Re: 1 expose/configure event function for ALL pixmaps or for EACH??
- From: Chris Seberino <seberino spawar navy mil>
- To: Paul Davis <pbd op net>
- Cc: gtk-list gnome org
- Subject: Re: 1 expose/configure event function for ALL pixmaps or for EACH??
- Date: Wed, 30 Jan 2002 08:18:51 -0800
Paul
Thanks again for reply. I was thinking hard about what
you said and looking at scribble.c in the GTK+ tutorial
which has expose & configure event functions like mine.
(See below)
Q1: So if I have 10 pixmaps lets say, then when
I resize window, GTK+ will call configure_event
function 10 times? The first argument will be
the address of the next pixmap for 10 calls?
So to draw DIFFERENT things in a pixmap I must
put code in configure_event like this?
if (first_argument == pixmap_pointerX) {
drawing code for pixmapX
Do this for X = 0, 1, 2, ... 9 ???
Q2: It looks like expose_event won't change if
1 - 10,000 pixmaps but configure_event will right?
Thanks,
Chris
/* example-start scribble-simple scribble-simple.c */
/* 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 gint configure_event( GtkWidget *widget,
GdkEventConfigure *event )
{
if (pixmap)
gdk_pixmap_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_pixmap(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 */
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_draw (widget, &update_rect);
}
static gint button_press_event( GtkWidget *widget,
GdkEventButton *event )
{
if (event->button == 1 && pixmap != NULL)
draw_brush (widget, event->x, event->y);
return TRUE;
}
static gint 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 ()
{
gtk_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);
gtk_signal_connect (GTK_OBJECT (window), "destroy",
GTK_SIGNAL_FUNC (quit), NULL);
/* Create the drawing area */
drawing_area = gtk_drawing_area_new ();
gtk_drawing_area_size (GTK_DRAWING_AREA (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 */
gtk_signal_connect (GTK_OBJECT (drawing_area), "expose_event",
(GtkSignalFunc) expose_event, NULL);
gtk_signal_connect (GTK_OBJECT(drawing_area),"configure_event",
(GtkSignalFunc) configure_event, NULL);
/* Event signals */
gtk_signal_connect (GTK_OBJECT (drawing_area), "motion_notify_event",
(GtkSignalFunc) motion_notify_event, NULL);
gtk_signal_connect (GTK_OBJECT (drawing_area), "button_press_event",
(GtkSignalFunc) 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);
gtk_signal_connect_object (GTK_OBJECT (button), "clicked",
GTK_SIGNAL_FUNC (gtk_widget_destroy),
GTK_OBJECT (window));
gtk_widget_show (button);
gtk_widget_show (window);
gtk_main ();
return 0;
}
/* example-end */
On Tue, Jan 29, 2002 at 01:29:24PM -0500, Paul Davis wrote:
> >The expose and configure events need to be bound
> >to a function regarding pixmaps.
> >
> >Do I make one function for ALL pixmaps or a separate
> >function for EACH???
> >
> >(All pixmaps are on same window.)
>
> use one. the particular GtkWidget (ie. GtkPixmap) that is being
> exposed and/or configured will be passed to the function.
--
=======================================================
| Dr. Christian Seberino || (619) 553-7940 (office) |
| SPAWARSYSCEN 2363 || (619) 553-2836 (fax) |
| 53560 HULL ST || |
| SAN DIEGO CA 92152-5001 || seberino spawar navy mil |
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