[ltk-user] problems with create-text

[Andre RsFiveTwo]

Hi,
I'm trying to create an animation with words based on the (ltktest) function
in the library (rotate).
For that I'm storing the words in a plist. The code to maintain the words
is:

(defvar *initial-word-energy* 100)
(defvar *words* '()) ; list of words in the form (:text :x :y :energy)

(defun make-word (text x y display-item)
  (list :text text :x x :y y :display-item display-item :energy
*initial-word-energy*))

(defun add-word (word) (push word *words*))


Then I created a button that will add words to the plist and to the canvas:

           (enter-text-button (make-instance 'button
                                             :master controls
                                             :text "Enter text"
                                             :command (lambda ()
                                                        ;;store word in
*words*
                                                        (let*  ((text (text
user-text-entry))
                                                                (x (random
(read-from-string

(cget drawing-canvas-reference

                 :width))))
                                                                (y (random
(read-from-string

(cget drawing-canvas-reference

                 :height))))
                                                                ;;put text
in canvas

(display-item (create-text drawing-canvas-reference

               x

               y

               text))
                                                                (word
(make-word
                                                                       text
                                                                       x
                                                                       y

display-item)))

                                                          ;;store new word
                                                          (add-word word)

                                                          ;;clear entry
widget
                                                          (setf (text
user-text-entry) "")
                                                          (focus
user-text-entry)

(finish-output)))))


The idea is that a word will store the position, the text, other things and
the visual representation of the text.

In the animation part (same code as rotate in the library) I move the words,
and here is the problem.
If I try the move changing the coordinates of the updated values of x and y
of the word the text apearing in the canvas 'jumps' in the first move,
afterward it move normally.
The other alternative is to use itemmove, which works. but I would like to
just manipulate x and y of the word and transpose it to the created text
item in the canvas.

     ;;move display item
    [do not work] ---> (set-coords *drawing-canvas-reference* (getf word
:display-item) (list (getf word :x) (getf word :y)))
    [works]         ----> (itemmove *drawing-canvas-reference* (getf word
:display-item) atract-x atract-y)

So, I would like to understand better why there seems to be a difference in
the values of x an y for the element stored and the element displayed,
although they have been created with the same values.
If possible, I would like to know how can I query the created text element
about it's x and y values.

Sorry for the long message.
Any help is appreciated.
Thanks,
André
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