Perhaps not quite as fancy as a Quadtree but about 20x faster when having
10k elements for lists is the attached CS. It uses a simple, specialized
version of TransformMorph which makes a few assumptions about the layout of
the children (e.g., being vertically arranged) and uses binary subdivision
in drawing. It's basically the same effect as with the Quadtree version (it
just doesn't have to deal with the nastyness of updating the tree etc.)

Cheers,
  - Andreas

> -----Original Message-----
> From: squeak-dev-bounces at lists.squeakfoundation.org 
> [mailto:squeak-dev-bounces at lists.squeakfoundation.org] On 
> Behalf Of Tim Rowledge
> Sent: Tuesday, July 22, 2003 1:58 AM
> To: squeak-dev at lists.squeakfoundation.org
> Subject: Re: [GOODIE] Fun with QuadTrees
> 
> 
> "Eddie Cottongim" <cottonsqueak at earthlink.net> wrote:
> 
> > I decided to teach myself about this data structure and see 
> if it could be
> > used to help ScrollPanes with very large numbers of objects 
> scroll more
> > smoothly.
> This is definitely the sort of work I like to see getting 
> done. What is
> the performance impact on more 'realistic' lists - ie those found in
> system browsers or the BFAV?
> 
> tim
> --
> Tim Rowledge, tim at sumeru.stanford.edu, http://sumeru.stanford.edu/tim
> The value of a program is proportional to the weight of its output.
> 
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