From 7ee49d8f2b5c8f88c1c0a16c6e2f8575c893f364 Mon Sep 17 00:00:00 2001
From: mix <mixiate@proton.me>
Date: Sun, 25 May 2025 21:37:58 +0100
Subject: [PATCH] Fix #23289: Dodgems and Flying Saucers can spawn on top of
 each other

---
 distribution/changelog.txt             |  1 +
 src/openrct2/entity/EntityBase.h       |  2 ++
 src/openrct2/entity/EntityRegistry.cpp | 29 ++++++++++++++++++--------
 src/openrct2/ride/Ride.cpp             |  2 +-
 4 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/distribution/changelog.txt b/distribution/changelog.txt
index 2cad08f413..bcfbf5c697 100644
--- a/distribution/changelog.txt
+++ b/distribution/changelog.txt
@@ -18,6 +18,7 @@
 - Fix: [#5269] Font bugs when using the Russian release of RCT2 as the base game.
 - Fix: [#11071, #22958] The virtual floor does not always draw correctly.
 - Fix: [#20158] Custom animated scenery .DATs with frame offsets draw a random sprite at the end of their animation.
+- Fix: [#23289] Dodgems and Flying Saucer cars can spawn on top of each other when the ride is opened.
 - Fix: [#24332] Banner font renders differently when using RCT Classic as the base game.
 - Fix: [#24346] Possible crash during line drawing in OpenGL mode.
 - Fix: [#24353] ‘Show dirty visuals’ is off by one pixel and does not work correctly with higher framerates.
diff --git a/src/openrct2/entity/EntityBase.h b/src/openrct2/entity/EntityBase.h
index 77b887aff2..56918a6006 100644
--- a/src/openrct2/entity/EntityBase.h
+++ b/src/openrct2/entity/EntityBase.h
@@ -54,6 +54,8 @@ struct EntityBase
      */
     void MoveTo(const CoordsXYZ& newLocation);
 
+    void MoveToAndUpdateSpatialIndex(const CoordsXYZ& newLocation);
+
     /**
      * Sets the entity location without screen invalidation.
      */
diff --git a/src/openrct2/entity/EntityRegistry.cpp b/src/openrct2/entity/EntityRegistry.cpp
index c9e8802052..89474dc7e3 100644
--- a/src/openrct2/entity/EntityRegistry.cpp
+++ b/src/openrct2/entity/EntityRegistry.cpp
@@ -448,6 +448,18 @@ static void EntitySpatialRemove(EntityBase& entity)
     entity.SpatialIndex = kInvalidSpatialIndex;
 }
 
+static void UpdateEntitySpatialIndex(EntityBase& entity)
+{
+    if (entity.SpatialIndex & kSpatialIndexDirtyMask)
+    {
+        if (entity.SpatialIndex != kInvalidSpatialIndex)
+        {
+            EntitySpatialRemove(entity);
+        }
+        EntitySpatialInsert(entity, { entity.x, entity.y });
+    }
+}
+
 void UpdateEntitiesSpatialIndex()
 {
     for (auto& entityList : gEntityLists)
@@ -455,16 +467,9 @@ void UpdateEntitiesSpatialIndex()
         for (auto& entityId : entityList)
         {
             auto* entity = TryGetEntity(entityId);
-            if (entity == nullptr || entity->Type == EntityType::Null)
-                continue;
-
-            if (entity->SpatialIndex & kSpatialIndexDirtyMask)
+            if (entity != nullptr && entity->Type != EntityType::Null)
             {
-                if (entity->SpatialIndex != kInvalidSpatialIndex)
-                {
-                    EntitySpatialRemove(*entity);
-                }
-                EntitySpatialInsert(*entity, { entity->x, entity->y });
+                UpdateEntitySpatialIndex(*entity);
             }
         }
     }
@@ -538,6 +543,12 @@ void EntityBase::MoveTo(const CoordsXYZ& newLocation)
     }
 }
 
+void EntityBase::MoveToAndUpdateSpatialIndex(const CoordsXYZ& newLocation)
+{
+    MoveTo(newLocation);
+    UpdateEntitySpatialIndex(*this);
+}
+
 /**
  * Frees any dynamically attached memory to the entity, such as peep name.
  */
diff --git a/src/openrct2/ride/Ride.cpp b/src/openrct2/ride/Ride.cpp
index 1f96f2a96d..0e6a4f49f1 100644
--- a/src/openrct2/ride/Ride.cpp
+++ b/src/openrct2/ride/Ride.cpp
@@ -3308,7 +3308,7 @@ static Vehicle* VehicleCreateCar(
             chosenLoc.x = dodgemPos.x + (ScenarioRand() & 0xFF);
         } while (vehicle->DodgemsCarWouldCollideAt(chosenLoc).has_value());
 
-        vehicle->MoveTo({ chosenLoc, dodgemPos.z });
+        vehicle->MoveToAndUpdateSpatialIndex({ chosenLoc, dodgemPos.z });
     }
     else
     {