Widget.addTickCallback

Queues an animation frame update and adds a callback to be called before each frame. Until the tick callback is removed, it will be called frequently (usually at the frame rate of the output device or as quickly as the application can be repainted, whichever is slower). For this reason, is most suitable for handling graphics that change every frame or every few frames. The tick callback does not automatically imply a relayout or repaint. If you want a repaint or relayout, and aren't changing widget properties that would trigger that (for example, changing the text of a GtkLabel), then you will have to call gtk_widget_queue_resize() or gtk_widget_queue_draw_area() yourself. gdk_frame_clock_get_frame_time() should generally be used for timing continuous animations and gdk_frame_timings_get_predicted_presentation_time() if you are trying to display isolated frames at particular times. This is a more convenient alternative to connecting directly to the "update" signal of GdkFrameClock, since you don't have to worry about when a GdkFrameClock is assigned to a widget.