move the ui/shaders reload into the ui thread, add rtt region copy, add box/rect conversion

src/app.cpp

@@ -577,7 +577,6 @@ void App::draw(float dt)
 void App::update(float dt)
 {
     static std::mutex mutex;
-    static float reload_timer = 0.f;
 
     // avoid multiple threads to update the scene
     //std::lock_guard<std::mutex> lock(mutex);
@@ -585,17 +584,6 @@ void App::update(float dt)
     if (!(redraw || animate))
         return;
 
-#if /*_DEBUG &&*/ (_WIN32 || __OSX__)
-    reload_timer += dt;
-    if (reload_timer > 1.0)
-    {
-        reload_timer = 0;
-        if (ShaderManager::reload())
-            stroke->update_controls();
-        layout.reload();
-    }
-#endif
-
     if (auto* main = layout[main_id])
         main->update(width, height, zoom);
 
@@ -843,6 +831,7 @@ void App::ui_thread_main()
     auto t_start = std::chrono::high_resolution_clock::now();
     float t_frame = 0;
     float t_fps_counter = 0;
+    float t_reloader = 0;
     int rendered_frames = 0;
     while (ui_running)
     {
@@ -891,6 +880,23 @@ void App::ui_thread_main()
             rendered_frames = 0;
         }
 
+#if /*_DEBUG &&*/ (_WIN32 || __OSX__)
+        t_reloader += dt;
+        if (t_reloader > 1.0)
+        {
+            t_reloader = 0;
+            if (ShaderManager::reload())
+            {
+                stroke->update_controls();
+                redraw = true;
+            }
+            if (layout.reload())
+            {
+                redraw = true;
+            }
+        }
+#endif
+
         tick(dt);
 
         if (redraw)