Re: Gets rid of unnecessary logic in beam.cc. (issue4449065)

[address@hidden]

On Apr 28, 2011, at 11:37, address@hidden wrote:

> Reviewers: ,
> 
> Message:
> If I understand it correctly, Han-Wen's original collision code in
> beam.cc was treating intervals as if is_empty checked if they were
> uninitialized or invalid in some way, whereas in fact, is_empty gets rid
> of anything where left is greater than right.  However, the LEFT and
> RIGHT values of intervals in collision_free contain y values for the
> beam position, and thus, the left one will invariably be higher than the
> right one if the beam has a negative slope.  Thus, is_empty was (I
> think) ruling out any solution with a negative slope.
> 
> I'm not sure if this is too drastic to address issue 1613 (there may
> need to be some error checking fit in), but I think that it more or less
> fixes the problem.
> 

I just ran the regtests - it seems this causes other problems in certain 
circumstances - it was too drastic. That said, I think the general idea of the 
approach (rethinking the use of is_empty) is valid.

Cheers,
MS