From 11cb074f9576bbd31bedd0ec6890428e0c5a2f02 Mon Sep 17 00:00:00 2001
From: MarieENSG <marie.moulard88@gmail.com>
Date: Wed, 3 Jun 2026 10:23:34 +0200
Subject: [PATCH] feat(MedialBallsExtractor): mutex in ray tracing

---
 src/geode/model/helpers/ray_tracing.cpp | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/geode/model/helpers/ray_tracing.cpp b/src/geode/model/helpers/ray_tracing.cpp
index 4aabbd998..7076e9a0e 100644
--- a/src/geode/model/helpers/ray_tracing.cpp
+++ b/src/geode/model/helpers/ray_tracing.cpp
@@ -23,6 +23,8 @@
 
 #include <geode/model/helpers/ray_tracing.hpp>
 
+#include <absl/synchronization/mutex.h>
+
 #include <geode/basic/pimpl_impl.hpp>
 
 #include <geode/geometry/aabb.hpp>
@@ -298,10 +300,14 @@ namespace geode
     private:
         const AABBTree3D& surface_aabb( const Surface3D& surface )
         {
-            if( aabb_trees_.contains( surface.id() ) )
             {
-                return aabb_trees_.at( surface.id() );
+                absl::ReaderMutexLock read_lock{ mutex_ };
+                if( aabb_trees_.contains( surface.id() ) )
+                {
+                    return aabb_trees_.at( surface.id() );
+                }
             }
+            absl::MutexLock lock{ mutex_ };
             return aabb_trees_
                 .emplace( surface.id(), create_aabb_tree( surface.mesh() ) )
                 .first->second;
@@ -310,6 +316,7 @@ namespace geode
     private:
         const BRep& brep_;
         absl::flat_hash_map< uuid, AABBTree3D > aabb_trees_;
+        absl::Mutex mutex_;
     };
 
     BRepRayTracing::BRepRayTracing( const BRep& brep ) : impl_{ brep } {}