fix export animation frames and add export mp4

src/canvas.cpp

@@ -2023,6 +2023,71 @@ void Canvas::export_layers_thread(std::string path)
     pb->destroy();
 }
 
+void Canvas::export_anim_frames(std::string path, std::function<void()> on_complete)
+{
+    if (App::I->check_license())
+    {
+        std::thread t([=] {
+            BT_SetTerminate();
+            export_anim_frames_thread(path);
+            if (on_complete)
+                on_complete();
+        });
+        t.detach();
+    }
+}
+
+void Canvas::export_anim_frames_thread(std::string path)
+{
+    auto pb = App::I->show_progress("Export Frames", anim_duration());
+    for (int i = 0; i < anim_duration(); i++)
+    {
+        anim_goto_frame(i);
+        export_equirectangular_thread(fmt::format("{}-{:02d}.png", path, i));
+        pb->increment();
+    }
+    pb->destroy();
+}
+
+void Canvas::export_anim_mp4(std::string path, std::function<void()> on_complete)
+{
+    if (App::I->check_license())
+    {
+        std::thread t([=] {
+            BT_SetTerminate();
+            export_anim_mp4_thread(path);
+            if (on_complete)
+                on_complete();
+        });
+        t.detach();
+    }
+}
+
+void Canvas::export_anim_mp4_thread(std::string path)
+{
+    auto pb = App::I->show_progress("Export Animation", anim_duration());
+    int fps = App::I->animation->get_fps();
+    MP4Encoder mp4;
+    int res = std::min<int>(1024, m_width);
+    mp4.init(res * 4, res * 2, 30, 2 << 20);
+    for (int i = 0; i < anim_duration(); i++)
+    {
+        Image data;
+        App::I->render_task([&]
+        {
+            anim_goto_frame(i);
+            draw_merge(false);
+            Texture2D equirect = m_layers_merge.gen_equirect({ res, res });
+            data = equirect.get_image();
+        });
+        for (int j = 0; j < 30/fps; j++)
+            mp4.encode(data);
+        pb->increment();
+    }
+    mp4.write_mp4(path);
+    pb->destroy();
+}
+
 void Canvas::export_cube_faces(std::string file_name, std::function<void()> on_complete)
 {
     if (App::I->check_license())
@@ -2032,7 +2097,7 @@ void Canvas::export_cube_faces(std::string file_name, std::function<void()> on_c
             export_cube_faces_thread(file_name);
             if (on_complete)
                 on_complete();
-            });
+        });
         t.detach();
     }
 }