From 01b0ea5b7ddc712d7c0649d4c06f5ba12a8585f7 Mon Sep 17 00:00:00 2001
From: Haroon Qureshi <haroonq@google.com>
Date: Wed, 5 Nov 2025 09:16:44 -0800
Subject: [PATCH] Use webgl backend in emscripten builds.

(Also only display the model name if its a file.)

PiperOrigin-RevId: 828498906
Change-Id: I7def85992f413b321c115ea63db2af057f5fd372
---
 src/experimental/studio/app.cc | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/experimental/studio/app.cc b/src/experimental/studio/app.cc
index 93f818ae..f8cad0f4 100644
--- a/src/experimental/studio/app.cc
+++ b/src/experimental/studio/app.cc
@@ -57,7 +57,9 @@ namespace mujoco::studio {
 // - async physics
 
 static constexpr toolbox::Window::Config kWindowConfig = {
-#if defined(USE_FILAMENT_VULKAN)
+#ifdef EMSCRIPTEN
+    .render_config = toolbox::Window::RenderConfig::kFilamentWebGL,
+#elif defined(USE_FILAMENT_VULKAN)
     .render_config = toolbox::Window::RenderConfig::kFilamentVulkan,
 #elif defined(USE_FILAMENT_OPENGL)
     .render_config = toolbox::Window::RenderConfig::kFilamentOpenGL,
@@ -163,10 +165,11 @@ void App::OnModelLoaded(std::string_view model_file) {
   tmp_ = UiTempState();
   mjv_defaultOption(&vis_options_);
   ClearProfilerData();
-  if (model_file.empty()) {
-    window_->SetTitle("MuJoCo Studio");
-  } else {
+  if (!model_file.empty() &&
+      (model_file.ends_with(".xml") || model_file.ends_with(".mjb"))) {
     window_->SetTitle("MuJoCo Studio : " + std::string(model_file));
+  } else {
+    window_->SetTitle("MuJoCo Studio");
   }
 }