path: root/libgnomecanvas/gnome-canvas-polygon.c

/*
 * 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, gdouble *affine, ArtSVP *clip_path, gint flags);

static GnomeCanvasItemClass *parent_class;

GType
gnome_canvas_polygon_get_type (void)
{
    static GType polygon_type;

    if (!polygon_type) {
        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)
{
    gint 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)
{
    g_return_if_fail (object != NULL);
    g_return_if_fail (GNOME_IS_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, gdouble *affine, ArtSVP *clip_path, gint 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);
}