From 55565ea22a40b5d0613a99f2d4529da79baac249 Mon Sep 17 00:00:00 2001
From: Leon Friedrich <60421075+ElectroJr@users.noreply.github.com>
Date: Sun, 29 May 2022 11:31:43 +1200
Subject: [PATCH] step trigger fix + optimization (#8503)

---
 .../StepTrigger/StepTriggerComponent.cs       | 12 +++--
 .../StepTrigger/StepTriggerSystem.cs          | 46 +++++++++----------
 2 files changed, 32 insertions(+), 26 deletions(-)

diff --git a/Content.Shared/StepTrigger/StepTriggerComponent.cs b/Content.Shared/StepTrigger/StepTriggerComponent.cs
index c54e77e786..76f16b48a7 100644
--- a/Content.Shared/StepTrigger/StepTriggerComponent.cs
+++ b/Content.Shared/StepTrigger/StepTriggerComponent.cs
@@ -1,4 +1,4 @@
-using Robust.Shared.GameStates;
+using Robust.Shared.GameStates;
 using Robust.Shared.Serialization;
 
 namespace Content.Shared.StepTrigger;
@@ -11,12 +11,14 @@ public sealed class StepTriggerComponent : Component
     /// <summary>
     ///     List of entities that are currently colliding with the entity.
     /// </summary>
+    [ViewVariables]
     public readonly HashSet<EntityUid> Colliding = new();
 
     /// <summary>
     ///     The list of entities that are standing on this entity,
     /// which shouldn't be able to trigger it again until stepping off.
     /// </summary>
+    [ViewVariables]
     public readonly HashSet<EntityUid> CurrentlySteppedOn = new();
 
     /// <summary>
@@ -50,13 +52,17 @@ public sealed class StepTriggerComponentState : ComponentState
 {
     public float IntersectRatio { get; }
     public float RequiredTriggerSpeed { get; }
-    public readonly EntityUid[] CurrentlySteppedOn;
+    public readonly HashSet<EntityUid> CurrentlySteppedOn;
+    public readonly HashSet<EntityUid> Colliding;
+    public readonly bool Active;
 
-    public StepTriggerComponentState(float intersectRatio, EntityUid[] currentlySteppedOn, float requiredTriggerSpeed)
+    public StepTriggerComponentState(float intersectRatio, HashSet<EntityUid> currentlySteppedOn, HashSet<EntityUid> colliding, float requiredTriggerSpeed, bool active)
     {
         IntersectRatio = intersectRatio;
         CurrentlySteppedOn = currentlySteppedOn;
         RequiredTriggerSpeed = requiredTriggerSpeed;
+        Active = active;
+        Colliding = colliding;
     }
 }
 
diff --git a/Content.Shared/StepTrigger/StepTriggerSystem.cs b/Content.Shared/StepTrigger/StepTriggerSystem.cs
index 2c242f0a58..33b18585bc 100644
--- a/Content.Shared/StepTrigger/StepTriggerSystem.cs
+++ b/Content.Shared/StepTrigger/StepTriggerSystem.cs
@@ -1,4 +1,4 @@
-using System.Linq;
+using System.Linq;
 using Robust.Shared.GameStates;
 using Robust.Shared.Physics.Dynamics;
 
@@ -18,25 +18,25 @@ public sealed class StepTriggerSystem : EntitySystem
 
     public override void Update(float frameTime)
     {
-        foreach (var (_, trigger, transform) in EntityQuery<StepTriggerActiveComponent, StepTriggerComponent, TransformComponent>())
+        var query = GetEntityQuery<PhysicsComponent>();
+        foreach (var (active, trigger, transform) in EntityQuery<StepTriggerActiveComponent, StepTriggerComponent, TransformComponent>())
         {
-            if (!Update(trigger, transform))
+            if (!Update(trigger, transform, query))
                 continue;
 
-            RemComp<StepTriggerActiveComponent>(trigger.Owner);
+            RemComp(trigger.Owner, active);
         }
     }
 
-    private bool Update(StepTriggerComponent component, TransformComponent transform)
+    private bool Update(StepTriggerComponent component, TransformComponent transform, EntityQuery<PhysicsComponent> query)
     {
         if (!component.Active ||
             component.Colliding.Count == 0)
             return true;
 
-
         foreach (var otherUid in component.Colliding.ToArray())
         {
-            var shouldRemoveFromColliding = UpdateColliding(component, transform, otherUid);
+            var shouldRemoveFromColliding = UpdateColliding(component, transform, otherUid, query);
             if (!shouldRemoveFromColliding) continue;
 
             component.Colliding.Remove(otherUid);
@@ -46,16 +46,11 @@ public sealed class StepTriggerSystem : EntitySystem
         return false;
     }
 
-    private bool UpdateColliding(StepTriggerComponent component, TransformComponent ownerTransform, EntityUid otherUid)
+    private bool UpdateColliding(StepTriggerComponent component, TransformComponent ownerTransform, EntityUid otherUid, EntityQuery<PhysicsComponent> query)
     {
-        if (!TryComp(otherUid, out PhysicsComponent? otherPhysics))
+        if (!query.TryGetComponent(otherUid, out var otherPhysics))
             return true;
 
-        if (component.CurrentlySteppedOn.Contains(otherUid) ||
-            !CanTrigger(component.Owner, otherUid, component) ||
-            otherPhysics.LinearVelocity.Length < component.RequiredTriggerSpeed)
-            return false;
-
         // TODO: This shouldn't be calculating based on world AABBs.
         var ourAabb = _entityLookup.GetWorldAABB(component.Owner, ownerTransform);
         var otherAabb = _entityLookup.GetWorldAABB(otherUid);
@@ -63,8 +58,10 @@ public sealed class StepTriggerSystem : EntitySystem
         if (!ourAabb.Intersects(otherAabb))
             return true;
 
-        var percentage = otherAabb.IntersectPercentage(ourAabb);
-        if (percentage < component.IntersectRatio)
+        if (otherPhysics.LinearVelocity.Length < component.RequiredTriggerSpeed
+            || component.CurrentlySteppedOn.Contains(otherUid)
+            || otherAabb.IntersectPercentage(ourAabb) < component.IntersectRatio
+            || !CanTrigger(component.Owner, otherUid, component))
             return false;
 
         var ev = new StepTriggeredEvent { Source = component.Owner, Tripper = otherUid };
@@ -106,20 +103,23 @@ public sealed class StepTriggerSystem : EntitySystem
 
         component.RequiredTriggerSpeed = state.RequiredTriggerSpeed;
         component.IntersectRatio = state.IntersectRatio;
-        component.CurrentlySteppedOn.Clear();
+        component.Active = state.Active;
 
-        foreach (var slipped in state.CurrentlySteppedOn)
-        {
-            component.CurrentlySteppedOn.Add(slipped);
-        }
+        component.CurrentlySteppedOn.Clear();
+        component.Colliding.Clear();
+
+        component.CurrentlySteppedOn.UnionWith(state.CurrentlySteppedOn);
+        component.Colliding.UnionWith(state.Colliding);
     }
 
     private static void TriggerGetState(EntityUid uid, StepTriggerComponent component, ref ComponentGetState args)
     {
         args.State = new StepTriggerComponentState(
             component.IntersectRatio,
-            component.CurrentlySteppedOn.ToArray(),
-            component.RequiredTriggerSpeed);
+            component.CurrentlySteppedOn,
+            component.Colliding,
+            component.RequiredTriggerSpeed,
+            component.Active);
     }
 
     public void SetIntersectRatio(EntityUid uid, float ratio, StepTriggerComponent? component = null)