Re: [Boost-users] BGL Fruchterman Reingold Layout

From: Douglas Gregor (doug.gregor_at_[hidden])
Date: 2005-04-17 18:55:19

On Dec 16, 2004, at 11:05 AM, Gordon Smith wrote:

> I searched the net, but couldn't see any real world examples of what 
> the
> Fruchterman Reingold Layout should look like.  Having played with it, 
> it
> seems the vertices gravitate towards the bounding rectangle and a 
> horizontal
> / Vertical cross about one fifth into the rectangle.  Is this expected
> (which is not very impressive)?
>
> I have attached two small images one of a regular spring layout and 
> one of
> the Fruchterman Reingold Layout (note the data is just random).

I've *finally* found this bug. I had completely misread the formulation 
of the "grid variant" of the Fruchterman-Reingold, and, consequently, 
the grid_force_pairs implementation was bogus. I've reimplemented 
grid_force_pairs and it should be correct now. I've verified it with a 
few randomly-generated graphs in our viewer and things are looking a 
LOT better.

Thanks again for reporting this bug (now several months old), and sorry 
about the rather ludicrous delay :) The updated code is in CVS, of 
course.

        Doug