From 7ec8b6e341c11b7b07ab0fb87405d79db68ede93 Mon Sep 17 00:00:00 2001
From: Haroon Qureshi <haroonq@google.com>
Date: Tue, 3 Feb 2026 06:48:51 -0800
Subject: [PATCH] Pause sim when loading an empty model.

PiperOrigin-RevId: 864855430
Change-Id: Ib8c2b0949ee6fda8dd1490017e146d792119e840
---
 src/experimental/studio/app.cc | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/experimental/studio/app.cc b/src/experimental/studio/app.cc
index 4eb5bbcc..350f8595 100644
--- a/src/experimental/studio/app.cc
+++ b/src/experimental/studio/app.cc
@@ -245,10 +245,16 @@ void App::LoadModelFromBuffer(std::span<const std::byte> buffer,
 
 void App::InitModel(mjModel* model, mjSpec* spec, mjVFS* vfs,
                     std::string filename, ModelKind model_kind) {
+  if (model_kind_ == kEmptyModel) {
+    step_control_.Unpause();
+  }
   ClearModel();
 
   model_path_ = std::move(filename);
   model_kind_ = model_kind;
+  if (model_kind_ == kEmptyModel) {
+    step_control_.Pause();
+  }
 
   spec_ = spec;
   model_ = model;