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NAME="AEN2928"
>scribble-simple.c</A
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CLASS="PROGRAMLISTING"
> /* 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 <stdlib.h>
#include <gtk/gtk.h>
/* Backing pixmap for drawing area */
static GdkPixmap *pixmap = NULL;
/* Create a new backing pixmap of the appropriate size */
static gboolean 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 gboolean expose_event( GtkWidget *widget,
GdkEventExpose *event )
{
gdk_draw_drawable (widget->window,
widget->style->fg_gc[gtk_widget_get_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 */
static void draw_brush( GtkWidget *widget,
gdouble x,
gdouble y)
{
GdkRectangle update_rect;
update_rect.x = x - 5;
update_rect.y = y - 5;
update_rect.width = 10;
update_rect.height = 10;
gdk_draw_rectangle (pixmap,
widget->style->black_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 gboolean button_press_event( GtkWidget *widget,
GdkEventButton *event )
{
if (event->button == 1 && pixmap != NULL)
draw_brush (widget, event->x, event->y);
return TRUE;
}
static gboolean motion_notify_event( GtkWidget *widget,
GdkEventMotion *event )
{
int x, y;
GdkModifierType state;
if (event->is_hint)
gdk_window_get_pointer (event->window, &x, &y, &state);
else
{
x = event->x;
y = event->y;
state = event->state;
}
if (state & GDK_BUTTON1_MASK && pixmap != NULL)
draw_brush (widget, x, y);
return TRUE;
}
void quit ()
{
exit (0);
}
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 (window, "destroy",
G_CALLBACK (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 (drawing_area, "expose_event",
G_CALLBACK (expose_event), NULL);
g_signal_connect (drawing_area, "configure_event",
G_CALLBACK (configure_event), NULL);
/* Event signals */
g_signal_connect (drawing_area, "motion_notify_event",
G_CALLBACK (motion_notify_event), NULL);
g_signal_connect (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);
/* .. And a quit button */
button = gtk_button_new_with_label ("Quit");
gtk_box_pack_start (GTK_BOX (vbox), button, FALSE, FALSE, 0);
g_signal_connect_swapped (button, "clicked",
G_CALLBACK (gtk_widget_destroy),
window);
gtk_widget_show (button);
gtk_widget_show (window);
gtk_main ();
return 0;
}</PRE
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>scribble-xinput.c</A
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><TD
><PRE
CLASS="PROGRAMLISTING"
> /* 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 <gtk/gtk.h>
/* Backing pixmap for drawing area */
static GdkPixmap *pixmap = NULL;
/* Create a new backing pixmap of the appropriate size */
static gboolean
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 gboolean
expose_event (GtkWidget *widget, GdkEventExpose *event)
{
gdk_draw_drawable (widget->window,
widget->style->fg_gc[gtk_widget_get_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_get_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_get_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 gboolean
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 gboolean
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 (inputd, "destroy",
G_CALLBACK (input_dialog_destroy), (gpointer) &inputd);
g_signal_connect_swapped (GTK_INPUT_DIALOG (inputd)->close_button,
"clicked",
G_CALLBACK (gtk_widget_hide),
inputd);
gtk_widget_hide (GTK_INPUT_DIALOG (inputd)->save_button);
gtk_widget_show (inputd);
}
else
{
if (!gtk_widget_get_mapped (inputd))
gtk_widget_show (inputd);
else
gdk_window_raise (inputd->window);
}
}
void
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 (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 (drawing_area, "expose_event",
G_CALLBACK (expose_event), NULL);
g_signal_connect (drawing_area, "configure_event",
G_CALLBACK (configure_event), NULL);
/* Event signals */
g_signal_connect (drawing_area, "motion_notify_event",
G_CALLBACK (motion_notify_event), NULL);
g_signal_connect (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 (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 (button, "clicked",
G_CALLBACK (gtk_widget_destroy),
window);
gtk_widget_show (button);
gtk_widget_show (window);
gtk_main ();
return 0;
}</PRE
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