Geometry Boost List: [ggl] Re: Problems with the difference between two polygons

Subject: [ggl] Re: Problems with the difference between two polygons
From: Barend Gehrels (barend)
Date: 2011-08-08 10:24:08

Hi Angus,

On 7-8-2011 13:34, Angus Johnson wrote:
> On 7/08/2011 8:05 PM, Barend Gehrels wrote:
>> Why should you do that? Round them and then consider them as 
>> duplicate? If they would be duplicate (before rounding), they would 
>> not be included (since this is solved).
>
> Hi Barend.
> Yes, of course you're right that fractional differences certainly 
> aren't duplicates. I'm sorry I implied otherwise.
> Having swapped over some time ago to using integers in my Clipper 
> library, and now being so used to scaling fractional coordinates into 
> integers to manage precision, I'd made the presumption that fractional 
> values in these specific tests was unnecessary precision. I now accept 
> that some might consider otherwise. Also, I can see now that some of 
> my comments may have seemed critical of Ggl and Gtl, and for that I 
> apologize. I really do believe each library has it's strengths and 
> weaknesses. 

OK, thanks. It is good to exchange experiences.

Regards, Barend