State of the JTS Topology Suite - A Conversation with Martin Davis

August 24, 2011

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Amber Weber (AW): What made you decide to get into the geospatial field?

Martin Davis (MD):
I have a degree in math which developed my interest in mathematically oriented algorithms, which geospatial has a lot of. Also, I used to draw a lot as a kid. I like visual things so the connection with mapping is pretty strong. I actually took a course in university on computational geometry which is the theoretical basis for geospatial. I found it quite interesting so I thought I would check out this thing called GIS, which at the time (in the early ‘90s) was not nearly as prevalent as it is now. It was a little more obscure.

AW: So you didn’t go to university with the plan of getting into the geospatial world?

No, I took computer science. I got a job for the Ministry of Forests in the mid ‘90s and I ended up working in a section in the IT group that was specializing in advanced spatial applications, and that’s when I really got the bug.

AW: And now you’ve been at it for what, 15 years?

Yes, over 15 years now.

AW: So in those fifteen years what would be some of the highlights?

Definitely developing the JTS Topology Suite, which is the topic of the talk that I am giving at the FOSS4G conference. The JTS project has been running for 10 years now and is used all over the world. It’s really been interesting to work on and has spawned a lot of ... imitators shall we say, so that has been very satisfying. I also did a project called the JUMP Unified Mapping Platform, which is an open source project that has taken on a life of its own. That was really fun to work on because it was a graphical user interface platform, so very visually oriented.

Another interesting project was the Corporate Watershed Base for the Ministry of Agriculture and Lands. The project involved building a stream network and a terrain model for the entire province of British Columbia in order to compute watersheds for all the streams in BC. That was quite a challenge, but it worked out really well and produced a very useful dataset.

AW: Let’s focus on the JTS Topology Suite presentation at the FOSS4G conference in Denver. How did that come about? Did you apply?

Yes, I applied to do a presentation at FOSS4G. They have a community voting process to decide which presentations are picked.

AW: Why FOSS4G? Why did you choose that conference?

A couple reasons: It’s a great conference; everybody in the open source geospatial world will be there. This is THE big conference for open source geospatial and JTS is an open source geospatial library so it’s the perfect venue for it. Also, I know a lot of the people who are going to be at the conference and I’ve been to a couple before, including the one in Victoria in 2007 and it’s always a really educational experience.

AW: You presented at the 2007 conference too, right?

Yes, I gave two presentations, one on JTS and one on JUMP.

AW: And is your presentation this year going to be different than those two?

It’s a follow-up to what I did in 2007; basically it’s updating people on the state of JTS. The presentation in 2007 was on JTS as it existed then and there’s been a lot more enhancements so I’ll be talking about those. And I’ll be talking about some of the future directions.

AW: What part of the conference are you most excited about?

Meeting my peers in the geospatial world. There’s going to be lots of great talks there and that’s exciting too. But the main thing is getting face time with other “movers and shakers” in the open source geospatial world.

AW: I hear you may have been nominated for an award! Is this true?

Possibly! Some colleagues in the JTS community said they were going to nominate me for the award. I don’t think the nominations are public so I’ll just have to wait and see!
The award is the Sol Katz award that the OSGeo organization gives out every year to honor someone who’s made a significant contribution to open source geospatial technology.

AW: Best of Luck!

MD: Thanks.

AW: Is the presentation going to be podcast?

That’s a good question … the slides will be available for sure. I think sometimes the presentations are filmed too.

AW: Can you go into more detail on what JTS is? Is there a summary you can give?

It’s a library of basic routines for dealing with the kinds of geometry that are commonly used in GIS systems. For example, computing the area of a polygon or the length of a line, or the result of intersecting two lines or polygons together. Every GIS system needs this functionality.

AW: What was your inspiration for developing JTS?
I can’t take credit for that actually! It was a client in the BC government, Dr. Mark Sondheim. He had the idea and he arranged funding for the initial development of it.

AW: And you got to take it and run with it?

Yes, lucky me!

AW: And here you are now. Is it profitable?

No, it’s not at all profitable.

AW: Labor of love then?

Yes, pretty much. I’ve had a few small support contracts over the years, from various interested parties.

AW: But you get the rock star esteem!

Haha, yes... the limos and the girls and all that.

AW: You’ll have a star out on the sidewalk soon.

Yes, the Geospatial Walk of Fame


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