gnome_canvas_item_i2w (item, &x, &y);
gnome_canvas_w2c_d (GNOME_CANVAS(item->canvas), x, y, &c, &d);
printf ("item bounds now (%g,%g),(%g,%g)\n", a, b, c, d);
gnome_canvas_item_i2w (item, &x, &y);
gnome_canvas_w2c_d (GNOME_CANVAS(item->canvas), x, y, &c, &d);
printf ("item bounds now (%g,%g),(%g,%g)\n", a, b, c, d);