Fl_Overlay_Window(int W, int H, const char *l=0);

function Create
       (W, H : in Integer;
        Text : in String := "")
    return Overlay_Window;

Fl_Overlay_Window(int X, int Y, int W, int H, const char *l=0);

function Create
       (X, Y, W, H : in Integer;
        Text       : in String := "")
    return Overlay_Window;

int can_do_overlay();

function Can_Do_Overlay
       (This : in Overlay_Window)
    return Boolean;

void flush();

procedure Flush
       (This : in out Overlay_Window);

void hide();

procedure Hide
       (This : in out Overlay_Window);

void redraw_overlay();

procedure Redraw_Overlay
       (This : in out Overlay_Window);

void resize(int, int, int, int);

procedure Resize
       (This       : in out Overlay_Window;
        X, Y, W, H : in     Integer);

void show();

procedure Show
       (This : in out Overlay_Window);

void show(int a, char **b);

procedure Show_With_Args
       (This : in out Overlay_Window);

virtual void draw_overlay()=0;

procedure Draw_Overlay
       (This : in out Overlay_Window);