CGAL users discussion list

["sinan mutlu" <>]

Hi again,

I thing that if we give the point coordinates in integer, it calculates the straight skeleton faster compare to using floating point coordinates.
Is there a way to accelerate the calculation by using floating point coordinates.

Thank you for your time and consideration.

Sinan Mutlu

From: Andreas Fabri <>

To:

Subject: Re: [cgal-discuss] Straight_Skeleton

Date: Wed, 12 Mar 2008 13:42:25 +0100

References: <>

User-agent: Thunderbird 2.0.0.12 (Windows/20080213)

Hi Sinan,

This exception is an internal thing and it gets catched internally.
It happens in predicates that first try to get evaluated with floating
point arithmetic, and if the outcome is uncertain (that is we cannot
trust it), the exception is thrown, catched and the predicate is
computed again, this time with an arbitrary precision arithmetic.

andreas


sinan mutlu wrote:

Hi,

I am trying to find "straight skeletons" of some polygons. But sometimes it gets too much time to calculate a concave polygon and while trying to
compute the straight skeleton, it gives the following message:

"First-chance exception at 0x7c812a5b (kernel32.dll) in Example.exe: Microsoft C++ exception: CGAL::Uncertain_conversion_exception at memory location 0x00108100..."

I have not understood the reason why it takes so much time to calculate it.

Can anybody help to understand the reason.

Best Regards.

Sinan Mutlu