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Implement fade transitions using Gtk.Stack

by soreau, Saturday, 13 September 2025, 02:52:07 (1757731927), pushed by soreau, Saturday, 13 September 2025, 02:52:17 (1757731937)

Author identity: Scott Moreau <oreaus@gmail.com>

a0d3f2cc911a2c77ba1a31ab894d18d2c798b93c

main.py

@@ -107,16 +107,14 @@ class PanoramaBG(Gtk.Application):

                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                        yaml_file = yaml_loader.load(config_file)
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                            
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                        monitors = self.display.get_monitors()
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                        
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                        for monitor in monitors:
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                            background_window = BackgroundWindow(self, monitor)
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                            monitor.background_window = background_window
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                        
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                            if monitor.get_connector() in yaml_file["monitors"]:
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                            background_window.put_sources(yaml_file["monitors"][monitor.get_connector()]["sources"])
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                                background_window.time_per_image = yaml_file["monitors"][monitor.get_connector()]["time_per_image"]
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                            background_window.change_image()
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                            background_window.picture.set_content_fit(FITTING_MODES[yaml_file["monitors"][monitor.get_connector()]["fitting_mode"]])
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                            background_window.put_sources(yaml_file["monitors"][monitor.get_connector()]["sources"])
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                            background_window.picture1.set_content_fit(FITTING_MODES[yaml_file["monitors"][monitor.get_connector()]["fitting_mode"]])
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                            background_window.picture2.set_content_fit(FITTING_MODES[yaml_file["monitors"][monitor.get_connector()]["fitting_mode"]])
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                            
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                            background_window.present()
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                            
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        

@@ -208,6 +206,7 @@ class BackgroundWindow(Gtk.Window):

                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    self.sources = []
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    self.time_per_image = 0
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    self.current_timeout = None
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.pic1 = True
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                            
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    Gtk4LayerShell.init_for_window(self)
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    Gtk4LayerShell.set_namespace(self, "com.roundabout_host.panorama.background")
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        

@@ -219,8 +218,17 @@ class BackgroundWindow(Gtk.Window):

                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    Gtk4LayerShell.set_anchor(self, Gtk4LayerShell.Edge.BOTTOM, True)
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    Gtk4LayerShell.set_anchor(self, Gtk4LayerShell.Edge.RIGHT, True)
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                            
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.picture = Gtk.Picture()
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.set_child(self.picture)
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.picture1 = Gtk.Picture()
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.picture2 = Gtk.Picture()
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.stack = Gtk.Stack()
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.stack.set_transition_type(Gtk.StackTransitionType.CROSSFADE)
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                        
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.stack.add_child(self.picture1)
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.stack.add_child(self.picture2)
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                        
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.stack.set_visible_child(self.picture1)
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.set_child(self.stack)
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                        
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                            
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                def put_sources(self, sources):
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    self.all_sources = []
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        

@@ -232,10 +240,20 @@ class BackgroundWindow(Gtk.Window):

                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                        else:
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                            self.all_sources.append(path)
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    self.all_sources = self.all_sources
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.stack.set_transition_duration(1000)
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                now = GLib.DateTime.new_now_local()
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.change_image()
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                            
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                def change_image(self):
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    now = GLib.DateTime.new_now_local()
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.picture.set_filename(str(self.all_sources[now.to_unix() // self.time_per_image % len(self.all_sources)]))
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                # Ping pong between images is required for transition
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                if self.pic1:
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                    self.picture1.set_filename(str(self.all_sources[now.to_unix() // self.time_per_image % len(self.all_sources)]))
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                    self.stack.set_visible_child(self.picture1)
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                else:
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                    self.picture2.set_filename(str(self.all_sources[now.to_unix() // self.time_per_image % len(self.all_sources)]))
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                    self.stack.set_visible_child(self.picture2)
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                                self.pic1 = not self.pic1
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    time_until_next = self.time_per_image - now.to_unix() % self.time_per_image
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    self.current_timeout = GLib.timeout_add_seconds(time_until_next, self.change_image)
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
                                            
                                                    return False