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|
-----------------------------------------------------------------------
-- GtkAda - Ada95 binding for the Gimp Toolkit --
-- --
-- Copyright (C) 2000-2003 --
-- Emmanuel Briot, Joel Brobecker and Arnaud Charlet --
-- --
-- This library 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 of the License, or (at your option) any later version. --
-- --
-- This library 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 this library; if not, write to the --
-- Free Software Foundation, Inc., 59 Temple Place - Suite 330, --
-- Boston, MA 02111-1307, USA. --
-- --
-----------------------------------------------------------------------
with Ada.Text_IO; use Ada.Text_IO;
with Glib; use Glib;
with Glib.Error; use Glib.Error;
with Gdk.Event; use Gdk.Event;
with Gdk.Rgb; use Gdk.Rgb;
with Gtk.Arguments; use Gtk.Arguments;
with Gtk.Drawing_Area; use Gtk.Drawing_Area;
with Gtk.Handlers; use Gtk.Handlers;
with Gdk.Pixbuf; use Gdk.Pixbuf;
with Gtk.Style; use Gtk.Style;
with Gtk.Widget; use Gtk.Widget;
package body Power_GNU is
Default_Width : constant := 800;
Default_Height : constant := 600;
------------------------
-- Callbacks packages --
------------------------
package Event_Cb is new Gtk.Handlers.Return_Callback
(Image_Drawing_Record, Boolean);
package Destroy_Cb is new Gtk.Handlers.Callback
(Image_Drawing_Record);
package Image_Callback is new Gtk.Handlers.Callback
(Image_Drawing_Record);
------------------------
-- Internal Callbacks --
------------------------
procedure Destroy (Draw : access Image_Drawing_Record'Class);
procedure Size_Request
(Draw : access Image_Drawing_Record'Class;
Args : Gtk_Args);
procedure Size_Allocate
(Draw : access Image_Drawing_Record'Class;
Args : Gtk_Args);
function Expose
(Draw : access Image_Drawing_Record'Class;
Event : Gdk_Event) return Boolean;
-------------
-- Destroy --
-------------
procedure Destroy (Draw : access Image_Drawing_Record'Class) is
begin
if Draw.Orig = Null_Pixbuf then
return;
end if;
-- Destroy the associated image
Unref (Draw.Orig);
Unref (Draw.Pix);
end Destroy;
------------
-- Expose --
------------
function Expose
(Draw : access Image_Drawing_Record'Class;
Event : Gdk_Event) return Boolean is
pragma Unreferenced (Event);
begin
if Draw.Pix = Null_Pixbuf then
return False;
end if;
Render_To_Drawable
(Draw.Pix,
Get_Window (Draw),
Gtk.Style.Get_Black_GC (Get_Style (Draw)),
0, 0,
0, 0,
Get_Width (Draw.Pix), Get_Height (Draw.Pix),
Dither_Normal,
0, 0);
return False;
end Expose;
-------------
-- Gtk_New --
-------------
procedure Gtk_New (Draw : out Image_Drawing) is
begin
-- The drawing area MUST be created with Gdk.Rgb colormap,
-- otherwise the image can not be rendered correctly.
Gtk.Widget.Push_Colormap (Gdk.Rgb.Get_Cmap);
Draw := new Image_Drawing_Record;
Power_GNU.Initialize (Draw);
Gtk.Widget.Pop_Colormap;
end Gtk_New;
----------------
-- Initialize --
----------------
procedure Initialize (Draw : access Image_Drawing_Record'Class) is
begin
Gtk.Drawing_Area.Initialize (Draw);
-- Set up the appropriate callbacks to redraw, ...
Event_Cb.Connect
(Draw, "expose_event", Event_Cb.To_Marshaller (Expose'Access), True);
Image_Callback.Connect (Draw, "size_request", Size_Request'Access);
Image_Callback.Connect (Draw, "size_allocate", Size_Allocate'Access);
Destroy_Cb.Connect
(Draw, "destroy",
Destroy_Cb.To_Marshaller (Destroy'Access));
end Initialize;
---------------
-- Set_Image --
---------------
procedure Set_Image
(Draw : Image_Drawing;
Image : String)
is
Error : GError;
begin
if Draw.Orig /= Null_Pixbuf then
Unref (Draw.Orig);
Unref (Draw.Pix);
end if;
Gdk_New_From_File (Draw.Orig, Image, Error);
if Error /= null then
Put_Line ("Error: " & Get_Message (Error));
Error_Free (Error);
return;
end if;
Draw.Pix := Scale_Simple
(Draw.Orig,
Gint (Get_Allocation_Width (Draw)),
Gint (Get_Allocation_Height (Draw)));
Gtk.Widget.Draw (Gtk_Widget (Draw));
end Set_Image;
-------------------
-- Size_Allocate --
-------------------
procedure Size_Allocate
(Draw : access Image_Drawing_Record'Class;
Args : Gtk_Args)
is
Allocation : Gtk_Allocation_Access := To_Allocation (Args, 1);
begin
if Draw.Pix = Null_Pixbuf then
return;
end if;
Unref (Draw.Pix);
Draw.Pix := Scale_Simple
(Draw.Orig,
Gint (Allocation.Width),
Gint (Allocation.Height));
Gtk.Handlers.Emit_Stop_By_Name (Draw, "size_allocate");
end Size_Allocate;
------------------
-- Size_Request --
------------------
procedure Size_Request
(Draw : access Image_Drawing_Record'Class;
Args : Gtk_Args)
is
Requisition : Gtk_Requisition_Access := To_Requisition (Args, 1);
begin
Requisition.Width := Default_Width;
Requisition.Height := Default_Height;
-- Stop the signal from being propagated to the parent's default
-- size_request function
Gtk.Handlers.Emit_Stop_By_Name (Draw, "size_request");
end Size_Request;
end Power_GNU;
|
