minor refactor

src/engine.cpp

@@ -155,26 +155,32 @@ void Engine::mainloop() {
         screen->update(delta);
 
         if (!Window::isIconified()) {
+            renderFrame(batch);
+        }
+        Window::swapInterval(Window::isIconified() ? 1 : settings.display.swapInterval);
+
+        processPostRunnables();
+
+        Window::swapBuffers();
+        Events::pollEvents();
+    }
+}
+
+void Engine::renderFrame(Batch2D& batch) {
     screen->draw(delta);
 
     Viewport viewport(Window::width, Window::height);
     GfxContext ctx(nullptr, viewport, &batch);
     gui->draw(&ctx, assets.get());
-            
-            Window::swapInterval(settings.display.swapInterval);
-        } else {
-            Window::swapInterval(1);
 }
 
+void Engine::processPostRunnables() {
+    std::lock_guard<std::recursive_mutex> lock(postRunnablesMutex);
     while (!postRunnables.empty()) {
         postRunnables.front()();
         postRunnables.pop();
     }
     scripting::process_post_runnables();
-
-        Window::swapBuffers();
-        Events::pollEvents();
-    }
 }
 
 Engine::~Engine() {
@@ -203,6 +209,7 @@ inline const std::string checkPacks(
     return "";
 }
 
+// TODO: refactor this
 void Engine::loadContent() {
     auto resdir = paths->getResources();
     ContentBuilder contentBuilder;
@@ -322,5 +329,6 @@ std::shared_ptr<Screen> Engine::getScreen() {
 }
 
 void Engine::postRunnable(runnable callback) {
+    std::lock_guard<std::recursive_mutex> lock(postRunnablesMutex);
     postRunnables.push(callback);
 }

src/engine.h

@@ -16,11 +16,13 @@
 #include <stdexcept>
 #include <string>
 #include <vector>
+#include <mutex>
 
 class Level;
 class Screen;
 class EnginePaths;
 class ResPaths;
+class Batch2D;
 
 namespace fs = std::filesystem;
 
@@ -43,6 +45,7 @@ class Engine {
     std::unique_ptr<Content> content = nullptr;
     std::unique_ptr<ResPaths> resPaths = nullptr;
     std::queue<runnable> postRunnables;
+    std::recursive_mutex postRunnablesMutex;
 
     uint64_t frame = 0;
     double lastTime = 0.0;
@@ -52,6 +55,8 @@ class Engine {
     
     void updateTimers();
     void updateHotkeys();
+    void renderFrame(Batch2D& batch);
+    void processPostRunnables();
 public:
     Engine(EngineSettings& settings, EnginePaths* paths);
     ~Engine();