Main Page

The site is a Wiki; you are invited join and add pages or edit them.

A shortcut to ssh into mercury

Geospatial technology

Some current projects, mostly for City of Corvallis

ArcGIS
MapServer
Corvallis Mapserver project logbook
ArcIMS + ColdFusion + MapOptix
ArcPad including notes on PDAs

Here is the ArcXML Programmer's Reference Guide. To tweak ArcIMS servers and viewers you really need to know ArcXML. It's used for ArcPad configuration too.

Here are a few notes left over from a paper I wrote on Archaeology for a GIS class.

the GoogleEarth section

I looked at it and yawned, I must be jaded. So many people have told me it's the neatest thing since sliced bread so I must have missed something. Maybe it was the 300 hours I have already spent working with ESRI 3D Analyst; been there done that.

Okay, so it was the only session at NWGIS that was packed. Okay, so I will look at it again. The presenter there from Pierce County has managed to have fun with it so maybe I can too.

To me what's cool about it is that it streams both the DEM and raster photo data from a server so that everything appears seamless; I don't have to locate and download the layers and then load them into my own ArcScene project. I wish that Hawaii would break down and have some high res photos done. I am getting tired of these LandSat images.

What the Pierce county guy did was overlay his own data on the GoogleEarth maps. He did that by writing his own KML files. GoogleEarth used to be Keyhole so the language it's based on is called KML which is (what else) an XML variant.

KML documentation

What can I do with it

I can add a raster layer to the map using GroundOverlay. The raster is referenced with an href tag; it can be anywhere (URI) or it can be a file on the local network.

I can add PlaceMarks to the map.

I can draw points, lines, and polygons onto the map.

I can put a text overlay layer onto the map

I am thinking that I should be able to insert the locations of all the CDS Wireless GPS receivers onto a GoogleEarth map...

Links to other Google Earth places

Global Connection is a project to tie National Geographic data to GoogleEarth.

Some issues to think about

What are people doing for revision control with spatial data? I know ArcSDE has some form of versioning but have not had time to read up on it yet. ArcSDE costs money, uses expensive RDBMS as a backend, and I don't have access to a copy right now so I am not motivated.

Seems like a vector-based revision control system would not be impossibly difficult to implement. You could keep it in a spatial database and query on changes. "Show me all changes to the parcel database in the last 6 months". Rasters don't really get editted in GIS systems; either you have a new ortho photo or you don't, so storing the entire copy of each raster is not so bad. A query is "Show me the photo for this area for 1996", not "show me what changed between these two photos".

I talked with Toshimi Minoura yesterday and he said that there is a school in Germany that has been working on this problem (esp as it relates to editing and updating databases) for many years.

How can we best apply Flash to online cartography? The apps I have looked at so far use it for the user interface. It's regarded by some as an improvement over Javascript because the two predominant browsers have independently developed versions of Javascript that work differently, whereas Flash plugin comes from one company so it's more consistent across browsers and platforms.

We could also use it directly in the maps. For mapserver, see Flash support in Mapserver

Server side vs client side user interfaces for web mapping It's not really a matter of 'versus' rather than 'where do we draw the line?' Some things HAVE to be on the client. Others can be implemented in either place.

For significant work such as editting and updating we still need a desktop app. Web mapping should be used more for display and simple analysis, with a desktop app communicating with central data stores as the model for editting and advanced spatial analysis.

Fuzzy thoughts -or- Who gets to decide where the shoreline is, and why isn't it fuzzy?

For georeferencing historical maps, can we use a fuzzy confidence overlay to indicate what areas of the map look good spatially and what ones don't?

Fuzzy GIS articles

GIS-based fuzzy c-Means clustering analysis of urban public transit network service: The Nanjing City case study

Integrating exploration dataset in GIS using fuzzy inference modeling

Stuff to look at in more depth

Refractions developed PostGIS
Manifold GIS software
Remote sensing
GRASS Open source GIS software
Elkhorn Slough Wireless Project Spring 2003 CSU Monterey Bay project
Clipping orthophotos Process used in CDS Wireless project

Cartography

To learn more than you could want to know about color and shading on maps, visit these sites.

http://www.reliefshading.com/ has articles by Bill Patterson of the National Park Service on producing 2d and 3D maps using natural colors.

http://shadedrelief.com/ has lots of information on shading techniques and very interesting articles about cartographers.

Geobuzzword Compliance section

ACSM ASPRS: American Society for Photogrammetry and Remote Sensing
AGU: American Geophysical Union
SAF Hydrophiles Oceanography Geology Hydrology Forestry Biometrics
SCGIS Society for Conservation GIS
SAS

Electronics

File:Bfd background.gif Yellowstone Weatherstation

WiFi -- WRT54GS project

GIS/GPS links

Contacts

Data sources not for the whole world, just the parts of it that interest me.

The GIS/GPS tools page has information on obtaining and using GIS and GPS tools.

The Community Portal has more links to other places.

The NGA Map Rescue program

Web stuff

Beginner's guide for Drupal I quit working on this when I quit using Drupal.

Some images

Airport area maps done for Paul