GIS Import Utility

After many episodes over the years of manually cropping GIS layers in ArcMap, extruding buildings and offsetting terrain with a Sketchup plug-in, and then manually draping edges onto the terrain to cut out streets... I decided to put some Grasshopper and Visual Basic to good use. Introducing GIS import...

Unlike some of the more advanced methods of reading shape files directly into Grasshopper, I've opted for a simple system of text stream parsing, which requires a few utilities are run on a shape file prior to using this GIS import utility, but this only needs to happen once per GIS set. Once the shape files have been processed (the polyline vertices and attribute tables are converted to simple .csv files), a user need only enter the parcel number and offsets in each direction and the site is created. Per site model, I would calculate the time savings at 2-3 hours. The process takes approx. 5-10 min. depending on the size of the site and amount of detail, but this runs in the background, so Rhino\Grasshopper isn't locked up during the process.

This is just one component in a series of urban design/planning tools that are being developed. As the tools progress, I'll send out updates.

Replies to This Discussion

Permalink Reply by Mostapha Sadeghipour Roudsari on August 23, 2012 at 1:03pm

This is awesome!

Permalink Reply by Rémy Maurcot on September 11, 2012 at 4:57am

Hi Nathan,

Verry good job. What are the features that you developed in VS and in the grasshopper?

Permalink Reply by Nathan Lowe on September 13, 2012 at 12:50pm

Thanks!

VS parses the csv file (which has been generated from the shape file) and crops the objects based on the 2D extents chosen in the menu and then outputs a new abbreviated csv file... then GH reads those abbreviated text files and converts to geometry (vertex lists into polylines and so on). Terrain is generated from the contours (which are moved to elevations specified in the csv files) and buildings are extruded in much the same manner. I owe much of the terrain building definition to other posts on the discussion board (search "terrain" or "TIN" I think that should get you to the right place) Street edges and parcel outlines are then draped onto the terrain and the srf split function is used to separate streets from parcels, etc.

Permalink Reply by Adam Laskowitz on September 13, 2012 at 12:37pm

Where can we download this?

Permalink Reply by Nathan Lowe on September 13, 2012 at 12:54pm

I'm going to be finishing this up next week and should be able to share it then, unless of course, the higher ups object. But either way I will post an update and let you know.

I was trying to find a way around using ESRI software to get the initial csv files from shape files. I initially used GrassGIS, but then realized a handful or more people who had written simple shape file to ascii (csv) converters. The utility that I run to convert the csv files to be read by GH includes using one of these converters. Find at http://arcscripts.esri.com/details.asp?dbid=12689

Permalink Reply by Nathan Lowe on October 8, 2012 at 3:40pm

Okay, so I've updated the interface and will post separately under the new name of the project: Meerkat.

Permalink Reply by Toussaint Jimenez Rojas on November 17, 2012 at 3:28pm