add timelapse video generation on iOS and mac , fix history memory

engine/app.h

@@ -36,6 +36,15 @@ class App
 public:
     static App I;
     std::string data_path{ "." };
+    
+    std::string rec_path{ "." };
+    std::thread rec_thread;
+    bool rec_running = false;
+    int rec_count = 0;
+    std::mutex rec_mutex;
+    std::condition_variable rec_cv;
+    std::deque<std::unique_ptr<uint8_t[]>> rec_frames;
+    
     Sampler sampler;
     Texture2D tex;
     LayoutManager layout;
@@ -94,7 +103,6 @@ public:
     void create();
     void terminate();
     void clear();
-    void update_memory_usage(size_t bytes);
     void update(float dt);
     void async_start();
     void async_update();
@@ -113,12 +121,19 @@ public:
     bool key_up(kKey key);
     bool key_char(char key);
 
+    void rec_clear();
+    void rec_loop();
+    void rec_start();
+    void rec_stop();
+    void rec_export(std::string path);
+    
     void init_toolbar_main();
     void init_toolbar_draw();
     void init_sidebar();
     void init_menu_file();
     void init_menu_edit();
     void init_menu_layer();
+    void init_menu_timelapse();
     void dialog_newdoc();
     void dialog_save();
     void dialog_save_ver();
@@ -137,6 +152,8 @@ public:
 
     void brush_update();
     void title_update(std::string name, int resolution);
+    void update_memory_usage(size_t bytes);
+    void update_rec_frames();
 
     void cmd_convert(std::string pano_path, std::string out_path);
 };