From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 8 Sep 2019 14:17:02 +0000 (+0300)
Subject: Add a system for animating widgets
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgltk.git;a=commitdiff_plain;h=7d8609bec44adcab67b0c1a78d560ef76afded8d

Add a system for animating widgets
---

diff --git a/source/container.cpp b/source/container.cpp
index 91fa487..62e6e12 100644
--- a/source/container.cpp
+++ b/source/container.cpp
@@ -30,6 +30,8 @@ void Container::add(Widget &wdg)
 {
 	wdg.set_parent(this);
 	children.push_back(create_child(&wdg));
+	if(wdg.get_animation_interval())
+		check_animation_interval();
 	on_child_added(wdg);
 }
 
@@ -41,6 +43,8 @@ void Container::remove(Widget &wdg)
 			wdg.set_parent(0);
 			delete *i;
 			children.erase(i);
+			if(wdg.get_animation_interval())
+				check_animation_interval();
 			on_child_removed(wdg);
 			return;
 		}
@@ -165,6 +169,20 @@ Widget *Container::get_final_input_focus() const
 	return input_focus;
 }
 
+void Container::check_animation_interval()
+{
+	Time::TimeDelta shortest;
+	for(list<Child *>::const_iterator i=children.begin(); i!=children.end(); ++i)
+	{
+		const Time::TimeDelta &child_iv = (*i)->widget->get_animation_interval();
+		if(child_iv && (!shortest || child_iv<shortest))
+			shortest = child_iv;
+	}
+
+	if(shortest!=anim_interval)
+		set_animation_interval(shortest);
+}
+
 void Container::button_press(int x, int y, unsigned btn)
 {
 	if(Widget *child = get_pointer_target(x, y, false))
@@ -310,6 +328,24 @@ bool Container::navigate(Navigation nav)
 		return false;
 }
 
+void Container::animate(const Time::TimeDelta &dt)
+{
+	for(list<Child *>::iterator i=children.begin(); i!=children.end(); ++i)
+	{
+		const Time::TimeDelta &child_iv = (*i)->widget->get_animation_interval();
+		if(!child_iv)
+			continue;
+
+		(*i)->time_since_animate += dt;
+		if((*i)->time_since_animate>=child_iv)
+		{
+			Time::TimeDelta child_dt = (*i)->time_since_animate;
+			(*i)->time_since_animate = min((*i)->time_since_animate-child_iv, child_iv);
+			(*i)->widget->animate(child_dt);
+		}
+	}
+}
+
 void Container::on_reparent()
 {
 	for(list<Child *>::iterator i=children.begin(); i!=children.end(); ++i)
@@ -329,6 +365,7 @@ Container::Child::Child(Container &c, Widget *w):
 	widget->signal_request_focus.connect(sigc::mem_fun(this, &Child::request_focus));
 	widget->signal_grab_pointer.connect(sigc::mem_fun(this, &Child::grab_pointer));
 	widget->signal_ungrab_pointer.connect(sigc::mem_fun(this, &Child::ungrab_pointer));
+	widget->signal_request_animation.connect(sigc::mem_fun(this, &Child::request_animation));
 }
 
 Container::Child::~Child()
@@ -377,5 +414,12 @@ void Container::Child::ungrab_pointer()
 	}
 }
 
+void Container::Child::request_animation(const Time::TimeDelta &interval)
+{
+	if(!interval)
+		time_since_animate = Time::zero;
+	container.check_animation_interval();
+}
+
 } // namespace GLtk
 } // namespace Msp
diff --git a/source/container.h b/source/container.h
index b463ff2..f68d81f 100644
--- a/source/container.h
+++ b/source/container.h
@@ -24,6 +24,7 @@ protected:
 	{
 		Container &container;
 		Widget *widget;
+		Time::TimeDelta time_since_animate;
 
 		Child(Container &, Widget *);
 		virtual ~Child();
@@ -32,6 +33,7 @@ protected:
 		void request_focus();
 		void grab_pointer();
 		void ungrab_pointer();
+		void request_animation(const Time::TimeDelta &);
 	};
 
 	std::list<Child *> children;
@@ -66,6 +68,10 @@ public:
 	Widget *get_input_focus() const { return input_focus; }
 	Widget *get_final_input_focus() const;
 
+private:
+	void check_animation_interval();
+
+public:
 	virtual void button_press(int, int, unsigned);
 	virtual void button_release(int, int, unsigned);
 	virtual void pointer_motion(int, int);
@@ -81,6 +87,7 @@ public:
 	virtual bool character(wchar_t);
 	virtual void focus_out();
 	virtual bool navigate(Navigation);
+	virtual void animate(const Time::TimeDelta &);
 protected:
 	virtual void on_reparent();
 	virtual void on_child_added(Widget &) { }
diff --git a/source/root.cpp b/source/root.cpp
index 4a2d611..ad1ca5b 100644
--- a/source/root.cpp
+++ b/source/root.cpp
@@ -91,6 +91,12 @@ Root::~Root()
 
 void Root::tick()
 {
+	Time::TimeStamp t = Time::now();
+	Time::TimeDelta dt = (last_tick ? t-last_tick : Time::zero);
+	last_tick = t;
+
+	animate(dt);
+
 	if(tooltip_timeout && Time::now()>tooltip_timeout)
 	{
 		std::string tip;
diff --git a/source/root.h b/source/root.h
index 7d5a592..5de3626 100644
--- a/source/root.h
+++ b/source/root.h
@@ -39,6 +39,7 @@ private:
 	int pointer_x;
 	int pointer_y;
 	Time::TimeStamp tooltip_timeout;
+	Time::TimeStamp last_tick;
 	Widget *tooltip_target;
 	Msp::GL::Camera camera;
 	Msp::GL::Program *shprog;
diff --git a/source/widget.cpp b/source/widget.cpp
index aa05675..b40aa75 100644
--- a/source/widget.cpp
+++ b/source/widget.cpp
@@ -188,6 +188,20 @@ void Widget::set_state(State mask, State bits)
 		rebuild();
 }
 
+void Widget::set_animation_interval(const Time::TimeDelta &iv)
+{
+	if(iv<Time::zero)
+		throw invalid_argument("Widget::set_animation_interval");
+
+	anim_interval = iv;
+	signal_request_animation.emit(anim_interval);
+}
+
+void Widget::stop_animation()
+{
+	set_animation_interval(Time::zero);
+}
+
 void Widget::rebuild()
 {
 	if(!style)
diff --git a/source/widget.h b/source/widget.h
index eb8fa23..94ee7f6 100644
--- a/source/widget.h
+++ b/source/widget.h
@@ -40,6 +40,7 @@ public:
 	sigc::signal<void> signal_request_focus;
 	sigc::signal<void> signal_grab_pointer;
 	sigc::signal<void> signal_ungrab_pointer;
+	sigc::signal<void, const Time::TimeDelta &> signal_request_animation;
 
 protected:
 	Geometry geom;
@@ -51,6 +52,7 @@ protected:
 	Container *parent;
 	std::string tooltip;
 	PartCache part_cache;
+	Time::TimeDelta anim_interval;
 
 	Widget();
 private:
@@ -124,6 +126,12 @@ protected:
 public:
 	State get_state() const { return state; }
 
+protected:
+	void set_animation_interval(const Time::TimeDelta &);
+	void stop_animation();
+public:
+	const Time::TimeDelta &get_animation_interval() const { return anim_interval; }
+
 protected:
 	void rebuild();
 	virtual void rebuild_special(const Part &);
@@ -149,6 +157,7 @@ public:
 	virtual void focus_in();
 	virtual void focus_out();
 	virtual bool navigate(Navigation) { return false; }
+	virtual void animate(const Time::TimeDelta &) { }
 protected:
 	virtual void on_geometry_change() { }
 	virtual void on_style_change() { }