From ec8d53888677502e3052b27d603bc8d6fce21311 Mon Sep 17 00:00:00 2001
From: Erin Catto <erincatto@users.noreply.github.com>
Date: Sat, 5 Oct 2024 23:01:34 -0700
Subject: [PATCH] tried rebuilding static tree

---
 include/box2d/box2d.h |  3 +++
 src/dynamic_tree.c    |  9 +++------
 src/world.c           | 14 ++++++++++++++
 3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/include/box2d/box2d.h b/include/box2d/box2d.h
index af3eec88a..2d2b688c2 100644
--- a/include/box2d/box2d.h
+++ b/include/box2d/box2d.h
@@ -184,6 +184,9 @@ B2_API b2Counters b2World_GetCounters( b2WorldId worldId );
 /// Dump memory stats to box2d_memory.txt
 B2_API void b2World_DumpMemoryStats( b2WorldId worldId );
 
+/// todo testing
+B2_API void b2World_RebuildStaticTree( b2WorldId worldId );
+
 /** @} */
 
 /**
diff --git a/src/dynamic_tree.c b/src/dynamic_tree.c
index 28bf972a6..7f188aec8 100644
--- a/src/dynamic_tree.c
+++ b/src/dynamic_tree.c
@@ -1477,7 +1477,6 @@ static int32_t b2PartitionMid( int32_t* indices, b2Vec2* centers, int32_t count
 		return count / 2;
 	}
 
-	// todo SIMD?
 	b2Vec2 lowerBound = centers[0];
 	b2Vec2 upperBound = centers[0];
 
@@ -1574,15 +1573,13 @@ static int32_t b2PartitionMid( int32_t* indices, b2Vec2* centers, int32_t count
 	{
 		return i1;
 	}
-	else
-	{
-		return count / 2;
-	}
+
+	return count / 2;
 }
 
 #else
 
-#define B2_BIN_COUNT 8
+#define B2_BIN_COUNT 64
 
 typedef struct b2TreeBin
 {
diff --git a/src/world.c b/src/world.c
index 1a89e193f..a6426ecc1 100644
--- a/src/world.c
+++ b/src/world.c
@@ -2524,6 +2524,20 @@ void b2World_Explode( b2WorldId worldId, const b2ExplosionDef* explosionDef )
 						 &explosionContext );
 }
 
+void b2World_RebuildStaticTree(b2WorldId worldId)
+{
+	b2World* world = b2GetWorldFromId( worldId );
+	B2_ASSERT( world->locked == false );
+	if ( world->locked )
+	{
+		return;
+	}
+
+	b2DynamicTree* staticTree = world->broadPhase.trees + b2_staticBody;
+	b2DynamicTree_Rebuild( staticTree, true );
+}
+
+
 #if B2_VALIDATE
 // When validating islands ids I have to compare the root island
 // ids because islands are not merged until the next time step.