/* Copyright 2007 Openismus GmbH
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <clutter/clutter.h>
#include <stdlib.h>

ClutterActor *rect = NULL;

/* This must return a value between 0 and 1.0.
 * This will be called as many times per seconds as specified in our call to 
 * clutter_timeline_new().
 */
gdouble
on_alpha (ClutterAlpha *alpha, gpointer data)
{
  /* Get the position in the timeline, 
   *  so we can base our value upon it:
   */
  ClutterTimeline *timeline = clutter_alpha_get_timeline (alpha);
  return clutter_timeline_get_progress (timeline);
}


int main(int argc, char *argv[])
{
  ClutterColor stage_color = { 0x00, 0x00, 0x00, 0xff };
  ClutterColor rect_color = { 0xff, 0xff, 0xff, 0x99 };

  clutter_init (&argc, &argv);

  /* Get the stage and set its size and color: */
  ClutterActor *stage = clutter_stage_get_default ();
  clutter_actor_set_size (stage, 200, 200);
  clutter_stage_set_color (CLUTTER_STAGE (stage), &stage_color);

  /* Add a rectangle to the stage: */
  rect = clutter_rectangle_new_with_color (&rect_color);
  clutter_actor_set_size (rect, 40, 40);
  clutter_actor_set_position (rect, 10, 10);
  clutter_container_add_actor (CLUTTER_CONTAINER (stage), rect);
  clutter_actor_show (rect);

  /* Show the stage: */
  clutter_actor_show (stage);

  ClutterTimeline *timeline = clutter_timeline_new(5000 /* milliseconds */);
  clutter_timeline_set_loop(timeline, TRUE); 
  clutter_timeline_start(timeline);

  /* Instead of our custom callback, 
   * we could use a standard callback. For instance, CLUTTER_ALPHA_SINE_INC. 
   */
  ClutterAlpha *alpha = clutter_alpha_new_with_func (timeline, &on_alpha, NULL, NULL);

  ClutterKnot knot[2];
  knot[0].x = 10;
  knot[0].y = 10;
  knot[1].x= 150;
  knot[1].y= 150;
 
  ClutterBehaviour *behaviour = clutter_behaviour_path_new_with_knots (alpha, knot, sizeof(knot) / sizeof(ClutterKnot));
  clutter_behaviour_apply (behaviour, rect);
  g_object_unref (timeline);

  /* Start the main loop, so we can respond to events: */
  clutter_main ();

  return EXIT_SUCCESS;

}