Trim main task queue, recording label, and canvas draw callbacks

src/app.cpp

@@ -214,6 +214,7 @@ void App::initLog()
 namespace pp::panopainter
 {
     bool process_legacy_recording_worker_iteration(App& app);
+    void update_legacy_recording_frame_label(App& app);
 }
 
 bool App::check_license()
@@ -566,14 +567,7 @@ void App::update_memory_usage(size_t bytes)
 
 void App::update_rec_frames()
 {
-    if (auto txt = layout[main_id]->find<NodeText>("txt-rec"))
-    {
-        const auto label = pp::app::make_recording_frame_label(
-            rec_running,
-            Canvas::I->m_encoder != nullptr,
-            Canvas::I->m_encoder ? Canvas::I->m_encoder->frames_count() : 0);
-        txt->set_text(label.text.c_str());
-    }
+    pp::panopainter::update_legacy_recording_frame_label(*this);
 }
 
 int App::res_from_index(int i)

src/legacy_canvas_draw_merge_services.h

@@ -529,7 +529,25 @@ template <typename LayerMergeT, typename SamplerT, typename FacePlaneT, typename
                 .unbind_layer_texture = [layer_merge, plane_index] {
                     layer_merge->rtt(plane_index).unbindTexture();
                 },
-            });
+        });
+    };
+}
+
+template <typename LayerT, typename FacePlaneT, typename SetActiveTextureUnit>
+[[nodiscard]] inline auto make_legacy_canvas_draw_merge_layer_frame_draw(
+    LayerT* layer,
+    FacePlaneT* face_plane,
+    SetActiveTextureUnit set_active_texture_unit,
+    int plane_index,
+    float layer_opacity)
+{
+    return [layer, face_plane, set_active_texture_unit, plane_index, layer_opacity](int frame, float onion_alpha) {
+        ShaderManager::u_float(kShaderUniform::Alpha, layer_opacity * onion_alpha);
+        set_active_texture_unit(0);
+        layer->rtt(plane_index, frame).bindTexture();
+        face_plane->draw_fill();
+        set_active_texture_unit(0);
+        layer->rtt(plane_index, frame).unbindTexture();
     };
 }
 

src/legacy_recording_services.cpp

@@ -4,11 +4,14 @@
 
 #include "app.h"
 #include "canvas.h"
+#include "app_core/app_status.h"
 #include "legacy_app_dialog_services.h"
 #include "legacy_ui_overlay_services.h"
 #include "node_progress_bar.h"
 
 namespace pp::panopainter {
+void update_legacy_recording_frame_label(App& app);
+
 namespace {
 
 pp::app::RecordingWorkerIterationPlan make_recording_worker_iteration_plan(App& app)
@@ -42,9 +45,25 @@ void encode_recording_frame(
     LOG("rec frame encoded");
 
     if (plan.update_frame_label)
-        app.update_rec_frames();
+        update_legacy_recording_frame_label(app);
 }
 
+} // namespace
+
+void update_legacy_recording_frame_label(App& app)
+{
+    if (auto txt = app.layout[app.main_id]->find<NodeText>("txt-rec"))
+    {
+        const auto label = pp::app::make_recording_frame_label(
+            app.rec_running,
+            Canvas::I->m_encoder != nullptr,
+            Canvas::I->m_encoder ? Canvas::I->m_encoder->frames_count() : 0);
+        txt->set_text(label.text.c_str());
+    }
+}
+
+namespace {
+
 class LegacyRecordingServices final : public pp::app::RecordingServices {
 public:
     explicit LegacyRecordingServices(App& app) noexcept
@@ -54,7 +73,7 @@ public:
 
     void start_thread() override
     {
-        app_.update_rec_frames();
+        update_legacy_recording_frame_label(app_);
         app_.rec_thread = std::jthread(&App::rec_loop, &app_);
     }
 
@@ -65,7 +84,7 @@ public:
         app_.rec_cv.notify_all();
         if (app_.rec_thread.joinable())
             app_.rec_thread.join();
-        app_.update_rec_frames();
+        update_legacy_recording_frame_label(app_);
     }
 
     void delete_recorded_files() override
@@ -80,7 +99,7 @@ public:
 
     void update_frame_label() override
     {
-        app_.update_rec_frames();
+        update_legacy_recording_frame_label(app_);
     }
 
     void begin_export(int progress_total) override

src/main.cpp

@@ -54,8 +54,6 @@ struct RetainedState
     std::map<kKey, int> vkey_map;
     wchar_t window_title[512]{};
     std::jthread hmd_renderer;
-    std::deque<std::packaged_task<void()>> main_tasklist;
-    std::mutex main_task_mutex;
     float timer_stylus = 0;
     float timer_ink_touch = 0;
     float timer_ink_pen = 0;
@@ -72,6 +70,46 @@ RetainedState& retained_state()
     return state;
 }
 
+namespace {
+
+struct RetainedMainTaskQueue final
+{
+    std::deque<std::packaged_task<void()>> tasklist;
+    std::mutex task_mutex;
+};
+
+RetainedMainTaskQueue& retained_main_task_queue()
+{
+    static RetainedMainTaskQueue queue;
+    return queue;
+}
+
+template <typename Callable>
+void enqueue_main_task(Callable&& task)
+{
+    auto& queue = retained_main_task_queue();
+    std::lock_guard<std::mutex> lock(queue.task_mutex);
+    queue.tasklist.emplace_back(std::forward<Callable>(task));
+}
+
+void drain_main_tasks()
+{
+    std::deque<std::packaged_task<void()>> working_list;
+    {
+        auto& queue = retained_main_task_queue();
+        std::lock_guard<std::mutex> lock(queue.task_mutex);
+        working_list = std::move(queue.tasklist);
+    }
+
+    while (!working_list.empty())
+    {
+        working_list.front()();
+        working_list.pop_front();
+    }
+}
+
+}
+
 std::atomic<int> vr_frames{0};
 std::atomic<int> running{-1};
 std::atomic_bool vr_running{false};
@@ -163,8 +201,7 @@ std::string GetLastErrorAsString()
 void destroy_window()
 {
     auto& state = retained_state();
-    std::lock_guard<std::mutex> lock(state.main_task_mutex);
-    state.main_tasklist.emplace_back([hWnd = state.hWnd] {
+    enqueue_main_task([hWnd = state.hWnd] {
         PostMessage(hWnd, WM_USER_CLOSE, 0, 0);
     });
 }
@@ -225,8 +262,7 @@ void win32_update_fps(int frames)
         swprintf_s(title_fps, L"%s - %d fps", state.window_title, frames);
 
     {
-        std::lock_guard<std::mutex> lock(state.main_task_mutex);
-        state.main_tasklist.emplace_back([hWnd = state.hWnd] {
+        enqueue_main_task([hWnd = state.hWnd] {
             SetWindowText(hWnd, title_fps);
         });
     }
@@ -991,22 +1027,7 @@ int main(int argc, char** argv)
         }
 
         // list of tasks for the main thread
-        {
-            std::deque<std::packaged_task<void()>> working_list;
-            {
-                std::lock_guard<std::mutex> lock(state.main_task_mutex);
-                working_list = std::move(state.main_tasklist);
-            }
-
-            if (!working_list.empty())
-            {
-                while (!working_list.empty())
-                {
-                    working_list.front()();
-                    working_list.pop_front();
-                }
-            }
-        }
+        drain_main_tasks();
     }
     // Clean up
     WacomTablet::I.terminate();

src/node_canvas.cpp

@@ -469,14 +469,12 @@ void NodeCanvas::draw()
                     m_canvas->m_plane_transform[plane_index] * 
                     glm::translate(glm::vec3(0, 0, -1));
 
-                const auto draw_layer_frame = [&](int frame, float onion_alpha) {
-                    ShaderManager::u_float(kShaderUniform::Alpha, m_canvas->m_layers[layer_index]->m_opacity * onion_alpha);
-                    set_active_texture_unit(0);
-                    m_canvas->m_layers[layer_index]->rtt(plane_index, frame).bindTexture();
-                    m_face_plane.draw_fill();
-                    set_active_texture_unit(0);
-                    m_canvas->m_layers[layer_index]->rtt(plane_index, frame).unbindTexture();
-                };
+                const auto draw_layer_frame = pp::panopainter::make_legacy_canvas_draw_merge_layer_frame_draw(
+                    m_canvas->m_layers[layer_index].get(),
+                    &m_face_plane,
+                    set_active_texture_unit,
+                    plane_index,
+                    m_canvas->m_layers[layer_index]->m_opacity);
 
                 pp::panopainter::execute_legacy_canvas_draw_merge_layer_plane(
                     m_canvas->m_current_stroke && m_canvas->m_current_mode == kCanvasMode::Erase && m_canvas->m_show_tmp && m_canvas->m_current_layer_idx == layer_index,