source: trunk/third/libgnomecanvas/libgnomecanvas/gnome-canvas-polygon.c @ 20821

/*
 * Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation
 * All rights reserved.
 *
 * This file is part of the Gnome Library.
 *
 * The Gnome 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.
 *
 * The Gnome 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 the Gnome Library; see the file COPYING.LIB.  If not,
 * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */
/*
  @NOTATION@
 */
/* Polygon item type for GnomeCanvas widget
 *
 * GnomeCanvas is basically a port of the Tk toolkit's most excellent canvas widget.  Tk is
 * copyrighted by the Regents of the University of California, Sun Microsystems, and other parties.
 *
 * Author: Federico Mena <federico@nuclecu.unam.mx>
 *         Rusty Conover <rconover@bangtail.net>
 */

#include <config.h>
#include <math.h>
#include <string.h>
#include "libart_lgpl/art_vpath.h"
#include "libart_lgpl/art_svp.h"
#include "libart_lgpl/art_svp_vpath.h"
#include "libart_lgpl/art_svp_vpath_stroke.h"
#include "libgnomecanvas.h"

#include "gnome-canvas-shape.h"


#define NUM_STATIC_POINTS 256   /* Number of static points to use to avoid allocating arrays */


enum {
        PROP_0,
        PROP_POINTS
};


static void gnome_canvas_polygon_class_init (GnomeCanvasPolygonClass *class);
static void gnome_canvas_polygon_init       (GnomeCanvasPolygon      *poly);
static void gnome_canvas_polygon_destroy    (GtkObject               *object);
static void gnome_canvas_polygon_set_property (GObject              *object,
                                               guint                 param_id,
                                               const GValue         *value,
                                               GParamSpec           *pspec);
static void gnome_canvas_polygon_get_property (GObject              *object,
                                               guint                 param_id,
                                               GValue               *value,
                                               GParamSpec           *pspec);

static void gnome_canvas_polygon_update      (GnomeCanvasItem *item, double *affine, ArtSVP *clip_path, int flags);

static GnomeCanvasItemClass *parent_class;

GType
gnome_canvas_polygon_get_type (void)
{
        static GType polygon_type;

        if (!polygon_type) {
                static const GTypeInfo object_info = {
                        sizeof (GnomeCanvasPolygonClass),
                        (GBaseInitFunc) NULL,
                        (GBaseFinalizeFunc) NULL,
                        (GClassInitFunc) gnome_canvas_polygon_class_init,
                        (GClassFinalizeFunc) NULL,
                        NULL,                   /* class_data */
                        sizeof (GnomeCanvasPolygon),
                        0,                      /* n_preallocs */
                        (GInstanceInitFunc) gnome_canvas_polygon_init,
                        NULL                    /* value_table */
                };

                polygon_type = g_type_register_static (GNOME_TYPE_CANVAS_SHAPE, "GnomeCanvasPolygon",
                                                       &object_info, 0);
        }

        return polygon_type;
}

static void
gnome_canvas_polygon_class_init (GnomeCanvasPolygonClass *class)
{
        GObjectClass *gobject_class;
        GtkObjectClass *object_class;
        GnomeCanvasItemClass *item_class;

        gobject_class = (GObjectClass *) class;
        object_class = (GtkObjectClass *) class;
        item_class = (GnomeCanvasItemClass *) class;

        parent_class = g_type_class_peek_parent (class);

        gobject_class->set_property = gnome_canvas_polygon_set_property;
        gobject_class->get_property = gnome_canvas_polygon_get_property;

        g_object_class_install_property
                (gobject_class,
                 PROP_POINTS,
                 g_param_spec_boxed ("points", NULL, NULL,
                                     GNOME_TYPE_CANVAS_POINTS,
                                     (G_PARAM_READABLE | G_PARAM_WRITABLE)));

        object_class->destroy = gnome_canvas_polygon_destroy;

        item_class->update = gnome_canvas_polygon_update;
}

static void
gnome_canvas_polygon_init (GnomeCanvasPolygon *poly)
{
        poly->path_def = NULL;
}

static void
gnome_canvas_polygon_destroy (GtkObject *object)
{
        GnomeCanvasPolygon *poly;

        g_return_if_fail (object != NULL);
        g_return_if_fail (GNOME_IS_CANVAS_POLYGON (object));

        poly = GNOME_CANVAS_POLYGON (object);

        /* remember, destroy can be run multiple times! */

        if(poly->path_def)
                gnome_canvas_path_def_unref(poly->path_def);

        poly->path_def = NULL;


        if (GTK_OBJECT_CLASS (parent_class)->destroy)
                (* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
}

static void
set_points (GnomeCanvasPolygon *poly, GnomeCanvasPoints *points)
{
        int i;


        if (poly->path_def)
                gnome_canvas_path_def_unref(poly->path_def);

        if (!points) {
                poly->path_def = gnome_canvas_path_def_new();
                gnome_canvas_shape_set_path_def (GNOME_CANVAS_SHAPE (poly), poly->path_def);
                return;
        }


        /* Optomize the path def to the number of points */
        poly->path_def = gnome_canvas_path_def_new_sized(points->num_points+1);

#if 0
        /* No need for explicit duplicate, as closepaths does it for us (Lauris) */
        /* See if we need to duplicate the first point */
        duplicate = ((points->coords[0] != points->coords[2 * points->num_points - 2])
                     || (points->coords[1] != points->coords[2 * points->num_points - 1]));
#endif

        
        gnome_canvas_path_def_moveto (poly->path_def, points->coords[0], points->coords[1]);
        
        for (i = 1; i < points->num_points; i++) {
                gnome_canvas_path_def_lineto(poly->path_def, points->coords[i * 2], points->coords[(i * 2) + 1]);
        }

        gnome_canvas_path_def_closepath (poly->path_def);

        gnome_canvas_shape_set_path_def (GNOME_CANVAS_SHAPE (poly), poly->path_def);
}


static void
gnome_canvas_polygon_set_property (GObject              *object,
                                   guint                 param_id,
                                   const GValue         *value,
                                   GParamSpec           *pspec)
{
        GnomeCanvasItem *item;
        GnomeCanvasPolygon *poly;
        GnomeCanvasPoints *points;

        g_return_if_fail (object != NULL);
        g_return_if_fail (GNOME_IS_CANVAS_POLYGON (object));

        item = GNOME_CANVAS_ITEM (object);
        poly = GNOME_CANVAS_POLYGON (object);

        switch (param_id) {
        case PROP_POINTS:
                points = g_value_get_boxed (value);

                set_points (poly, points);

                gnome_canvas_item_request_update (item);
                break;
        default:
                G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
                break;
        }
}


static void
gnome_canvas_polygon_get_property (GObject              *object,
                                   guint                 param_id,
                                   GValue               *value,
                                   GParamSpec           *pspec)
{
        GnomeCanvasPolygon *poly;

        g_return_if_fail (object != NULL);
        g_return_if_fail (GNOME_IS_CANVAS_POLYGON (object));

        poly = GNOME_CANVAS_POLYGON (object);

        switch (param_id) {
        case PROP_POINTS:
                break;
        default:
                G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
                break;
        }
}


static void
gnome_canvas_polygon_update (GnomeCanvasItem *item, double *affine, ArtSVP *clip_path, int flags)
{
        /* Since the path has already been defined just pass the update up. */

        if (parent_class->update)
                (* parent_class->update) (item, affine, clip_path, flags);
}