Damage masks (#9402)

Content.Shared/MobState/EntitySystems/SharedMobStateSystem.Dead.cs

@@ -0,0 +1,36 @@
+using Content.Shared.FixedPoint;
+
+namespace Content.Shared.MobState.EntitySystems;
+
+public abstract partial class SharedMobStateSystem
+{
+    public virtual void EnterDeadState(EntityUid uid)
+    {
+        EnsureComp<CollisionWakeComponent>(uid);
+        Standing.Down(uid);
+
+        if (Standing.IsDown(uid) && TryComp<PhysicsComponent>(uid, out var physics))
+        {
+            physics.CanCollide = false;
+        }
+
+        if (TryComp<AppearanceComponent>(uid, out var appearance))
+        {
+            appearance.SetData(DamageStateVisuals.State, DamageState.Dead);
+        }
+    }
+
+    public virtual void ExitDeadState(EntityUid uid)
+    {
+        RemComp<CollisionWakeComponent>(uid);
+
+        Standing.Stand(uid);
+
+        if (!Standing.IsDown(uid) && TryComp<PhysicsComponent>(uid, out var physics))
+        {
+            physics.CanCollide = true;
+        }
+    }
+
+    public virtual void UpdateDeadState(EntityUid entity, FixedPoint2 threshold) {}
+}