetComponent(ent, out var xform))
+                    continue;
+
+                center += xform.LocalPosition * thruster.Thrust;
+                totalThrust += thruster.Thrust;
+            }
+
+            center /= pop.Count * totalThrust;
+            shuttle.CenterOfThrust[index] = center;
+        }
     }
 
     public void DisableThruster(EntityUid uid, ThrusterComponent component, TransformComponent? xform = null, Angle? angle = null)
@@ -358,6 +391,7 @@ public sealed class ThrusterSystem : EntitySystem
         }
 
         component.Colliding.Clear();
+        RefreshCenter(uid, shuttleComponent);
     }
 
     public bool CanEnable(EntityUid uid, ThrusterComponent component)