[clutter] Newbie Question re: Scaling & scale_center

[Reuven Wachtfogel]

I want a certain actor to grow by 25% (around the click point) each time I 
click on it.

clutter_actor_animate (..., 
            "scale-x", scale_x * 1.25,
            "scale-y", scale_x * 1.25,
            "fixed::scale-center-x", x,
            "fixed::scale-center-y", y,

The first time I click this works fine. The second time, the actor jumps to a 
different location. The reason for this is that the previous scale-center's 
affect on the location of the actor on the screen is removed. I can think of a 
complicated solution, but is there an easy way to do what I want to do?

Source attached:

Thanks,

rube



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

static gboolean on_group_button_press (ClutterActor *group, ClutterEvent 
*event, gpointer data)
{
  gfloat  x, y;
  gdouble scale_x;

  clutter_event_get_coords (event, &x, &y);
  clutter_actor_transform_stage_point (group, x, y, &x, &y);
  clutter_actor_get_scale (group, &scale_x, NULL);

  clutter_actor_animate (
            group, 
            CLUTTER_LINEAR, 
            1000,
                "scale-x", scale_x * 1.25,
                "scale-y", scale_x * 1.25,
            "fixed::scale-center-x", x,
            "fixed::scale-center-y", y,
            NULL );
  return TRUE; 
}
int main(int argc, char *argv[])
{
  clutter_init (&argc, &argv);

  ClutterColor blue = { 0x00, 0x00, 0x80, 0xff };

  ClutterActor *stage = clutter_stage_get_default ();
  ClutterActor *group = clutter_group_new ();
  ClutterActor *text  = clutter_text_new_full ("Sans 50", "The Quick Brown Fox 
Jumped Over The Lazy Dog", &blue);
  clutter_text_set_line_wrap (CLUTTER_TEXT(text), TRUE);

  clutter_container_add_actor (CLUTTER_CONTAINER (group), text);
  clutter_container_add_actor (CLUTTER_CONTAINER (stage),  group);

  clutter_actor_set_size (text, 400, 400);
  clutter_actor_set_size (stage, 500, 500);

  clutter_actor_show (stage);

  clutter_actor_set_reactive (group, TRUE);
  g_signal_connect (group, "button-press-event", G_CALLBACK 
(on_group_button_press), NULL);

  clutter_main ();

  return (0);
}