Well, for instance to change the settings of all the objects that have been created, or to get some settings of some fields of them. I suppose the getOneIntersectingObject method somehow has to find the active objects first, then calculate where they all are, find one that intersects, and then pass a reference to that object. It would be interesting to know how to find the active objects (and get references to them), and to find out how that method does it. Cheers, Karl

I believe there is a way to download the source of the greenfoot package. Go to the 'Download' page; on the lower right, there is a link to the 'Source code' for the Greenfoot IDE.

We're both guessing, but I don't think that's really going to help. akkekalle, you can get all objects in the world by using the getObjects() method (from the World class), with a null parameter. It returns a list. For example: List allObjects = getWorld().getObjects(null); You would then generally use a 'for' loop to go through all the objects and do something with them: To answer your question: It certainly could work that way, but that would be inefficient and is not how it actually works. Greenfoot has a a sophisticated collision-checking algorithm which I won't explain in detail here, but basically it involves dividing the world into smaller and smaller areas so that you can discard most actors from the search immediately (without checking each one in turn to see if it intersects). If you were really interested in the details, you could download the source code as danpost suggests, but I suspect you would have trouble understanding it at this stage.

I think he means a simpler access.