Thank you for the answer ! Now, I have another problem. The little 
obecjts move but soooooo slowly. I tried to tell them "stepAt: 50." but 
it doesn't make a difference. What should I do ?

And, to avoid some more question, is there a good place to find 
extensive tutorials/manuals about Morphic ?

stF

Karl Ramberg wrote:

>Stefan Champailler wrote:
>  
>
>>Dear you all,
>>
>>I have made a small program taht creates a PasteUpMorph and puts some
>>RectangleMorph inside. It works perfectly. Now I want to animate the
>>rectangle a bit. Therefore I've constructed some code to update the
>>Rectangle's position. Unfortunately, I have to bring the focus on the
>>PasteUpMorph  to see the rectangles move. So basically, what I need is a
>>way to "refresh" the PasteUpMorph each time I change the rectangle's
>>position. Or, I simply just miss a philosphical point here.
>>
>>    
>>
>Easiest way to this is to make use of the morphic stepping.
>Like: 
>RectangleMorph>>step
>		    self position: (self position + (3 at 0))
>
>
>This adds the rectangle and it movements to the world cycle and update 
>should be automatic.
>
>
>  
>