/* 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;
static GdkGC *draw_gc;
/* Create a new backing pixmap of the appropriate size */
static gint configure_event( GtkWidget *widget,
GdkEventConfigure *event )
{
if (pixmap)
g_object_unref (pixmap);
if (draw_gc)
g_object_unref (draw_gc);
/* 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;
static GdkGC *draw_gc;
/* Create a new backing pixmap of the appropriate size */
static gint configure_event( GtkWidget *widget,
GdkEventConfigure *event )
{
if (pixmap)
g_object_unref (pixmap);
if (draw_gc)
g_object_unref (draw_gc);
pixmap = gdk_pixmap_new (widget->window,
widget->allocation.width,
widget->allocation.height,
-1);
draw_gc = gdk_gc_new (widget->window);
gdk_gc_copy (draw_gc, widget->style->black_gc);
gdk_gc_set_function(draw_gc, GDK_INVERT);
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 */
static void draw_brush( GtkWidget *widget,
gdouble x,
gdouble y)
{
GdkRectangle update_rect;
update_rect.x = x - 15;
update_rect.y = y - 15;
update_rect.width = 30;
update_rect.height = 30;
gdk_draw_rectangle (pixmap,
draw_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 gint button_press_event( GtkWidget *widget,
GdkEventButton *event )
{
if (event->button == 1 && pixmap != NULL)
draw_brush (widget, event->x, event->y);
return TRUE;
}
Я тоже к такому мнению пришёл.
но чёто не совсем понимаю как ето реализовать технически.
так что если не затруднит, плиз екзампл
PS. Я новичок в графике на Gtk/Gdk