We have a problem where we need to draw areas on a map that only slightly 
overlap.  This is used in a routing application, where events are assigned to 
the assigned user for each area. What we want is to have the areas overlap 
slightly, so as to avoid any possibility of there being a gap.

For us to have a small area along the border between two areas in which which 
user the event is assigned to is acceptable. For us to have even the smallest 
area in which an event might fall between the cracks is not. Given my 
understanding of floating point rounding errors, it's not possible to have 
absolute equality. If you're going to avoid any cracks, you're going to have to 
have some overlap.

What we're envisioning is to have a newly drawn area clip against the existing 
area, and then to expand the newly drawn area slightly.

We're considering the JTS Topology Suite. It looks as if its Buffer 
functionality might do what we need. But before we install it and try to work 
with it, we have a few questions:


1.       When I create a buffer around a polygon or multipolygon, does the 
geometry that it returns contain the buffer plus the polygon, or just the 
buffer?

2.       If the returned geometry contains just the buffer, will a union of the 
buffer with the original polygon never contain holes along the boundary, due to 
floating point rounding errors?


[KorTerra Logo_small_jpg]<http://www.korterra.com/>

[cid:[email protected]]


Jeffrey C. Dege
Senior Programmer/Analyst

phone     952.697.3148
fax          952.697.3141
email      [email protected]
website   www.korterra.com<http://www.korterra.com/>

[cid:[email protected]]<http://www.facebook.com/KorTerraInc#!/KorTerraInc?fref=ts>
 [cid:[email protected]] <http://twitter.com/KorTerraInc>  
[cid:[email protected]] 
<http://www.linkedin.com/company/korterra-inc.>  
[cid:[email protected]] <http://www.youtube.com/user/KorTerraInc>  
[google-plus] 
<https://plus.google.com/114258183299577608534#114258183299577608534/posts>  
[rss] <http://www.korterra.com/rss>



------------------------------------------------------------------------------
_______________________________________________
Jts-topo-suite-user mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/jts-topo-suite-user

Reply via email to