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1. #GPSMAPEDIT CONDENSING NODES IN POLYLINES FREE AND OPEN#
2. #GPSMAPEDIT CONDENSING NODES IN POLYLINES CODE WILL CREATE#

Multiple topologies can now be cut against each other, yielding complex analysis results from a simple selection process. Links, polygons and nodes, can be added to a topology, as easily as drawing a polyline. Map Plus enhances the topology functions of AutoCAD MAP.

Get the geographic data on streets from OpenStreetMap. That would put the stories on a user’s mental map of the streets they walk every day and allow them to see their own neighborhood and city in a new way (indeed, the first thing almost any SF resident seems to do with the finished product is zoom to their own street and start working their way outwards).I had a general vision for the project in my head, and I knew the basic recipe would look like this: But I felt that connecting it to the geography of the streets was the key. Then, click the draw arrow.The 'Add Nodes' function in MapCAD tools can be used to achieve this by following the steps below: After loading MapCAD via the Tools menu, select the polyline object of interestA question worth asking before starting a project like this: why put it on a map? After all, if someone wants to learn the histories, there are plenty of existing books and websites for that. It is most important to make sure the polyline button is active. Just move the control lines until you get the curve that you want.

Gpsmapedit Condensing Nodes In Polylines Free And Open

Any list of nodes can be drawn as a jagged line from node to node, which can represent something like a street if the last point is the same as the first, you’ve got the boundary of a closed shape, which can represent something like a building or a park.The actual XML looks something like this:With a little bit of parsing to link up the tags with the latitude and longitude of the corresponding tags, you can get something like this, a nice JavaScript-friendly array of lat/lng points (a polyline):,]I took all this data, filtered it by county (San Francisco is a consolidated city-county), and dumped it into three database tables: a table of ways with all of their extra properties (we’ll need some of those later), a table of nodes, and a table of way-node relationships. A way is an ordered list of nodes, and OpenStreetMap uses it to define pretty much any geographic feature. This cut down the uncompressed file size from 370 GB to a much more manageable 46 MB.OpenStreetMap data is XML, and largely consists of nodes (latitude/longitude points) and ways. I gave up on that and switched to the BBBike OpenStreetMap extractor, which lets you draw a rectangle on the map and get an OSM extract for that area only (it’s one of many helpful extract tools). The data is user-contributed, so the coverage isn’t perfect, but it’s getting better every day, and it’s especially thorough in a sizeable city full of cartography nerds like San Francisco.I started out trying to wrangle the OpenStreetMap planet file, all 27 compressed GB of it, but it gave me a lot of headaches (at one point, I left it to decompress on an Amazon EC2 micro instance, and it was still decompressing three days later). Use Leaflet to combine them into a lush, clickable full-screen map.Seems simple enough, right? What followed was a textbook case in the unavoidable messiness of real-world data and how the smallest design detail can make the biggest difference.OpenStreetMap is a fantastic resource, a free and open set of natural and human geographic data for the entire world.

I knew I wanted a tile-based slippy map, and rather than dive into TileMill and drive myself crazy nitpicking the aesthetics (plenty of time for that later), I decided to take advantage of Stamen Design’s beautiful Toner Lite map tiles. To a human being, this is a Safeway parking lot, but it’s also officially a street named Reservoir Street:After lots of data cleaning, I eventually ended up with a pretty accurate set of 2,169 named roadways and the coordinates required to draw them. There are some naming inconsistencies:OSM also reflects the natural complexities of real-world roads. Once I increased that, I was back in business.OpenStreetMap is pretty great, but every dataset has its quirks.

Gpsmapedit Condensing Nodes In Polylines Code Will Create

I knew I’d have to do something about this, but I wasn’t sure what yet. They make terrible targets for clicking and hovering. Streets are really skinny. This code will create a basic tile map, restrict the view to San Francisco, and add each street to the map with a basic hover and click event.//Initialize the map with a starting view and a generous maximum boundaryMaxBounds: ,].fitBounds(,]) L.tileLayer(') //Update the infobox with the street infoHoly polyline explosion, Batman! Fooling around with this basic prototype clued me in to two things I needed to start thinking about:

When you zoom, the relative size of the streets changes the lines become way too thin or way too fat and stop matching the outlines on the underyling tiles. For a map with hundreds or thousands of overlapping lines, it’s a disaster. For a basic map with a few shapes on it, it might be OK if this stays constant as you zoom in and out. I could make my JavaScript less bad and improve this a bit, but probably not by the order of magnitude that was clearly required.Another specific issue that came up was polyline thickness (or weight) which is defined in pixels. It broke Firefox, and forget about IE or mobile browsers.

You have lots of streets with utterly self-explanatory names (e.g. Some street names have backstories that are available but pretty banal. I also found myself grappling with two tough questions throughout the process:Diving into the histories forced me to start considering what was actually worth putting on a map like this (are you sensing a “lack of forethought” theme here?). I learned a ton about not just local San Francisco history, but California and US history too. It was a giant scavenger hunt, trying to find information on not only who a street was named after, but why.Compiling the actual histories and condensing them into something readable was extremely time-consuming, but it was also a lot of fun.

Vista Verde Court).Was there any point in putting these on the map? Keeping the performance concerns and general risk of clutter in mind, I decided I wasn’t going to include these or other ahistorical categories.