Make it possible to choose which card is the master clock.

diff --git a/glwidget.cpp b/glwidget.cpp
index e8c241669a9fab11e66185a0446b2b3f1628198e..bf3ac13a6a6cb53df3f332785af6e8c980f291b4 100644 (file)
--- a/glwidget.cpp
+++ b/glwidget.cpp
@@ -211,6 +211,7 @@ void GLWidget::show_context_menu(unsigned signal_num, const QPoint &pos)
        mode_submenu.setTitle("Input mode");
        menu.addMenu(&mode_submenu);
 
+       // --- End of card-dependent choices ---
 
        // Add an audio source selector.
        QAction *audio_source_action = new QAction("Use as audio source", &menu);
@@ -221,10 +222,21 @@ void GLWidget::show_context_menu(unsigned signal_num, const QPoint &pos)
        }
        menu.addAction(audio_source_action);
 
+       // And a master clock selector.
+       QAction *master_clock_action = new QAction("Use as master clock", &menu);
+       master_clock_action->setCheckable(true);
+       if (global_mixer->get_master_clock() == signal_num) {
+               master_clock_action->setChecked(true);
+               master_clock_action->setEnabled(false);
+       }
+       menu.addAction(master_clock_action);
+
        // Show the menu and look at the result.
        QAction *selected_item = menu.exec(global_pos);
        if (selected_item == audio_source_action) {
                global_mixer->set_audio_source(signal_num);
+       } else if (selected_item == master_clock_action) {
+               global_mixer->set_master_clock(signal_num);
        } else if (selected_item != nullptr) {
                QList<QVariant> selected = selected_item->data().toList();
                if (selected[0].toString() == "video_mode") {

diff --git a/mixer.cpp b/mixer.cpp
index 50c93e8c018a9f3b077830b77788f8dffbee5b8c..2802329b136c60c69b9f760ce812150bb7fa49a7 100644 (file)
--- a/mixer.cpp
+++ b/mixer.cpp
@@ -605,8 +605,9 @@ void Mixer::thread_func()
                bool has_new_frame[MAX_CARDS] = { false };
                int num_samples[MAX_CARDS] = { 0 };
 
-               // TODO: Make configurable, and with a timeout.
-               unsigned master_card_index = 0;
+               // TODO: Add a timeout.
+               unsigned master_card_index = theme->map_signal(master_clock_channel);
+               assert(master_card_index < num_cards);
 
                get_one_frame_from_each_card(master_card_index, new_frames, has_new_frame, num_samples);
                schedule_audio_resampling_tasks(new_frames[master_card_index].dropped_frames, num_samples[master_card_index], new_frames[master_card_index].length);
@@ -715,7 +716,12 @@ void Mixer::get_one_frame_from_each_card(unsigned master_card_index, CaptureCard
                card->fractional_samples = num_samples_times_timebase % TIMEBASE;
                assert(num_samples[card_index] >= 0);
 
-               if (card_index != master_card_index) {
+               if (card_index == master_card_index) {
+                       // We don't use the queue length policy for the master card,
+                       // but we will if it stops being the master. Thus, clear out
+                       // the policy in case we switch in the future.
+                       card->queue_length_policy.reset(card_index);
+               } else {
                        // If we have excess frames compared to the policy for this card,
                        // drop frames from the head.
                        card->queue_length_policy.update_policy(card->new_frames.size());

diff --git a/mixer.h b/mixer.h
index c68ad1b81a1fd527a2c9a29c30337e724c9fd7a6..2b006822ee14d4fd1393a1ffc7e1dafcf030027a 100644 (file)
--- a/mixer.h
+++ b/mixer.h
@@ -187,6 +187,16 @@ public:
                audio_source_channel = channel;
        }
 
+       unsigned get_master_clock() const
+       {
+               return master_clock_channel;
+       }
+
+       void set_master_clock(unsigned channel)
+       {
+               master_clock_channel = channel;
+       }
+
        void set_signal_mapping(int signal, int card)
        {
                return theme->set_signal_mapping(signal, card);
@@ -352,6 +362,7 @@ private:
        std::unique_ptr<movit::ResourcePool> resource_pool;
        std::unique_ptr<Theme> theme;
        std::atomic<unsigned> audio_source_channel{0};
+       std::atomic<unsigned> master_clock_channel{0};
        std::unique_ptr<movit::EffectChain> display_chain;
        GLuint cbcr_program_num;  // Owned by <resource_pool>.
        GLuint cbcr_vbo;  // Holds position and texcoord data.