Category Archives: OSGeo

The SurveyOS Project’s SlitherGrid Toolkit

On January 19th, 2013 the California Chapter of the OSGeo is holding a hack-a-thon. I hope the geogeeks present will be interested in hacking on a new toolkit from the SurveyOS Project called SlitherGrid. Here is a description of the toolkit:

SlitherGrid is an open source toolkit for geospatial raster data processing written in the Python Programming Language. Its focus is on non-traditional raster data (LIDAR, elevation rasters, and other “non-optical” raster datasets). The toolkit is currently in a conceptual stage, although there is preliminary source code available on the SurveyOS Project SVN code repository.

Design Goals

The immediate design goals of the SlitherGrid Toolkit are:

  • Pure Python implementation with no dependencies on C programming language libraries.
  •  Ease of use.
  • Support for basic raster processing operations on 2D raster data grids.
  • Support for basic GIS and land surveying data formats.
  •  Pluggable software architecture that supports easy customization. This includes (1) the addition of support for additional raster and vector data formats, and (2) the addition of additional raster processing algorithms and tools.
  •  Built-in geospatial functionality. (The grids aren’t just simple arrays of numeric values. They support geospatial opertaions.)

The long term design goals of Slither Grid Toolkit are:

  • Support for multi-threading.
  • Support for 3D raster data grids.

Conceptual Toolkit Architecture Summary

The conceptual code of the toolkit is currently organized into four (4) Python modules. contains all of the classes for simple 2D raster data grids. (These are called “SlitherGrids”). contains utility geometry classes used to represent coordinates, angles, and simple vector geometry. contains classes that support basic file input/output, allowing the user to create 2D grids from common raster data formats. contains classes that can take a 2D raster grid and paint, or render it, to common image file formats for visualization.

The Sunburned Surveyor

Update on OSGeo Journal Volume 11

My work on OSGeo Journal Volume 11 continued today. I updated the California Chapter Annual Report Item to include new member activities from chapter members. I also completed the preliminary PDF versions of the Francophone Chapter and PDX Chapter Annual Report Items. Tomorrow I will work on the last chapter report that was submitted, for the one for the Korean Chapter.

I’m only waiting on one other Annual Report Item, from the Deegree Project.

My next step is to work on HTML versions of the report items so we can get this issue of the OSGeo Journal on the web as well as in PDF. I might also find time to convert the HTML files to EPUB.

The Sunburned Surveyor

Work on the OSGeo Journal Volume 9: 2011 Annual Report

I started work in earnest today on the OSGeo Journal Volume 11. This volume is the Annual Report for 2011. I realize I’m almost 7 months behind, but I hope to have next year’s annual report out by the end of March 2012.

Today I finished the preliminary PDF versions of the California Chapter Annual Report Item and the GRASS Software Project Annual Report Item. I’ll be working on the Korean Chapter, Francophone Chapter, and PDX Chapter annual report items next.

It sounds like we may get a topical article contributed this year. The article will be related to the Geopython Projects.

I’ll also be contributing three or four topical articles to this volume. The first will be an article on sharing GIS data models. It will discuss some of the work I’ve been doing to create a standard GIS model for Sanitary Sewer Networks as part of the CCVGPG Utility Working Group.

I’ll post more about this article and the other topical articles I’m contributing to Volume 11 later.

The Sunburned Surveyor