menu_view: use timer for animation timing

This patch removes the use of sync signals as time source. The animation
phase is now timed using a timer connection as tick source while sync
signals are used for scheduling the redraws.

Issue #5347

repos/gems/src/app/menu_view/button_widget.h

@@ -85,7 +85,7 @@ struct Menu_view::Button_widget : Widget, Animator::Item
 				 * or changing the selection state of a button, the transition
 				 * must be quick to provide a responsive feel.
 				 */
-				enum { SLOW = 80, MEDIUM = 40, FAST = 3 };
+				enum { SLOW = 40, MEDIUM = 20, FAST = 2 };
 				int steps = SLOW;
 				if (_hovered && !new_hovered)  steps = MEDIUM;
 				if (!_hovered && new_hovered)  steps = FAST;

repos/gems/src/app/menu_view/cursor.h

@@ -122,7 +122,7 @@ class Menu_view::Cursor : List_model<Cursor>::Element
 
 		void update(Xml_node const &node)
 		{
-			_move_to(_position_from_xml_node(node), Steps{12});
+			_move_to(_position_from_xml_node(node), Steps{6});
 		}
 };
 

repos/gems/src/app/menu_view/dialog.h

@@ -47,9 +47,9 @@ struct Menu_view::Dialog : List_model<Dialog>::Element
 
 	struct Action : Interface
 	{
-		virtual void trigger_redraw() = 0;
 		virtual void hover_changed() = 0;
 		virtual void observed_seq_number(Input::Seq_number) = 0;
+		virtual Ticks now() = 0;
 	};
 
 	Action &_action;
@@ -72,6 +72,15 @@ struct Menu_view::Dialog : List_model<Dialog>::Element
 
 	void _handle_input();
 
+	Signal_handler<Dialog> _gui_sync_handler {
+		_env.ep(), *this, &Dialog::_handle_gui_sync };
+
+	void _handle_gui_sync();
+
+	bool _gui_sync_enabled = false;
+
+	Ticks _previous_sync { };
+
 	Constructible<Gui_buffer> _buffer { };
 
 	Gui::View_ref _view_ref { };
@@ -151,7 +160,7 @@ struct Menu_view::Dialog : List_model<Dialog>::Element
 			_root_widget.gen_hover_model(xml, _hovered_position);
 	}
 
-	void redraw()
+	void _redraw()
 	{
 		if (!_redraw_scheduled)
 			return;
@@ -190,7 +199,7 @@ struct Menu_view::Dialog : List_model<Dialog>::Element
 
 	bool hovered() const { return _hovered; }
 
-	void animate()
+	void _animate()
 	{
 		bool const progress = _local_animator.active();
 
@@ -200,9 +209,14 @@ struct Menu_view::Dialog : List_model<Dialog>::Element
 			_redraw_scheduled = true;
 	}
 
-	bool animation_in_progress() const { return _local_animator.active(); }
+	void enforce_font_sytle_change()
+	{
+		_handle_dialog();
 
-	bool redraw_scheduled() const { return _redraw_scheduled; }
+		/* fast-forward geometry animation */
+		while (_local_animator.active())
+			_animate();
+	}
 
 	/*
 	 * List_model
@@ -237,7 +251,13 @@ void Menu_view::Dialog::_handle_dialog()
 	_redraw_scheduled = true;
 
 	_action.hover_changed();
-	_action.trigger_redraw();
+
+	if (!_gui_sync_enabled) {
+		_gui.framebuffer.sync_sigh(_gui_sync_handler);
+		_gui_sync_enabled = true;
+	}
+
+	_handle_gui_sync();
 }
 
 
@@ -287,4 +307,25 @@ void Menu_view::Dialog::_handle_input()
 		_action.hover_changed();
 }
 
+
+void Menu_view::Dialog::_handle_gui_sync()
+{
+	Ticks const now = _action.now();
+
+	Ticks const passed_ticks { now.cs - _previous_sync.cs };
+
+	for (unsigned i = 0; i < passed_ticks.cs; i++)
+		_animate();
+
+	if (passed_ticks.cs)
+		_redraw();
+
+	/* deactivate sync signalling when idle */
+	if (_gui_sync_enabled && !_local_animator.active()) {
+		_gui.framebuffer.sync_sigh(Signal_context_capability());
+		_gui_sync_enabled = false;
+	}
+	_previous_sync = now;
+}
+
 #endif /* _DIALOG_H_ */

repos/gems/src/app/menu_view/label_widget.h

@@ -89,7 +89,7 @@ struct Menu_view::Label_widget : Widget, Cursor::Glyph_position
 		_hover      = node.attribute_value("hover", false);
 
 		_factory.styles.with_label_style(node, [&] (Label_style style) {
-			_color.fade_to(style.color, Animated_color::Steps{80}); });
+			_color.fade_to(style.color, Animated_color::Steps{40}); });
 
 		if (node.has_attribute("text")) {
 			_text       = node.attribute_value("text", _text);

repos/gems/src/app/menu_view/main.cc

@@ -83,45 +83,14 @@ struct Menu_view::Main : Dialog::Action
 
 	} _input_seq_number { };
 
-	struct Frame { uint64_t count; };
-
-	/*
-	 * Timer used for animating widgets
-	 */
-	struct Frame_timer : Timer::Connection
-	{
-		enum { PERIOD = 10 };
-
-		Frame curr_frame() const { return { elapsed_ms() / PERIOD }; }
-
-		void schedule() { trigger_once((Genode::uint64_t)Frame_timer::PERIOD*1000); }
-
-		Frame_timer(Env &env) : Timer::Connection(env) { }
-
-	} _timer { _env };
-
-	void _handle_frame_timer();
+	Timer::Connection _timer { _env };
 
 	/**
 	 * Dialog::Action
 	 */
-	void trigger_redraw() override
+	Ticks now() override
 	{
-		/*
-		 * If we have not processed a period for at least one frame, perform the
-		 * processing immediately. This way, we avoid latencies when the dialog
-		 * model is updated sporadically.
-		 */
-		Frame const curr_frame = _timer.curr_frame();
-		if (curr_frame.count != _last_frame.count) {
-
-			if (curr_frame.count - _last_frame.count > 10)
-				_last_frame = curr_frame;
-
-			_handle_frame_timer();
-		} else {
-			_timer.schedule();
-		}
+		return { .cs = _timer.curr_time().trunc_to_plain_ms().value / 10 };
 	}
 
 	/**
@@ -137,38 +106,16 @@ struct Menu_view::Main : Dialog::Action
 		_input_seq_number.update(seq);
 	}
 
-	Signal_handler<Main> _frame_timer_handler = {
-		_env.ep(), *this, &Main::_handle_frame_timer};
-
 	Constructible<Genode::Expanding_reporter> _hover_reporter { };
 
 	void _update_hover_report();
 
-	/**
-	 * Frame of last call of 'handle_frame_timer'
-	 */
-	Frame _last_frame { };
-
-	/**
-	 * Number of frames between two redraws
-	 */
-	static constexpr unsigned REDRAW_PERIOD = 2;
-
-	/**
-	 * Counter used for triggering redraws. Incremented in each frame-timer
-	 * period, wraps at 'REDRAW_PERIOD'. The redraw is performed when the
-	 * counter wraps.
-	 */
-	unsigned _frame_cnt = 0;
-
 	Main(Env &env, Vfs::Env &libc_vfs_env)
 	:
 		_env(env), _vfs_env(libc_vfs_env)
 	{
 		_config.sigh(_config_handler);
 		_config_handler.local_submit(); /* apply initial configuration */
-
-		_timer.sigh(_frame_timer_handler);
 	}
 };
 
@@ -239,57 +186,10 @@ void Menu_view::Main::_handle_config()
 	/* re-assign font pointers in labels (needed due to font style change) */
 	if (!_styles.up_to_date()) {
 		_dialogs.for_each([&] (Dialog &dialog) {
-			dialog._handle_dialog();
-
-			/* fast-forward geometry animation on font changes */
-			while (dialog.animation_in_progress())
-				dialog.animate();
-		});
+			dialog.enforce_font_sytle_change(); });
 
 		_styles.flush_outdated_styles();
 	}
-	trigger_redraw();
-}
-
-
-void Menu_view::Main::_handle_frame_timer()
-{
-	_frame_cnt++;
-
-	Frame const curr_frame = _timer.curr_frame();
-
-	unsigned const passed_frames =
-		max(unsigned(curr_frame.count - _last_frame.count), 4U);
-
-	if (passed_frames > 0)
-		_dialogs.for_each([&] (Dialog &dialog) {
-			for (unsigned i = 0; i < passed_frames; i++)
-				dialog.animate(); });
-
-	bool any_redraw_scheduled = false;
-	_dialogs.for_each([&] (Dialog const &dialog) {
-		any_redraw_scheduled |= dialog.redraw_scheduled(); });
-
-	_last_frame = curr_frame;
-
-	bool const redraw_skipped = any_redraw_scheduled && (_frame_cnt < REDRAW_PERIOD);
-
-	if (!redraw_skipped) {
-		_frame_cnt = 0;
-		_dialogs.for_each([&] (Dialog &dialog) {
-			dialog.redraw(); });
-	}
-
-	bool any_animation_in_progress = false;
-	_dialogs.for_each([&] (Dialog const &dialog) {
-		any_animation_in_progress |= dialog.animation_in_progress(); });
-
-	/*
-	 * Deactivate timer periods when idle, activate timer when an animation is
-	 * in progress or a redraw is pending.
-	 */
-	if (any_animation_in_progress || redraw_skipped)
-		_timer.schedule();
 }
 
 

repos/gems/src/app/menu_view/types.h

@@ -36,6 +36,8 @@ namespace Menu_view {
 	using Point = Surface_base::Point;
 	using Area  = Surface_base::Area;
 	using Rect  = Surface_base::Rect;
+
+	struct Ticks { uint64_t cs; /* centi-seconds (10 ms) */ };
 }
 
 #endif /* _TYPES_H_ */

repos/gems/src/app/menu_view/widget.h

@@ -110,7 +110,7 @@ class Menu_view::Widget : List_model<Widget>::Element
 			return node.attribute_value("version", Version());
 		}
 
-		static Animated_rect::Steps motion_steps() { return { 60 }; };
+		static Animated_rect::Steps motion_steps() { return { 30 }; };
 
 	protected: