virtual int64_t get_drag_position() = 0;
virtual void update_gui() { return; };
void create_objects();
+ int get_track_w();
+ int get_track_h();
void bound();
static void draw_boundary(VFrame *out, int x, int y, int w, int h);
int handle_event();
int grab_event(XEvent *event);
+ int handle_ungrab();
MWindow *mwindow;
int grabbed, dragging, pending;