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
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
|
/* GTK - The GIMP Toolkit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library 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.
*/
#include <config.h>
#include <gtk/gtk.h>
/* Backing pixmap for drawing area */
static GdkPixmap *pixmap = NULL;
/* Create a new backing pixmap of the appropriate size */
static gint
configure_event (GtkWidget *widget, GdkEventConfigure *event)
{
if (pixmap)
g_object_unref (pixmap);
pixmap = gdk_pixmap_new (widget->window,
widget->allocation.width,
widget->allocation.height,
-1);
gdk_draw_rectangle (pixmap,
widget->style->white_gc,
TRUE,
0, 0,
widget->allocation.width,
widget->allocation.height);
return TRUE;
}
/* Redraw the screen from the backing pixmap */
static gint
expose_event (GtkWidget *widget, GdkEventExpose *event)
{
gdk_draw_drawable (widget->window,
widget->style->fg_gc[GTK_WIDGET_STATE (widget)],
pixmap,
event->area.x, event->area.y,
event->area.x, event->area.y,
event->area.width, event->area.height);
return FALSE;
}
/* Draw a rectangle on the screen, size depending on pressure,
and color on the type of device */
static void
draw_brush (GtkWidget *widget, GdkInputSource source,
gdouble x, gdouble y, gdouble pressure)
{
GdkGC *gc;
GdkRectangle update_rect;
switch (source)
{
case GDK_SOURCE_MOUSE:
gc = widget->style->dark_gc[GTK_WIDGET_STATE (widget)];
break;
case GDK_SOURCE_PEN:
gc = widget->style->black_gc;
break;
case GDK_SOURCE_ERASER:
gc = widget->style->white_gc;
break;
default:
gc = widget->style->light_gc[GTK_WIDGET_STATE (widget)];
}
update_rect.x = x - 10 * pressure;
update_rect.y = y - 10 * pressure;
update_rect.width = 20 * pressure;
update_rect.height = 20 * pressure;
gdk_draw_rectangle (pixmap, gc, TRUE,
update_rect.x, update_rect.y,
update_rect.width, update_rect.height);
gtk_widget_queue_draw_area (widget,
update_rect.x, update_rect.y,
update_rect.width, update_rect.height);
}
static void
print_button_press (GdkDevice *device)
{
g_print ("Button press on device '%s'\n", device->name);
}
static gint
button_press_event (GtkWidget *widget, GdkEventButton *event)
{
print_button_press (event->device);
if (event->button == 1 && pixmap != NULL) {
gdouble pressure;
gdk_event_get_axis ((GdkEvent *)event, GDK_AXIS_PRESSURE, &pressure);
draw_brush (widget, event->device->source, event->x, event->y, pressure);
}
return TRUE;
}
static gint
motion_notify_event (GtkWidget *widget, GdkEventMotion *event)
{
gdouble x, y;
gdouble pressure;
GdkModifierType state;
if (event->is_hint)
{
gdk_device_get_state (event->device, event->window, NULL, &state);
gdk_event_get_axis ((GdkEvent *)event, GDK_AXIS_X, &x);
gdk_event_get_axis ((GdkEvent *)event, GDK_AXIS_Y, &y);
gdk_event_get_axis ((GdkEvent *)event, GDK_AXIS_PRESSURE, &pressure);
}
else
{
x = event->x;
y = event->y;
gdk_event_get_axis ((GdkEvent *)event, GDK_AXIS_PRESSURE, &pressure);
state = event->state;
}
if (state & GDK_BUTTON1_MASK && pixmap != NULL)
draw_brush (widget, event->device->source, x, y, pressure);
return TRUE;
}
void
input_dialog_destroy (GtkWidget *w, gpointer data)
{
*((GtkWidget **)data) = NULL;
}
void
create_input_dialog ()
{
static GtkWidget *inputd = NULL;
if (!inputd)
{
inputd = gtk_input_dialog_new();
g_signal_connect (G_OBJECT (inputd), "destroy",
G_CALLBACK (input_dialog_destroy), (gpointer) &inputd);
g_signal_connect_swapped (G_OBJECT (GTK_INPUT_DIALOG (inputd)->close_button),
"clicked",
G_CALLBACK (gtk_widget_hide),
G_OBJECT (inputd));
gtk_widget_hide (GTK_INPUT_DIALOG (inputd)->save_button);
gtk_widget_show (inputd);
}
else
{
if (!GTK_WIDGET_MAPPED (inputd))
gtk_widget_show (inputd);
else
gdk_window_raise (inputd->window);
}
}
int
main (int argc, char *argv[])
{
GtkWidget *window;
GtkWidget *drawing_area;
GtkWidget *vbox;
GtkWidget *button;
gtk_init (&argc, &argv);
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_widget_set_name (window, "Test Input");
vbox = gtk_vbox_new (FALSE, 0);
gtk_container_add (GTK_CONTAINER (window), vbox);
gtk_widget_show (vbox);
g_signal_connect (G_OBJECT (window), "destroy",
G_CALLBACK (gtk_main_quit), NULL);
/* Create the drawing area */
drawing_area = gtk_drawing_area_new ();
gtk_widget_set_size_request (GTK_WIDGET (drawing_area), 200, 200);
gtk_box_pack_start (GTK_BOX (vbox), drawing_area, TRUE, TRUE, 0);
gtk_widget_show (drawing_area);
/* Signals used to handle backing pixmap */
g_signal_connect (G_OBJECT (drawing_area), "expose_event",
G_CALLBACK (expose_event), NULL);
g_signal_connect (G_OBJECT(drawing_area),"configure_event",
G_CALLBACK (configure_event), NULL);
/* Event signals */
g_signal_connect (G_OBJECT (drawing_area), "motion_notify_event",
G_CALLBACK (motion_notify_event), NULL);
g_signal_connect (G_OBJECT (drawing_area), "button_press_event",
G_CALLBACK (button_press_event), NULL);
gtk_widget_set_events (drawing_area, GDK_EXPOSURE_MASK
| GDK_LEAVE_NOTIFY_MASK
| GDK_BUTTON_PRESS_MASK
| GDK_POINTER_MOTION_MASK
| GDK_POINTER_MOTION_HINT_MASK);
/* The following call enables tracking and processing of extension
events for the drawing area */
gtk_widget_set_extension_events (drawing_area, GDK_EXTENSION_EVENTS_CURSOR);
/* .. And some buttons */
button = gtk_button_new_with_label ("Input Dialog");
gtk_box_pack_start (GTK_BOX (vbox), button, FALSE, FALSE, 0);
g_signal_connect (G_OBJECT (button), "clicked",
G_CALLBACK (create_input_dialog), NULL);
gtk_widget_show (button);
button = gtk_button_new_with_label ("Quit");
gtk_box_pack_start (GTK_BOX (vbox), button, FALSE, FALSE, 0);
g_signal_connect_swapped (G_OBJECT (button), "clicked",
G_CALLBACK (gtk_widget_destroy),
G_OBJECT (window));
gtk_widget_show (button);
gtk_widget_show (window);
gtk_main ();
return 0;
}
|
