diff --git a/tetris/functions.cpp b/tetris/functions.cpp
index 274a7fe..3b55a46 100644
--- a/tetris/functions.cpp
+++ b/tetris/functions.cpp
@@ -118,6 +118,8 @@ void quitGame() {
 }
 
 void resetGame() {
+    std::lock_guard< std::mutex > guard( g_render_mutex );
+    std::lock_guard< std::mutex > guard2( g_movement_mutex );
     g_cur_object.reset();
     g_checked_line = true;
     g_next_object.reset();
diff --git a/tetris/global_vars.cpp b/tetris/global_vars.cpp
index d92065a..2e79c21 100644
--- a/tetris/global_vars.cpp
+++ b/tetris/global_vars.cpp
@@ -36,6 +36,7 @@ std::shared_ptr< TetrisPiece > g_cur_shadow{};
 std::shared_ptr< SDLPP::RectangleRender > g_shadow_colider{};
 
 std::mutex g_movement_mutex{};
+std::mutex g_render_mutex{};
 
 bool g_quit = false;
 std::vector< std::function< void(
diff --git a/tetris/global_vars.hpp b/tetris/global_vars.hpp
index 7b3af25..8568584 100644
--- a/tetris/global_vars.hpp
+++ b/tetris/global_vars.hpp
@@ -42,6 +42,7 @@ extern std::shared_ptr< TetrisPiece > g_cur_shadow;
 extern std::shared_ptr< SDLPP::RectangleRender > g_shadow_colider;
 
 extern std::mutex g_movement_mutex;
+extern std::mutex g_render_mutex;
 
 extern bool g_quit;
 extern std::vector< std::function< void(
diff --git a/tetris/tetris.cpp b/tetris/tetris.cpp
index 8222d53..a875a93 100644
--- a/tetris/tetris.cpp
+++ b/tetris/tetris.cpp
@@ -157,12 +157,15 @@ int main() {
             g_update_objects.pop_back();
         }
 
-        renderer->clearRenderer();
-        for ( size_t i = 0; i < g_active_scenes.size(); i++ ) {
-            g_active_scenes[i]->updateScene();
-            g_active_scenes[i]->renderScene( false );
+        {
+            std::lock_guard< std::mutex > guard( g_render_mutex );
+            renderer->clearRenderer();
+            for ( size_t i = 0; i < g_active_scenes.size(); i++ ) {
+                g_active_scenes[i]->updateScene();
+                g_active_scenes[i]->renderScene( false );
+            }
+            renderer->presentRenderer();
         }
-        renderer->presentRenderer();
         g_wait_for_anim = false;
         frames++;
         if ( SDL_GetTicks() - base >= 1000 ) {