Beta Testers for buffering algorithm improvements?

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Beta Testers for buffering algorithm improvements?

Martin Davis
JTS'ers,

As you may have experienced, buffering in JTS currently has some
performance challenges in situations involving large buffer distances.  
I'm excited to say that I've implemented some code enhancements which
*dramatically* improve buffer performance in these cases (as well as
providing an overall improvement).

I've tested this code as extensively as I can, and am pretty confident
that it is robust and accurate.  But it's always good to have other
people beat on it as well!

So, is anyone out there ready, able and willing to test out the new
buffering code?  Ideally this would be someone who has a application
which uses buffering in a significant way, and which allows determining
the performance and correctness characteristics effectively.  I'm
looking for feedback to either confirm that this really is an
improvement, or some test cases which reveal issues if there are any.

If you're able to help out, you can either download and build the
codebase from CVS, or I've built an alpha release of JTS 1.10 which is
available here:

http://tsusiatsoftware.net/jts/files/jts-1.10-alpha.zip

Thanks - Martin

--
Martin Davis
Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022

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Re: Beta Testers for buffering algorithm improvements?

Larry Becker
Congratulations Martin!   Buffering 41 complex aircraft features took 83 seconds with your old algorithm, and only 2 seconds using your new one.  I could find no anomalies.

regards,
Larry Becker

On Wed, Oct 8, 2008 at 4:23 PM, Martin Davis <[hidden email]> wrote:
JTS'ers,

As you may have experienced, buffering in JTS currently has some performance challenges in situations involving large buffer distances.  I'm excited to say that I've implemented some code enhancements which *dramatically* improve buffer performance in these cases (as well as providing an overall improvement).

I've tested this code as extensively as I can, and am pretty confident that it is robust and accurate.  But it's always good to have other people beat on it as well!

So, is anyone out there ready, able and willing to test out the new buffering code?  Ideally this would be someone who has a application which uses buffering in a significant way, and which allows determining the performance and correctness characteristics effectively.  I'm looking for feedback to either confirm that this really is an improvement, or some test cases which reveal issues if there are any.

If you're able to help out, you can either download and build the codebase from CVS, or I've built an alpha release of JTS 1.10 which is available here:

http://tsusiatsoftware.net/jts/files/jts-1.10-alpha.zip

Thanks - Martin

--
Martin Davis
Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022

_______________________________________________
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--
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Re: Beta Testers for buffering algorithm improvements?

Martin Davis
Good to hear, Larry - thanks for testing this.

Larry Becker wrote:

> Congratulations Martin!   Buffering 41 complex aircraft features took
> 83 seconds with your old algorithm, and only 2 seconds using your new
> one.  I could find no anomalies.
>
> regards,
> Larry Becker
>
> On Wed, Oct 8, 2008 at 4:23 PM, Martin Davis <[hidden email]
> <mailto:[hidden email]>> wrote:
>
>     JTS'ers,
>
>     As you may have experienced, buffering in JTS currently has some
>     performance challenges in situations involving large buffer
>     distances.  I'm excited to say that I've implemented some code
>     enhancements which *dramatically* improve buffer performance in
>     these cases (as well as providing an overall improvement).
>
>     I've tested this code as extensively as I can, and am pretty
>     confident that it is robust and accurate.  But it's always good to
>     have other people beat on it as well!
>
>     So, is anyone out there ready, able and willing to test out the
>     new buffering code?  Ideally this would be someone who has a
>     application which uses buffering in a significant way, and which
>     allows determining the performance and correctness characteristics
>     effectively.  I'm looking for feedback to either confirm that this
>     really is an improvement, or some test cases which reveal issues
>     if there are any.
>
>     If you're able to help out, you can either download and build the
>     codebase from CVS, or I've built an alpha release of JTS 1.10
>     which is available here:
>
>     http://tsusiatsoftware.net/jts/files/jts-1.10-alpha.zip
>
>     Thanks - Martin
>
>     --
>     Martin Davis
>     Senior Technical Architect
>     Refractions Research, Inc.
>     (250) 383-3022
>
>     _______________________________________________
>     jts-devel mailing list
>     [hidden email]
>     <mailto:[hidden email]>
>     http://lists.refractions.net/mailman/listinfo/jts-devel
>
>
>
>
> --
> http://amusingprogrammer.blogspot.com/
> ------------------------------------------------------------------------
>
> _______________________________________________
> jts-devel mailing list
> [hidden email]
> http://lists.refractions.net/mailman/listinfo/jts-devel
>  

--
Martin Davis
Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022

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Re: Beta Testers for buffering algorithm improvements?

Martin Davis
In reply to this post by Larry Becker
Larry, a question about your testing.  Were these geometries polygons or
linestrings?  The reason I ask is that I have one optimization
(simplification) which is working for polygons, but not yet for
linestrings.  I'm curious to know whether the speed improvement was due
to all the optimizations, or just one.

Larry Becker wrote:

> Congratulations Martin!   Buffering 41 complex aircraft features took
> 83 seconds with your old algorithm, and only 2 seconds using your new
> one.  I could find no anomalies.
>
> regards,
> Larry Becker
>
> On Wed, Oct 8, 2008 at 4:23 PM, Martin Davis <[hidden email]
> <mailto:[hidden email]>> wrote:
>
>     JTS'ers,
>
>     As you may have experienced, buffering in JTS currently has some
>     performance challenges in situations involving large buffer
>     distances.  I'm excited to say that I've implemented some code
>     enhancements which *dramatically* improve buffer performance in
>     these cases (as well as providing an overall improvement).
>
>     I've tested this code as extensively as I can, and am pretty
>     confident that it is robust and accurate.  But it's always good to
>     have other people beat on it as well!
>
>     So, is anyone out there ready, able and willing to test out the
>     new buffering code?  Ideally this would be someone who has a
>     application which uses buffering in a significant way, and which
>     allows determining the performance and correctness characteristics
>     effectively.  I'm looking for feedback to either confirm that this
>     really is an improvement, or some test cases which reveal issues
>     if there are any.
>
>     If you're able to help out, you can either download and build the
>     codebase from CVS, or I've built an alpha release of JTS 1.10
>     which is available here:
>
>     http://tsusiatsoftware.net/jts/files/jts-1.10-alpha.zip
>
>     Thanks - Martin
>
>     --
>     Martin Davis
>     Senior Technical Architect
>     Refractions Research, Inc.
>     (250) 383-3022
>
>     _______________________________________________
>     jts-devel mailing list
>     [hidden email]
>     <mailto:[hidden email]>
>     http://lists.refractions.net/mailman/listinfo/jts-devel
>
>
>
>
> --
> http://amusingprogrammer.blogspot.com/
> ------------------------------------------------------------------------
>
> _______________________________________________
> jts-devel mailing list
> [hidden email]
> http://lists.refractions.net/mailman/listinfo/jts-devel
>  

--
Martin Davis
Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022

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Re: Beta Testers for buffering algorithm improvements?

Stephen Wong
Hello,

I'd love to test this if there was a GEOS implementation of it... Will it be difficult to port quickly?

Thanks,

Stephen

On Wed, Oct 8, 2008 at 5:22 PM, Martin Davis <[hidden email]> wrote:
Larry, a question about your testing.  Were these geometries polygons or linestrings?  The reason I ask is that I have one optimization (simplification) which is working for polygons, but not yet for linestrings.  I'm curious to know whether the speed improvement was due to all the optimizations, or just one.

Larry Becker wrote:
Congratulations Martin!   Buffering 41 complex aircraft features took 83 seconds with your old algorithm, and only 2 seconds using your new one.  I could find no anomalies.

regards,
Larry Becker

On Wed, Oct 8, 2008 at 4:23 PM, Martin Davis <[hidden email] <mailto:[hidden email]>> wrote:

   JTS'ers,

   As you may have experienced, buffering in JTS currently has some
   performance challenges in situations involving large buffer
   distances.  I'm excited to say that I've implemented some code
   enhancements which *dramatically* improve buffer performance in
   these cases (as well as providing an overall improvement).

   I've tested this code as extensively as I can, and am pretty
   confident that it is robust and accurate.  But it's always good to
   have other people beat on it as well!

   So, is anyone out there ready, able and willing to test out the
   new buffering code?  Ideally this would be someone who has a
   application which uses buffering in a significant way, and which
   allows determining the performance and correctness characteristics
   effectively.  I'm looking for feedback to either confirm that this
   really is an improvement, or some test cases which reveal issues
   if there are any.

   If you're able to help out, you can either download and build the
   codebase from CVS, or I've built an alpha release of JTS 1.10
   which is available here:

   http://tsusiatsoftware.net/jts/files/jts-1.10-alpha.zip

   Thanks - Martin

   --    Martin Davis
   Senior Technical Architect
   Refractions Research, Inc.
   (250) 383-3022

   _______________________________________________
   jts-devel mailing list
   [hidden email]
   <mailto:[hidden email]> ------------------------------------------------------------------------


_______________________________________________
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--
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Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022

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Re: Beta Testers for buffering algorithm improvements?

michaelm-2
In reply to this post by Martin Davis
Hi Martin

I obtained good performance with the new buffer
Here are some extensive tests :

*                            Old buffer   New buffer*
308 polygons - buffer 10  :   4 s   -->   5 s  
308 polygons - buffer 100 :  51 s   -->  10 s
20507 linestrings - b 10  :  23 s   -->  21 s
20507 linestrings - b 10  : 367 s   -->  70 s
6444 points - 10/100/1000 :   3 s   -->   2 s

Performance are constant for point buffer (old, new, small buffers,
large buffers)
Performance do not change much between old and new buffer for small buffers
Performance improve greatly for large buffer (considering Larry's test,
I think the ratio is even higher for larger buffers)

I compared total resulting surfaces with the jump plugin (statistic for
the layer)

For linestring, I did not notice any difference
same area +/- 0.000005 m2 for a total of 2 000 000 000 m2 (let's say the
same)

For polygon, I noticed a small difference
same area +/- 23000 m2 for a total of 5 000 000 000 m2

The image show how the new buffer has simplified the geometry (the old
buffer is marked ith big points, distance between the two buffers are
about 0.3 m for a buffer of 100 m)

Michaël


Martin Davis a écrit :

> Good to hear, Larry - thanks for testing this.
>
> Larry Becker wrote:
>> Congratulations Martin!   Buffering 41 complex aircraft features took
>> 83 seconds with your old algorithm, and only 2 seconds using your new
>> one.  I could find no anomalies.
>>
>> regards,
>> Larry Becker
>>
>> On Wed, Oct 8, 2008 at 4:23 PM, Martin Davis <[hidden email]
>> <mailto:[hidden email]>> wrote:
>>
>>     JTS'ers,
>>
>>     As you may have experienced, buffering in JTS currently has some
>>     performance challenges in situations involving large buffer
>>     distances.  I'm excited to say that I've implemented some code
>>     enhancements which *dramatically* improve buffer performance in
>>     these cases (as well as providing an overall improvement).
>>
>>     I've tested this code as extensively as I can, and am pretty
>>     confident that it is robust and accurate.  But it's always good to
>>     have other people beat on it as well!
>>
>>     So, is anyone out there ready, able and willing to test out the
>>     new buffering code?  Ideally this would be someone who has a
>>     application which uses buffering in a significant way, and which
>>     allows determining the performance and correctness characteristics
>>     effectively.  I'm looking for feedback to either confirm that this
>>     really is an improvement, or some test cases which reveal issues
>>     if there are any.
>>
>>     If you're able to help out, you can either download and build the
>>     codebase from CVS, or I've built an alpha release of JTS 1.10
>>     which is available here:
>>
>>     http://tsusiatsoftware.net/jts/files/jts-1.10-alpha.zip
>>
>>     Thanks - Martin
>>
>>     --     Martin Davis
>>     Senior Technical Architect
>>     Refractions Research, Inc.
>>     (250) 383-3022
>>
>>     _______________________________________________
>>     jts-devel mailing list
>>     [hidden email]
>>     <mailto:[hidden email]>
>>     http://lists.refractions.net/mailman/listinfo/jts-devel
>>
>>
>>
>>
>> --
>> http://amusingprogrammer.blogspot.com/
>> ------------------------------------------------------------------------
>>
>> _______________________________________________
>> jts-devel mailing list
>> [hidden email]
>> http://lists.refractions.net/mailman/listinfo/jts-devel
>>  
>

_______________________________________________
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Re: Beta Testers for buffering algorithm improvements?

Martin Davis
Thanks for the feedback, Michael.

The results for points are expected - there is no change in how point
buffers are computed.

The slight difference in buffer polygon shape between old and new is
expected too - that is a result of the simplification.  The change due
to the simplification should be much less than the error due to the
discretization of the arcs, so should not be considered to be
significant (at least, that's my working hypothesis!).

As for linestrings, in fact the simplification was not enabled for
linestrings in the version I posted (due to some issues with the
algorithm).  I've resolved these, and I've posted a new version of the
library (same URL).  So you might like to retry the linestring test and
see if the results improve.

Martin

Michael Michaud wrote:

> Hi Martin
>
> I obtained good performance with the new buffer
> Here are some extensive tests :
>
> *                            Old buffer   New buffer*
> 308 polygons - buffer 10  :   4 s   -->   5 s  308 polygons - buffer
> 100 :  51 s   -->  10 s
> 20507 linestrings - b 10  :  23 s   -->  21 s
> 20507 linestrings - b 10  : 367 s   -->  70 s
> 6444 points - 10/100/1000 :   3 s   -->   2 s
>
> Performance are constant for point buffer (old, new, small buffers,
> large buffers)
> Performance do not change much between old and new buffer for small
> buffers
> Performance improve greatly for large buffer (considering Larry's
> test, I think the ratio is even higher for larger buffers)
>
> I compared total resulting surfaces with the jump plugin (statistic
> for the layer)
>
> For linestring, I did not notice any difference
> same area +/- 0.000005 m2 for a total of 2 000 000 000 m2 (let's say
> the same)
>
> For polygon, I noticed a small difference
> same area +/- 23000 m2 for a total of 5 000 000 000 m2
>
> The image show how the new buffer has simplified the geometry (the old
> buffer is marked ith big points, distance between the two buffers are
> about 0.3 m for a buffer of 100 m)
>
> Michaël
>
>
> Martin Davis a écrit :
>> Good to hear, Larry - thanks for testing this.
>>
>> Larry Becker wrote:
>>> Congratulations Martin!   Buffering 41 complex aircraft features
>>> took 83 seconds with your old algorithm, and only 2 seconds using
>>> your new one.  I could find no anomalies.
>>>
>>> regards,
>>> Larry Becker
>>>
>>> On Wed, Oct 8, 2008 at 4:23 PM, Martin Davis
>>> <[hidden email] <mailto:[hidden email]>> wrote:
>>>
>>>     JTS'ers,
>>>
>>>     As you may have experienced, buffering in JTS currently has some
>>>     performance challenges in situations involving large buffer
>>>     distances.  I'm excited to say that I've implemented some code
>>>     enhancements which *dramatically* improve buffer performance in
>>>     these cases (as well as providing an overall improvement).
>>>
>>>     I've tested this code as extensively as I can, and am pretty
>>>     confident that it is robust and accurate.  But it's always good to
>>>     have other people beat on it as well!
>>>
>>>     So, is anyone out there ready, able and willing to test out the
>>>     new buffering code?  Ideally this would be someone who has a
>>>     application which uses buffering in a significant way, and which
>>>     allows determining the performance and correctness characteristics
>>>     effectively.  I'm looking for feedback to either confirm that this
>>>     really is an improvement, or some test cases which reveal issues
>>>     if there are any.
>>>
>>>     If you're able to help out, you can either download and build the
>>>     codebase from CVS, or I've built an alpha release of JTS 1.10
>>>     which is available here:
>>>
>>>     http://tsusiatsoftware.net/jts/files/jts-1.10-alpha.zip
>>>
>>>     Thanks - Martin
>>>
>>>     --     Martin Davis
>>>     Senior Technical Architect
>>>     Refractions Research, Inc.
>>>     (250) 383-3022
>>>
>>>     _______________________________________________
>>>     jts-devel mailing list
>>>     [hidden email]
>>>     <mailto:[hidden email]>
>>>     http://lists.refractions.net/mailman/listinfo/jts-devel
>>>
>>>
>>>
>>>
>>> --
>>> http://amusingprogrammer.blogspot.com/
>>> ------------------------------------------------------------------------
>>>
>>>
>>> _______________________________________________
>>> jts-devel mailing list
>>> [hidden email]
>>> http://lists.refractions.net/mailman/listinfo/jts-devel
>>>  
>>
>
>
> ------------------------------------------------------------------------
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> jts-devel mailing list
> [hidden email]
> http://lists.refractions.net/mailman/listinfo/jts-devel
>  

--
Martin Davis
Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022

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Re: Beta Testers for buffering algorithm improvements?

Martin Davis
In reply to this post by Stephen Wong
No, it shouldn't be hard to port the code.  There's not actually too
much code to add - 1 class and a few lines of code in another class.

I was planning to alert the GEOS folks to this development, but I wanted
to wait until I'd fixed the linestring simplification logic, and some
independent testing had been done on JTS.  Both of these have now been
accomplished, so I'll post a notice to the GEOS list.

Stephen Wong wrote:

> Hello,
>
> I'd love to test this if there was a GEOS implementation of it... Will
> it be difficult to port quickly?
>
> Thanks,
>
> Stephen
>
> On Wed, Oct 8, 2008 at 5:22 PM, Martin Davis <[hidden email]
> <mailto:[hidden email]>> wrote:
>
>     Larry, a question about your testing.  Were these geometries
>     polygons or linestrings?  The reason I ask is that I have one
>     optimization (simplification) which is working for polygons, but
>     not yet for linestrings.  I'm curious to know whether the speed
>     improvement was due to all the optimizations, or just one.
>
>     Larry Becker wrote:
>
>         Congratulations Martin!   Buffering 41 complex aircraft
>         features took 83 seconds with your old algorithm, and only 2
>         seconds using your new one.  I could find no anomalies.
>
>         regards,
>         Larry Becker
>
>         On Wed, Oct 8, 2008 at 4:23 PM, Martin Davis
>         <[hidden email] <mailto:[hidden email]>
>         <mailto:[hidden email]
>         <mailto:[hidden email]>>> wrote:
>
>            JTS'ers,
>
>            As you may have experienced, buffering in JTS currently has
>         some
>            performance challenges in situations involving large buffer
>            distances.  I'm excited to say that I've implemented some code
>            enhancements which *dramatically* improve buffer performance in
>            these cases (as well as providing an overall improvement).
>
>            I've tested this code as extensively as I can, and am pretty
>            confident that it is robust and accurate.  But it's always
>         good to
>            have other people beat on it as well!
>
>            So, is anyone out there ready, able and willing to test out the
>            new buffering code?  Ideally this would be someone who has a
>            application which uses buffering in a significant way, and
>         which
>            allows determining the performance and correctness
>         characteristics
>            effectively.  I'm looking for feedback to either confirm
>         that this
>            really is an improvement, or some test cases which reveal
>         issues
>            if there are any.
>
>            If you're able to help out, you can either download and
>         build the
>            codebase from CVS, or I've built an alpha release of JTS 1.10
>            which is available here:
>
>            http://tsusiatsoftware.net/jts/files/jts-1.10-alpha.zip
>
>            Thanks - Martin
>
>            --    Martin Davis
>            Senior Technical Architect
>            Refractions Research, Inc.
>            (250) 383-3022
>
>            _______________________________________________
>            jts-devel mailing list
>            [hidden email]
>         <mailto:[hidden email]>
>            <mailto:[hidden email]
>         <mailto:[hidden email]>>
>
>            http://lists.refractions.net/mailman/listinfo/jts-devel
>
>
>
>
>         --
>         http://amusingprogrammer.blogspot.com/
>         ------------------------------------------------------------------------
>
>
>
>         _______________________________________________
>         jts-devel mailing list
>         [hidden email]
>         <mailto:[hidden email]>
>         http://lists.refractions.net/mailman/listinfo/jts-devel
>          
>
>
>     --
>     Martin Davis
>     Senior Technical Architect
>     Refractions Research, Inc.
>     (250) 383-3022
>
>     _______________________________________________
>     jts-devel mailing list
>     [hidden email]
>     <mailto:[hidden email]>
>     http://lists.refractions.net/mailman/listinfo/jts-devel
>
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> jts-devel mailing list
> [hidden email]
> http://lists.refractions.net/mailman/listinfo/jts-devel
>  

--
Martin Davis
Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022

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Re: Beta Testers for buffering algorithm improvements?

michaelm-2
In reply to this post by Martin Davis
Hi Martin,

I get an error when I try to unzip your new code (and the file is a lot
smaller than the previous one)

> The slight difference in buffer polygon shape between old and new is
> expected too - that is a result of the simplification.  The change due
> to the simplification should be much less than the error due to the
> discretization of the arcs, so should not be considered to be
> significant (at least, that's my working hypothesis!).
Does it mean that if I increase the number of points to represent
rounded arc, the buffer will be more precise everywhere ?
(note that I have no special need for a buffer which has a millimeter
precision when I work whith several km objects)
> As for linestrings, in fact the simplification was not enabled for
> linestrings in the version I posted (due to some issues with the
> algorithm).  I've resolved these, and I've posted a new version of the
> library (same URL).  So you might like to retry the linestring test
> and see if the results improve.
But it's already 5 x faster than with jts-9 ?? (same ration as for
polygons) I'll do the test again as soon as I can

Michaël

>
> Martin
>
> Michael Michaud wrote:
>> Hi Martin
>>
>> I obtained good performance with the new buffer
>> Here are some extensive tests :
>>
>> *                            Old buffer   New buffer*
>> 308 polygons - buffer 10  :   4 s   -->   5 s  308 polygons - buffer
>> 100 :  51 s   -->  10 s
>> 20507 linestrings - b 10  :  23 s   -->  21 s
>> 20507 linestrings - b 10  : 367 s   -->  70 s
>> 6444 points - 10/100/1000 :   3 s   -->   2 s
>>
>> Performance are constant for point buffer (old, new, small buffers,
>> large buffers)
>> Performance do not change much between old and new buffer for small
>> buffers
>> Performance improve greatly for large buffer (considering Larry's
>> test, I think the ratio is even higher for larger buffers)
>>
>> I compared total resulting surfaces with the jump plugin (statistic
>> for the layer)
>>
>> For linestring, I did not notice any difference
>> same area +/- 0.000005 m2 for a total of 2 000 000 000 m2 (let's say
>> the same)
>>
>> For polygon, I noticed a small difference
>> same area +/- 23000 m2 for a total of 5 000 000 000 m2
>>
>> The image show how the new buffer has simplified the geometry (the
>> old buffer is marked ith big points, distance between the two buffers
>> are about 0.3 m for a buffer of 100 m)
>>
>> Michaël
>>
>>
>> Martin Davis a écrit :
>>> Good to hear, Larry - thanks for testing this.
>>>
>>> Larry Becker wrote:
>>>> Congratulations Martin!   Buffering 41 complex aircraft features
>>>> took 83 seconds with your old algorithm, and only 2 seconds using
>>>> your new one.  I could find no anomalies.
>>>>
>>>> regards,
>>>> Larry Becker
>>>>
>>>> On Wed, Oct 8, 2008 at 4:23 PM, Martin Davis
>>>> <[hidden email] <mailto:[hidden email]>> wrote:
>>>>
>>>>     JTS'ers,
>>>>
>>>>     As you may have experienced, buffering in JTS currently has some
>>>>     performance challenges in situations involving large buffer
>>>>     distances.  I'm excited to say that I've implemented some code
>>>>     enhancements which *dramatically* improve buffer performance in
>>>>     these cases (as well as providing an overall improvement).
>>>>
>>>>     I've tested this code as extensively as I can, and am pretty
>>>>     confident that it is robust and accurate.  But it's always good to
>>>>     have other people beat on it as well!
>>>>
>>>>     So, is anyone out there ready, able and willing to test out the
>>>>     new buffering code?  Ideally this would be someone who has a
>>>>     application which uses buffering in a significant way, and which
>>>>     allows determining the performance and correctness characteristics
>>>>     effectively.  I'm looking for feedback to either confirm that this
>>>>     really is an improvement, or some test cases which reveal issues
>>>>     if there are any.
>>>>
>>>>     If you're able to help out, you can either download and build the
>>>>     codebase from CVS, or I've built an alpha release of JTS 1.10
>>>>     which is available here:
>>>>
>>>>     http://tsusiatsoftware.net/jts/files/jts-1.10-alpha.zip
>>>>
>>>>     Thanks - Martin
>>>>
>>>>     --     Martin Davis
>>>>     Senior Technical Architect
>>>>     Refractions Research, Inc.
>>>>     (250) 383-3022
>>>>
>>>>     _______________________________________________
>>>>     jts-devel mailing list
>>>>     [hidden email]
>>>>     <mailto:[hidden email]>
>>>>     http://lists.refractions.net/mailman/listinfo/jts-devel
>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> http://amusingprogrammer.blogspot.com/
>>>> ------------------------------------------------------------------------
>>>>
>>>>
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>>>>  
>>>
>>
>>
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>

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