From a287a7979dfb35475f5fad6e92df674cd54a5c16 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=CE=B6eh=20Matt?= <5415177+ZehMatt@users.noreply.github.com>
Date: Fri, 21 Mar 2025 01:21:00 +0200
Subject: [PATCH] Improve performance of spatial indexing

---
 src/openrct2/entity/EntityRegistry.cpp | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/src/openrct2/entity/EntityRegistry.cpp b/src/openrct2/entity/EntityRegistry.cpp
index 76c83ba2f8..94afb04316 100644
--- a/src/openrct2/entity/EntityRegistry.cpp
+++ b/src/openrct2/entity/EntityRegistry.cpp
@@ -452,7 +452,7 @@ void UpdateEntitiesSpatialIndex()
     {
         for (auto& entityId : entityList)
         {
-            auto* entity = GetEntity(entityId);
+            auto* entity = TryGetEntity(entityId);
             if (entity == nullptr || entity->Type == EntityType::Null)
                 continue;
 
@@ -475,9 +475,29 @@ CoordsXYZ EntityBase::GetLocation() const
 
 void EntityBase::SetLocation(const CoordsXYZ& newLocation)
 {
+    if (GetLocation() == newLocation)
+    {
+        // No change, this can happen quite often when the entity is interpolated.
+        return;
+    }
+
     x = newLocation.x;
     y = newLocation.y;
     z = newLocation.z;
+
+    if (SpatialIndex & kSpatialIndexDirtyMask)
+    {
+        // Already marked as dirty.
+        return;
+    }
+
+    const auto newSpatialIndex = ComputeSpatialIndex({ x, y });
+    if (newSpatialIndex == GetSpatialIndex(this))
+    {
+        // Avoid marking it dirty when we don't leave the current tile.
+        return;
+    }
+
     SpatialIndex |= kSpatialIndexDirtyMask;
 }