Replace brute pixmap allocations by the lazy Gtk_tools.pixmap_in_drawing_area

sw/ground_segment/cockpit/compass.ml

@@ -1,3 +1,29 @@
+(*
+* $Id$
+*
+* Compass display for a manned vehicle
+*  
+* Copyright (C) 2004-2009 ENAC, Pascal Brisset, Antoine Drouin
+*
+* This file is part of paparazzi.
+*
+* paparazzi is free software; you can redistribute it and/or modify
+* it under the terms of the GNU General Public License as published by
+* the Free Software Foundation; either version 2, or (at your option)
+* any later version.
+*
+* paparazzi is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with paparazzi; see the file COPYING.  If not, write to
+* the Free Software Foundation, 59 Temple Place - Suite 330,
+* Boston, MA 02111-1307, USA. 
+*
+*)
+
 open Printf
 open Latlong
 
@@ -23,12 +49,13 @@ let circle = fun (dr:GDraw.pixmap) (x,y) r ->
   let points = Array.init n
       (fun i ->
 	let a = float i /. float n *. 2.*.pi in
-	(x + truncate (r*.cos a), x + truncate (r*.sin a))) in
+	(x + truncate (r*.cos a), y + truncate (r*.sin a))) in
   dr#polygon (Array.to_list points)
       
-let draw = fun da desired_course course_opt distance ->
+let draw = fun (da_object:Gtk_tools.pixmap_in_drawin_area) desired_course course_opt distance ->
+  let da = da_object#drawing_area in
   let {Gtk.width=width; height=height} = da#misc#allocation in
-  let dr = GDraw.pixmap ~width ~height ~window:da () in
+  let dr = da_object#get_pixmap () in
   dr#set_foreground background;
   dr#rectangle ~x:0 ~y:0 ~width ~height ~filled:true ();
   let s = (min width height) / 8 in
@@ -103,8 +130,8 @@ let _ =
   let quit = fun () -> GMain.Main.quit (); exit 0 in
   ignore (window#connect#destroy ~callback:quit);
 
-  let da = GMisc.drawing_area ~width ~height ~packing:window#add () in
+  let da = new Gtk_tools.pixmap_in_drawin_area ~width ~height ~packing:window#add () in
-  da#misc#realize ();
+  da#drawing_area#misc#realize ();
 
   (* Listening messages *)
   let course = ref None in (* deg *)

sw/ground_segment/cockpit/gcs.ml

@@ -583,7 +583,7 @@ let () =
   let my_alert = new Pages.alert alert_page in
 
   (** Altitude graph frame *)
-  let alt_graph = GMisc.drawing_area () in
+  let alt_graph = new Gtk_tools.pixmap_in_drawin_area () in
 
   (** plugin frame *)
   let plugin_width = 400 and plugin_height = 300 in
@@ -594,7 +594,7 @@ let () =
 		 "aircraft", ac_notebook#coerce;
 		 "editor", editor_frame#coerce;
 		 "alarms", alert_page#coerce;
-		 "altgraph", alt_graph#coerce (*alt_frame#coerce*);
+		 "altgraph", alt_graph#drawing_area#coerce (*alt_frame#coerce*);
 	   "plugin", plugin_frame#coerce] in
 
   let the_layout = ExtXml.child layout "0" in

sw/ground_segment/cockpit/live.ml

@@ -835,15 +835,16 @@ let rotate_and_translate = fun l angle dx dy ->
   ) l) dx dy
 let flip = fun l -> List.map (fun (x, y) -> (-x, y)) l
 
-let draw_altgraph = fun (da:GMisc.drawing_area) (geomap:MapCanvas.widget) aircrafts ->
+let draw_altgraph = fun (da_object:Gtk_tools.pixmap_in_drawin_area) (geomap:MapCanvas.widget) aircrafts ->
   (** First estimate the coverage of the window *)
   let width_c, height_c = Gdk.Drawable.get_size geomap#canvas#misc#window in
   let (xc0, yc0) = geomap#canvas#get_scroll_offsets in
   let (east, _y0) = geomap#window_to_world (float xc0) (float (yc0+height_c))
   and (west, _y1) = geomap#window_to_world (float (xc0+width_c)) (float yc0) in
 
+  let da = da_object#drawing_area in
   let width, height = Gdk.Drawable.get_size da#misc#window in
-  let dr = GDraw.pixmap ~width ~height ~window:da () in
+  let dr = da_object#get_pixmap () in
   dr#set_background `BLACK;
   dr#set_foreground `BLACK;
 

sw/ground_segment/cockpit/live.mli

@@ -70,7 +70,7 @@ val safe_bind : string -> (string -> Pprz.values -> unit) -> unit
 val track_size : int ref
 (** Default length for A/C tracks on the 2D view *)
 
-val listen_acs_and_msgs : MapCanvas.widget -> GPack.notebook -> Pages.alert -> bool -> GMisc.drawing_area -> unit
+val listen_acs_and_msgs : MapCanvas.widget -> GPack.notebook -> Pages.alert -> bool -> Gtk_tools.pixmap_in_drawin_area -> unit
 (** [listen_acs_and_msgs geomap aircraft_notebook alert_page auto_center_new_ac] *)
 
 val jump_to_block : string -> int -> unit

sw/ground_segment/cockpit/pages.ml

@@ -1,26 +1,26 @@
 (*
-* $Id$
+ * $Id$
-*
+ *
-* Copyright (C) 2006 ENAC, Pierre-Sélim Huard, Pascal Brisset, Antoine Drouin
+ * Copyright (C) 2006 ENAC, Pierre-Sélim Huard, Pascal Brisset, Antoine Drouin
-*
+ *
-* This file is part of paparazzi.
+ * This file is part of paparazzi.
-*
+ *
-* paparazzi is free software; you can redistribute it and/or modify
+ * paparazzi is free software; you can redistribute it and/or modify
-* it under the terms of the GNU General Public License as published by
+ * it under the terms of the GNU General Public License as published by
-* the Free Software Foundation; either version 2, or (at your option)
+ * the Free Software Foundation; either version 2, or (at your option)
-* any later version.
+ * any later version.
-*
+ *
-* paparazzi is distributed in the hope that it will be useful,
+ * paparazzi is distributed in the hope that it will be useful,
-* but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
-* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-* GNU General Public License for more details.
+ * GNU General Public License for more details.
-*
+ *
-* You should have received a copy of the GNU General Public License
+ * You should have received a copy of the GNU General Public License
-* along with paparazzi; see the file COPYING.  If not, write to
+ * along with paparazzi; see the file COPYING.  If not, write to
-* the Free Software Foundation, 59 Temple Place - Suite 330,
+ * the Free Software Foundation, 59 Temple Place - Suite 330,
-* Boston, MA 02111-1307, USA. 
+ * Boston, MA 02111-1307, USA. 
-*
+ *
-*)
+ *)
 
 (*****************************************************************************)
 (* Information pages such as alert, infrared, gps, artificial horizon        *)
@@ -34,10 +34,10 @@ open Printf
 (** alert page *)
 class alert (widget: GBin.frame) =
   let scrolled = GBin.scrolled_window 
-    ~hpolicy: `AUTOMATIC 
+      ~hpolicy: `AUTOMATIC 
-    ~vpolicy: `AUTOMATIC  
+      ~vpolicy: `AUTOMATIC  
-    ~packing: widget#add
+      ~packing: widget#add
-    () 
+      () 
   in
   let view = GText.view ~editable:false ~packing: scrolled#add () in
 (* the object itselft *)
@@ -57,23 +57,23 @@ class alert (widget: GBin.frame) =
 	
 	last <- text
       end
- end
+  end
 
 (*****************************************************************************)
 (* infrared page                                                             *)
 (*****************************************************************************)
 class infrared (widget: GBin.frame) =
   let table = GPack.table
-    ~rows: 4
+      ~rows: 4
-    ~columns: 2
+      ~columns: 2
-    ~row_spacings: 5
+      ~row_spacings: 5
-    ~col_spacings: 5
+      ~col_spacings: 5
-    ~packing: widget#add
+      ~packing: widget#add
-    ()
+      ()
   in
   let contrast_status = 
     GMisc.label ~text: "" ~packing: (table#attach ~top:0 ~left: 1) ()
-      in
+  in
   let contrast_value = 
     GMisc.label ~text: "" ~packing: (table#attach ~top:1 ~left: 1) ()
   in
@@ -89,24 +89,24 @@ class infrared (widget: GBin.frame) =
     ignore (GMisc.label ~text: "gps hybrid mode" ~packing: (table#attach ~top:2 ~left: 0) ());
     ignore (GMisc.label ~text: "gps hybrid factor" ~packing: (table#attach ~top:3 ~left: 0) ())
   in
-object
+  object
-  val parent = widget
+    val parent = widget
-  val table = table
+    val table = table
 
-  val contrast_status = contrast_status
+    val contrast_status = contrast_status
-  val contrast_value = contrast_value
+    val contrast_value = contrast_value
-  val gps_hybrid_mode = gps_hybrid_mode
+    val gps_hybrid_mode = gps_hybrid_mode
-  val gps_hybrid_factor = gps_hybrid_factor
+    val gps_hybrid_factor = gps_hybrid_factor
 
-  method set_contrast_status (s:string) = 
+    method set_contrast_status (s:string) = 
-    contrast_status#set_label s
+      contrast_status#set_label s
-  method set_contrast_value (s:int) =
+    method set_contrast_value (s:int) =
-    contrast_value#set_label (Printf.sprintf "%d" s)
+      contrast_value#set_label (Printf.sprintf "%d" s)
-  method set_gps_hybrid_mode (s:string) = 
+    method set_gps_hybrid_mode (s:string) = 
-    gps_hybrid_mode#set_label s
+      gps_hybrid_mode#set_label s
-  method set_gps_hybrid_factor (s:float) =
+    method set_gps_hybrid_factor (s:float) =
-    gps_hybrid_factor#set_label (Printf.sprintf "%.8f" s)
+      gps_hybrid_factor#set_label (Printf.sprintf "%.8f" s)
-end
+  end
 
 (*****************************************************************************)
 (* gps page                                                                  *)
@@ -115,7 +115,8 @@ class gps ?(visible = fun _ -> true) (widget: GBin.frame) =
   let vbox = GPack.vbox ~packing:widget#add () in
 
   let sw = GBin.scrolled_window ~hpolicy:`AUTOMATIC ~vpolicy:`AUTOMATIC ~packing:vbox#add () in
-  let da = GMisc.drawing_area ~show:true ~packing:sw#add_with_viewport () in
+
+  let da_object = new Gtk_tools.pixmap_in_drawin_area ~packing:sw#add_with_viewport () in
 
   (* Reset buttons *)
   let hbox = GPack.hbox ~packing:vbox#pack ~show:false () in
@@ -124,70 +125,71 @@ class gps ?(visible = fun _ -> true) (widget: GBin.frame) =
   let warm = GButton.button ~label:"Warmstart" ~packing:hbox#add () in
   let cold = GButton.button ~label:"Coldstart" ~packing:hbox#add () in
 
-object
+  object
-  val mutable active_cno = []
+    val mutable active_cno = []
-  val mutable active_flags = []
+    val mutable active_flags = []
 
-  method connect_reset = fun (callback:int -> unit) ->
+    method connect_reset = fun (callback:int -> unit) ->
-    hbox#misc#show ();
+      hbox#misc#show ();
-    ignore (hot#connect#clicked (fun () -> callback 0));
+      ignore (hot#connect#clicked (fun () -> callback 0));
-    ignore (warm#connect#clicked (fun () -> callback 1));
+      ignore (warm#connect#clicked (fun () -> callback 1));
-    ignore (cold#connect#clicked (fun () -> callback 2))
+      ignore (cold#connect#clicked (fun () -> callback 2))
 
-  method svsinfo pacc a =
+    method svsinfo pacc a =
-    if visible widget then
+      if visible widget then
-      let {Gtk.width=width; height=height} = da#misc#allocation in
+	let da = da_object#drawing_area in
-      
+	let {Gtk.width=width; height=height} = da#misc#allocation in
-      (* Background *)
+	
-      let dr = GDraw.pixmap ~width ~height ~window:da () in
+	(* Background *)
-      dr#set_foreground (`NAME "white");
+	let dr = da_object#get_pixmap () in
-      dr#rectangle ~x:0 ~y:0 ~width ~height ~filled:true ();
+	dr#set_foreground (`NAME "white");
-      
+	dr#rectangle ~x:0 ~y:0 ~width ~height ~filled:true ();
-      let context = da#misc#create_pango_context in
+	
-      context#set_font_by_name ("sans " ^ string_of_int 10);
+	let context = da#misc#create_pango_context in
-      let layout = context#create_layout in
+	context#set_font_by_name ("sans " ^ string_of_int 10);
-      
+	let layout = context#create_layout in
-      let n = Array.length a in
+	
-      let sep_size = 3 in
+	let n = Array.length a in
-      let indic_size = min 25 ((width-(n+1)*sep_size)/n) in
+	let sep_size = 3 in
-      let max_cn0 = 50 in
+	let indic_size = min 25 ((width-(n+1)*sep_size)/n) in
+	let max_cn0 = 50 in
 
-      Pango.Layout.set_text layout "Dummy";
+	Pango.Layout.set_text layout "Dummy";
-      let (_, h) = Pango.Layout.get_pixel_size layout in
+	let (_, h) = Pango.Layout.get_pixel_size layout in
 
-      let size = fun cn0 -> (max 20 cn0 - 20) * 2 in
+	let size = fun cn0 -> (max 20 cn0 - 20) * 2 in
 
-      let y = sep_size + h + (size max_cn0) in
+	let y = sep_size + h + (size max_cn0) in
-      for i = 0 to n - 1 do
+	for i = 0 to n - 1 do
-	let (id, cn0, flags, age) = a.(i) in
+	  let (id, cn0, flags, age) = a.(i) in
-	if age < 60 then
+	  if age < 60 then
-	  let x = sep_size + i * (sep_size+indic_size) in
+	    let x = sep_size + i * (sep_size+indic_size) in
-	  
+	    
-	  (* level *)
+	    (* level *)
-	  Pango.Layout.set_text layout (sprintf "% 2d" cn0);
+	    Pango.Layout.set_text layout (sprintf "% 2d" cn0);
-	  dr#put_layout ~x ~y:0 ~fore:`BLACK layout;
+	    dr#put_layout ~x ~y:0 ~fore:`BLACK layout;
-	  
+	    
-	  (* bar *)
+	    (* bar *)
-	  let color = if age > 5 then "grey" else if flags land 0x01 = 1 then "green" else "red" in
+	    let color = if age > 5 then "grey" else if flags land 0x01 = 1 then "green" else "red" in
-	  dr#set_foreground (`NAME color);
+	    dr#set_foreground (`NAME color);
-	  let height = size cn0 in
+	    let height = size cn0 in
-	  dr#rectangle ~filled:true ~x ~y:(y-height) ~width:indic_size ~height ();
+	    dr#rectangle ~filled:true ~x ~y:(y-height) ~width:indic_size ~height ();
-	  (* SV id *)
+	    (* SV id *)
-	  Pango.Layout.set_text layout (sprintf "% 2d" id);
+	    Pango.Layout.set_text layout (sprintf "% 2d" id);
-	  dr#put_layout ~x ~y ~fore:`BLACK layout
+	    dr#put_layout ~x ~y ~fore:`BLACK layout
-      done;
+	done;
 
-      (* Pacc *)
+	(* Pacc *)
-      let max_pacc = 2000 in
+	let max_pacc = 2000 in
-      dr#set_foreground (`NAME "red");
+	dr#set_foreground (`NAME "red");
-      let w = min width ((pacc*width)/max_pacc) in
+	let w = min width ((pacc*width)/max_pacc) in
-      dr#rectangle ~filled:true ~x:0 ~y:(y+h) ~width:w ~height:h ();
+	dr#rectangle ~filled:true ~x:0 ~y:(y+h) ~width:w ~height:h ();
-      Pango.Layout.set_text layout (if pacc = 0 then "Pos accuracy: N/A" else sprintf "Pos accuracy: %.1fm" (float pacc/.100.));
+	Pango.Layout.set_text layout (if pacc = 0 then "Pos accuracy: N/A" else sprintf "Pos accuracy: %.1fm" (float pacc/.100.));
-      let (_, h) = Pango.Layout.get_pixel_size layout in
+	let (_, h) = Pango.Layout.get_pixel_size layout in
-      dr#put_layout ~x:((width-w)/2) ~y:(y+h) ~fore:`BLACK layout;
+	dr#put_layout ~x:((width-w)/2) ~y:(y+h) ~fore:`BLACK layout;
-      
+	
-      (new GDraw.drawable da#misc#window)#put_pixmap ~x:0 ~y:0 dr#pixmap
+	(new GDraw.drawable da#misc#window)#put_pixmap ~x:0 ~y:0 dr#pixmap
-end
+  end
 
 (*****************************************************************************)
 (* Misc page                                                                 *)
@@ -201,7 +203,7 @@ let index_of = fun label ->
       failwith (sprintf "Unknown label in Misc.index_of: %s" label)
   in
   search 0
-  
+    
 class misc ~packing (widget: GBin.frame) =
   let rows = Array.length misc_fields in
   let table = GPack.table ~rows ~columns:2 ~row_spacings:5 ~col_spacings:40 ~packing () in
@@ -232,11 +234,11 @@ let rc_setting_index = function
 
 let rc_mode_index = function
     "AUTO1" -> 0 | "AUTO2" -> 1
-  | x -> -1
+  | _x -> -1
 
 let rc_setting_mode_index = function
     "UP" -> 0 | "DOWN" -> 1
-  | x -> -1
+  | _x -> -1
 
 let one_rc_mode = fun (table:GPack.table) rc_mode ->
   let i = rc_mode_index (ExtXml.attrib rc_mode "name") in
@@ -245,9 +247,9 @@ let one_rc_mode = fun (table:GPack.table) rc_mode ->
     and text = ExtXml.attrib rc_setting "var" in
     let (j, k) = rc_setting_index name in
     ignore (GMisc.label ~text ~packing:(table#attach ~top:(1+2*j+k) ~left:(1+2*i)) ())
-    )
+	    )
     (Xml.children rc_mode)
-  
+    
 
 class rc_settings = fun ?(visible = fun _ -> true) xmls ->
   let sw = GBin.scrolled_window ~hpolicy:`AUTOMATIC ~vpolicy:`AUTOMATIC () in
@@ -283,13 +285,13 @@ class rc_settings = fun ?(visible = fun _ -> true) xmls ->
     method widget = sw#coerce
     method set = fun v1 v2 ->
       if visible self#widget then
-	  let i = rc_mode_index rc_mode 
+	let i = rc_mode_index rc_mode 
-	  and j = rc_setting_mode_index rc_setting_mode in
+	and j = rc_setting_mode_index rc_setting_mode in
-	  if i >= 0 && j >= 0 then
+	if i >= 0 && j >= 0 then
-	    let s1 = string_of_float v1 in
+	  let s1 = string_of_float v1 in
-	    let s2 = string_of_float v2 in
+	  let s2 = string_of_float v2 in
-	    
+	  
-	    values.(i).(j).(0)#set_text s1;
+	  values.(i).(j).(0)#set_text s1;
-	    values.(i).(j).(1)#set_text s2
+	  values.(i).(j).(1)#set_text s2
   end
 

sw/ground_segment/cockpit/strip.ml

@@ -78,6 +78,7 @@ let set_color labels name color =
 
 class gauge = fun (gauge_da:GMisc.drawing_area) ->
   object (self)
+    inherit Gtk_tools.pixmap_in_drawin_area ~drawing_area:gauge_da ()
     method layout = fun string ->
       let context = gauge_da#misc#create_pango_context in
       let layout = context#create_layout in
@@ -101,7 +102,7 @@ class vgauge = fun ?(color="green") ?(history_len=50) gauge_da v_min v_max ->
     method set = fun ?arrow ?(background="orange") value strings ->
       let {Gtk.width=width; height=height} = gauge_da#misc#allocation in
       if height > 1 then (* Else the drawing area is not allocated already *)
-	let dr = GDraw.pixmap ~width ~height ~window:gauge_da () in
+	let dr = self#get_pixmap () in
 	dr#set_foreground (`NAME background);
 	dr#rectangle ~x:0 ~y:0 ~width ~height ~filled:true ();
 	
@@ -169,7 +170,7 @@ class hgauge = fun ?(color="green") gauge_da v_min v_max ->
     method set = fun ?(background="orange") value string ->
       let {Gtk.width=width; height=height} = gauge_da#misc#allocation in
       if height > 1 then (* Else the drawing area is not allocated already *)
-	let dr = GDraw.pixmap ~width ~height ~window:gauge_da () in
+	let dr = self#get_pixmap () in
 	dr#set_foreground (`NAME background);
 	dr#rectangle ~x:0 ~y:0 ~width ~height ~filled:true ();
 	

sw/lib/ocaml/gtk_tools.ml

@@ -27,8 +27,12 @@
 (** GTK utilities
  *)
 
-class pixmap_in_drawin_area = fun ~width ~height ~packing () -> 
+class pixmap_in_drawin_area = fun ?drawing_area ?width ?height ?packing () -> 
-  let da = GMisc.drawing_area ~width ~height ~show:true ~packing () in
+  let da =
+    match drawing_area with
+      None ->
+	GMisc.drawing_area ?width ?height ~show:true ?packing ()
+    | Some d -> d in
   object
     val mutable pixmap = None
 

sw/lib/ocaml/gtk_tools.mli

@@ -26,11 +26,13 @@
 (** GTK utilities
  *)
 
-(** Allocate a drawing area and filling pixmap on request *)
+(** Allocate a drawing area and filling pixmap on request.
+    if ~drawing_area is provided, width, heigh and packing are ignored *)
 class pixmap_in_drawin_area : 
-    width:int ->
+    ?drawing_area:GMisc.drawing_area ->
-    height:int ->
+    ?width:int ->
-    packing:(GObj.widget -> unit) ->
+    ?height:int ->
+    ?packing:(GObj.widget -> unit) ->
     unit ->
       object
 	method drawing_area : GMisc.drawing_area

sw/logalizer/Makefile

@@ -43,7 +43,7 @@ plotter : plotter.cmo
 
 plot : log_file.cmx gtk_export.cmx export.cmx plot.cmx
 	@echo OL $@
-	$(Q)$(OCAMLOPT) $(INCLUDES) -o $@ unix.cmxa str.cmxa xml-light.cmxa glibivy-ocaml.cmxa lablgtk.cmxa lib-pprz.cmxa lablglade.cmxa gtkInit.cmx  $^
+	$(Q)$(OCAMLOPT) $(INCLUDES) -o $@ unix.cmxa str.cmxa xml-light.cmxa glibivy-ocaml.cmxa lablgtk.cmxa lib-pprz.cmxa xlib-pprz.cmxa lablglade.cmxa gtkInit.cmx  $^
 
 sd2log : sd2log.cmo
 	@echo OL $@

sw/logalizer/plot.ml

@@ -80,7 +80,6 @@ let labelled_entry = fun ?width_chars text value (h:GPack.box) ->
   label, GEdit.entry ?width_chars ~text:value ~packing:h#pack ()
 
 class plot = fun ~width ~height ~packing () ->
-  let da = GMisc.drawing_area ~width ~height ~show:true ~packing () in
   let curves = Hashtbl.create 3 in
   object (self)
     val mutable min_x = max_float
@@ -92,6 +91,7 @@ class plot = fun ~width ~height ~packing () ->
     val mutable csts = ([] : float list)
     val mutable auto_scale = true
 
+    inherit Gtk_tools.pixmap_in_drawin_area ~width ~height ~packing ()
 
     method private update_scale = fun values ->
       let n = Array.length values in
@@ -136,8 +136,6 @@ class plot = fun ~width ~height ~packing () ->
 
     method destroy = fun () -> ()
 
-    method drawing_area = da
-
     method add_cst = fun v ->
       csts <- v :: csts;
       self#redraw ()
@@ -164,8 +162,9 @@ class plot = fun ~width ~height ~packing () ->
       self#redraw ()
 
     method redraw = fun () ->
+      let da = self#drawing_area in
       let {Gtk.width=width; height=height} = da#misc#allocation in
-      let dr = GDraw.pixmap ~width ~height ~window:da () in
+      let dr = self#get_pixmap () in
       dr#set_foreground (`NAME "white");
       dr#rectangle ~x:0 ~y:0 ~width ~height ~filled:true ();
 
@@ -252,7 +251,7 @@ class plot = fun ~width ~height ~packing () ->
       (* Actually draw *)
       (new GDraw.drawable da#misc#window)#put_pixmap ~x:0 ~y:0 dr#pixmap
 
-    initializer(ignore (da#event#connect#expose ~callback:(fun _ -> self#redraw (); false)))
+    initializer(ignore (self#drawing_area#event#connect#expose ~callback:(fun _ -> self#redraw (); false)))
   end