Thursday, 30 April 2009

Having the Map - Base Mapping in Geotime

Finally I managed to get some kind of data from ArcMap linked into GeoTime as a base map. The projection that works is only WGS84, but most of the data we have her obviously is in British National Grid. So some transformation is required. This very often results in some funny shapes and suddenly you go, wow, I haven’t seen greater London as this kind of squashed tomato shape yet. Another problem is to get the transformed files to match up, and so on. It is confusing.
But her we are at least the Greater London area is there and the river Thames.

Image by UrbanTick for UrbanDiary - Location points with river Thames (far left), inner and outer London (centre), London regions (right)

And then even the buildings appear, imported from the Virtual London Model, developed here at CASA. They are slightly out of place but there they are.

Image by UrbanTick for UrbanDiary - zoom Kings Cross with location spots

Next step will be to ad some detailed information to the GeoTime data. At the moment it only represents track point location data. But with the series of interviews that are underway at the moment some more detailed data about the participants activities are available and GeoTime could be quite helpful in relating these different types of information.

Image by UrbanTick for UrbanDiary - lines of activity, zoom Kings Cross (left), Kentish Town East (right)

These Images are screen shots taken from GeoTime with the software’s internal screen grabber. The top view was used to get the displayed GP data to mach properly with the imported base map. For visualization purposes this was seen to be the easiest way o understand what was going on. By switching into 3d view things get complicated and it is difficult to make sense from the combination of data that moves up and down in time and a base layer with a static map. Specially when zooming in to see details. The feature to replay the data can be helpful in this situation though. The map then acts as the division between past and future, basically the present. A location dot is used to mark this position.

Image by UrbanTick for UrbanDiary - 3d view in GeoTime


An update on this mapping topic.

The issues where something I talked about with Curtis from GeoTime. He suggested that a very quick fix is a available through the recourses in ESRI ArchGIS. They actually offer a number of base map under file, free recourses in 9.3 the world street network works quite good for the London location. And after I found the slider to adjust the map transparency I was quite happy with the result.

Image by UrbanTick for UrbanDiary - central London view with ESRI recourse base layer imported from ArcGIS

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