Re: [boost] GGL Review

Subject: Re: [boost] GGL Review
From: Phil Endecott (spam_from_boost_dev_at_[hidden])
Date: 2009-11-17 12:23:38

Jonathan Franklin wrote:
> On Tue, Nov 17, 2009 at 6:35 AM, Brandon Kohn <blkohn_at_[hidden]> wrote:
>> My own view
>> is that something that only works part of the time really doesn't work.
>
> I'm sure that's great for whatever you do.  It is valid in many use cases.
>
> The visualization software that I work on, on the other hand, prefers
> speed over making sure that point p1 is provably inside or outside the
> box.  If it's *that* close, then it doesn't matter.

Hi Jonathan,

Do please have a look at the paper that I linked to before, and in 
particular the figure at the top of the second page:

   http://www.mpi-inf.mpg.de/~kettner/pub/nonrobust_cgta_06.pdf

Two points:

1. Failures may not occur only in cases when things are very close.  A 
problematic input may cause the output to be grossly wrong.

2. You may not get a wrong answer; the program might instead segfault 
or loop forever.

Regards,  Phil.