File: create_preview_gray.adb

package info (click to toggle)
libgtkada2 2.8.1-6lenny3
  • links: PTS, VCS
  • area: main
  • in suites: lenny
  • size: 13,496 kB
  • ctags: 3,886
  • sloc: ada: 103,189; ansic: 45,411; perl: 5,500; sh: 2,812; makefile: 1,169; xml: 19
file content (148 lines) | stat: -rw-r--r-- 5,156 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
-----------------------------------------------------------------------
--          GtkAda - Ada95 binding for the Gimp Toolkit              --
--                                                                   --
--                     Copyright (C) 1998-1999                       --
--        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.                                       --
--                                                                   --
-- As a special exception, if other files instantiate generics from  --
-- this unit, or you link this unit with other files to produce an   --
-- executable, this  unit  does not  by itself cause  the resulting  --
-- executable to be covered by the GNU General Public License. This  --
-- exception does not however invalidate any other reasons why the   --
-- executable file  might be covered by the  GNU Public License.     --
-----------------------------------------------------------------------

with Glib; use Glib;
with Gtk.Box;    use Gtk.Box;
with Gtk.Enums; use Gtk.Enums;
with Glib.Main; use Glib.Main;
with Gtk.Preview; use Gtk.Preview;
with Gtk.Widget; use Gtk.Widget;
with Gtk.Window; use Gtk.Window;
with Gtk; use Gtk;
with Common; use Common;

package body Create_Preview_Gray is

   package Preview_Idle is new Glib.Main.Generic_Sources (Gtk_Preview);

   Window : aliased Gtk.Window.Gtk_Window;

   Gray_Idle : G_Source_Id := 0;
   Count     : Guchar := 1;

   ----------
   -- Help --
   ----------

   function Help return String is
   begin
      return "The @bGtk_Preview@B widget displays an RGB image, which can be"
        & " easily manipulated through an array of @bGuchar@Bs. The image"
        & " can be either color or grayscale.";
   end Help;

   --------------------
   -- Gray_Idle_Func --
   --------------------

   function Gray_Idle_Func (Preview : Gtk_Preview) return Boolean is
      Buf : Guchar_Array (0 .. 255);
   begin
      for I in 0 .. Guchar'(255) loop
         for J in 0 .. (255) loop
            Buf (J) := I + Guchar (J) + Count;
         end loop;
         Draw_Row (Preview, Buf, 0, Gint (I), 256);
      end loop;
      Count := Count + 1;
      Draw (Preview);
      return True;
   end Gray_Idle_Func;

   ---------------------
   -- Preview_Destroy --
   ---------------------

   procedure Preview_Destroy (Dummy  : access Gtk_Widget_Record'Class) is
      pragma Warnings (Off, Dummy);
   begin
      if Gray_Idle > 0 then
         Remove (Gray_Idle);
         Gray_Idle := 0;
      end if;
      Window := null;
   end Preview_Destroy;

   ------------------
   -- Demo_Destroy --
   ------------------

   procedure Demo_Destroy (Dummy : access Gtk_Widget_Record'Class) is
   begin
      if Window /= null then
         Destroy (Window);
         Preview_Destroy (Dummy);
      end if;
   end Demo_Destroy;

   ---------
   -- Run --
   ---------

   procedure Run (Frame : access Gtk.Frame.Gtk_Frame_Record'Class) is
      Preview : Gtk_Preview;
      Box     : Gtk_Box;

   begin
      if Window = null then

         --  Create a dummy widget, that will tell us whenever the user
         --  selected a new demo (since the children of Frame are automatically
         --  deleted in that case). We can then close the dialog.

         Gtk_New_Vbox (Box, Homogeneous => False);
         Add (Frame, Box);
         Widget_Handler.Connect
           (Box, "destroy",
            Widget_Handler.To_Marshaller (Demo_Destroy'Access));

         --  Now create the real demo

         Gtk_New (Window, Window_Toplevel);
         Widget_Handler.Connect
           (Window, "destroy",
            Widget_Handler.To_Marshaller (Preview_Destroy'Access));
         Set_Title (Window, "test");
         Set_Border_Width (Window, Border_Width => 10);

         Gtk_New (Preview, Preview_Grayscale);
         Size (Preview, 256, 256);
         Add (Window, Preview);
         Show (Preview);

         Gray_Idle := Preview_Idle.Idle_Add (Gray_Idle_Func'Access, Preview);
         Show (Window);
      else
         Destroy (Window);
      end if;

   end Run;

end Create_Preview_Gray;