The Arbitrary Storage Of Lidar Data Can Serve To Obscure The 3d Spatial Information Contained Within The Data. This Presentation Will Compare The Benefits And Deficiencies Of The Octree And The Kd Tree Data Structures Both In Visualization Optimizations And Algorithm Data Access In Open Source Opticks. Discussions Will Include Tradeoffs Between Display Optimizations Including Clipping, Panning And Zooming And Algorithm Data Optimizations Including Nearest Neighbor, 3d Plane Fits, Gradient Mapping, Intensity Mapping, Line-Of-Sight Algorithms, And Autonomous Landing Site Determination.

Increased participation in neogeographical aerial image mapping techniques such as kite, balloon and other unmanned aerial systems has shown the need for open source tools to work with the data. The imagery acquisition field techniques introduce remote sensing to a host of new users that are able to interact with data in ways previously made impossible by cost, education, and ease of acquisition of imagery. Mapmill.org and Cartagen Knitter are presented as crowdsourcing tools for sorting through raw flight data and rectifying the imagery. Participation in the sorting is easier than image rectification, thus separation of the tools.

Mapmill.org works towards sorting and organizing raw flight data in a simple web application. Imagery is interactively displayable in different fields and users sort through raw data by assigning values to separate images that are accumulated.

Cartagen.org Knitter works to rectify aerial imagery by warping the data dynamically in overlay with base orthoimagery data in a web application. The resultant map is viewable at Cartagen.org and GIS exportable. These tools work together towards participatory mapping at the community level.

Node.js is a library built on Google's V8 javascript engine, which does non-blocking evented I/O via the libeio library. V8 is incredibly fast, (much faster than ruby/python) and can be used to create web-applications that can handle thousands of concurrent connections and real-time data. This tutorial will go through the process of creating an asynchronous and realtime geospatial web-app using the Node.js javascript server and bindings for the geo-stack. At the end of this tutorial we will have built a web application that can handle multiple client connections and a RESTful API to push data to a persistant storage such as PostGIS, Spatialite or MongoDB. The web application will allow multiple clients to be notified of updates posted in real-time using the API we built. The real-time communication be achieved using the HTML5 WebSocket client and server API written in Javascript. The workshop is aimed at people who wish to learn more about real-time, non-blocking geospatial web services and applications. We will also provide some insight into possible hosting of such web applications.