Thank you folks for your help. Here in attachment you'll find two
compressed files, one with the Eclipse project (use File->Import) and
another with the plain java files.

Don't try to find much logic in it, it is a very stripped down version
of another simulation, just for illustration.

Thank you once more,

Luís

On 7 August 2012 23:33, Sean Luke <[log in to unmask]> wrote:
> field.remove(foo) will definitely remove foo from the field, and the Field Portrayal will definitely stop calling draw() on its corresponding SimplePortrayal.  So if you're having a problem at this point either there's a bug in your code or a bug in ours.  To determine this, I will need you to send me (directly) a tarball containing an ideally simple example of the bug happening, including source code, so we can poke around.
>
> The only other thing I can think of is that you are using the same SimplePortrayal for multiple objects in the field -- that's typical -- but are storing some kind of state or information in the SimplePortrayal which is somehow carrying over -- that's unlikely.  Or you have the object being added to the field somehow or it's part of some other field which is being drawn.
>
> Sean
>