add MP4Encoder class and test timelapse exporting

src/app.h

@@ -7,6 +7,8 @@
 #include "layout.h"
 #include "font.h"
 #include "rtt.h"
+#include "image.h"
+#include "mp4enc.h"
 #include "node_message_box.h"
 #include "node_settings.h"
 #include "node_popup_menu.h"
@@ -18,6 +20,10 @@
 #include "node_canvas.h"
 #include "node_dialog_layer_rename.h"
 #include "node_progress_bar.h"
+#include "node_panel_grid.h"
+#include "node_panel_quick.h"
+#include "node_input_box.h"
+#include "node_panel_animation.h"
 
 #if defined(__OBJC__) && defined(__IOS__)
 #import <Foundation/Foundation.h>
@@ -37,11 +43,6 @@
 #include <GLFW/glfw3.h>
 #endif
 
-#include "node_panel_grid.h"
-#include "node_panel_quick.h"
-#include "node_input_box.h"
-#include "node_panel_animation.h"
-
 struct VRController
 {
     enum class kButton : uint8_t
@@ -94,7 +95,8 @@ public:
     int rec_count = 0;
     std::mutex rec_mutex;
     std::condition_variable rec_cv;
-    std::deque<std::unique_ptr<uint8_t[]>> rec_frames;
+    std::deque<std::unique_ptr<Image>> rec_frames;
+    std::unique_ptr<MP4Encoder> m_encoder;
 
     RTT uirtt;
     Sampler sampler;