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/*
Copyright (C) 2009 Paul Davis
This program 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 program 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 program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "cairo_widget.h"
#include "gui_thread.h"
CairoWidget::CairoWidget ()
: _width (1),
_height (1),
_dirty (true),
_pixmap (0)
{
}
CairoWidget::~CairoWidget ()
{
if (_pixmap) {
gdk_pixmap_unref (_pixmap);
}
}
bool
CairoWidget::on_expose_event (GdkEventExpose *event)
{
Gdk::Rectangle const exposure (
event->area.x, event->area.y, event->area.width, event->area.height
);
Gdk::Rectangle r = exposure;
Gdk::Rectangle content (0, 0, _width, _height);
bool intersects;
r.intersect (content, intersects);
if (intersects) {
GdkDrawable* drawable = get_window()->gobj ();
if (_dirty) {
if (_pixmap) {
gdk_pixmap_unref (_pixmap);
}
_pixmap = gdk_pixmap_new (drawable, _width, _height, -1);
cairo_t* cr = gdk_cairo_create (_pixmap);
render (cr);
cairo_destroy (cr);
_dirty = false;
}
gdk_draw_drawable (
drawable,
get_style()->get_fg_gc (Gtk::STATE_NORMAL)->gobj(),
_pixmap,
r.get_x(),
r.get_y(),
r.get_x(),
r.get_y(),
r.get_width(),
r.get_height()
);
}
return true;
}
/** Marks the widget as dirty, so that render () will be called on
* the next GTK expose event.
*/
void
CairoWidget::set_dirty ()
{
ENSURE_GUI_THREAD (mem_fun (*this, &CairoWidget::set_dirty));
_dirty = true;
queue_draw ();
}
/** Handle a size allocation.
* @param alloc GTK allocation.
*/
void
CairoWidget::on_size_allocate (Gtk::Allocation& alloc)
{
Gtk::EventBox::on_size_allocate (alloc);
_width = alloc.get_width ();
_height = alloc.get_height ();
set_dirty ();
}
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