From f183d901cbeadcd1cf021c4edd66fe8d7e68535e Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Mon, 13 May 2019 13:31:36 +0200
Subject: [PATCH] bullet: sync rigid body transform when node is reparented

Reparenting a node will change its net transform, so it should cause a transform sync.

Fixes #629
---
 panda/src/bullet/bulletRigidBodyNode.cxx | 14 ++++++++++++++
 panda/src/bullet/bulletRigidBodyNode.h   |  1 +
 2 files changed, 15 insertions(+)

diff --git a/panda/src/bullet/bulletRigidBodyNode.cxx b/panda/src/bullet/bulletRigidBodyNode.cxx
index b97f768d1b..acd7e96e79 100644
--- a/panda/src/bullet/bulletRigidBodyNode.cxx
+++ b/panda/src/bullet/bulletRigidBodyNode.cxx
@@ -359,6 +359,20 @@ do_transform_changed() {
   }
 }
 
+/**
+ *
+ */
+void BulletRigidBodyNode::
+parents_changed() {
+
+  if (_motion.sync_disabled()) return;
+
+  if (get_num_parents() > 0) {
+    LightMutexHolder holder(BulletWorld::get_global_lock());
+    do_transform_changed();
+  }
+}
+
 /**
  *
  */
diff --git a/panda/src/bullet/bulletRigidBodyNode.h b/panda/src/bullet/bulletRigidBodyNode.h
index d0e11da6cf..246dec3e6c 100644
--- a/panda/src/bullet/bulletRigidBodyNode.h
+++ b/panda/src/bullet/bulletRigidBodyNode.h
@@ -112,6 +112,7 @@ public:
   void do_sync_b2p();
 
 protected:
+  virtual void parents_changed();
   virtual void transform_changed();
 
 private: