A place in history: a guide to using GIS in historical research

CHAPTER 6: VISUALISATION FROM GIS

6.7 Moving and interactive imagery

Animation is an area that has much to offer historians. Traditional paper-based cartography is poor at presenting change over time, while animations clearly have the potential to do so. If one aim of GIS is to be able to explore and present data with the maximum amount of both spatial and temporal detail possible, then this may seem like an ideal way of approaching the subject. There are a large number of modern file formats that allow the researcher to create animations, from animated GIFs where a number of GIF images are stitched together sequentially, through to more complex video formats such as AVI and MPEG. While the technical issues associated with producing animations are well developed, the cartographic issues are still in their infancy. As a result, researchers working in this field need to be careful to remember that the aim of producing animations is the same as with any other type of mapping: to produce a clear and understandable abstraction of the data and the patterns held within them. It is easy to become seduced by fancy graphics that convey little of real value, and the cartography of animation is, as yet, poorly understood.

Moving imagery can be used to do more than simply present time series. It can also be used to change view points or even to fly-through virtual landscapes. A good example of this is provided by Harris (2000). He is researching an ancient burial mound and sacred space in Moundsville, West Virginia, and wanted to re-create the landscape that would have existed around the mound. By combining historical and archaeological evidence on the ancient landscape with modern data on relief he is able to create a digital terrain model of the landscape. This is draped with a representation of the possible land cover of the time. The user is then able to zoom in and out of the landscape and fly-through it to view it from any angle or perspective that they are interested in. As with animations, this is an interesting research area but efforts must be put into conveying information to the user and not simply producing fancy graphics with gimmicky file formats.

There has been increasing interest over time in mapping on the Internet. Maps and images such as those produced by Ray are indeed available over the web (Ray 2001). While the web is a good medium for raster images and a variety of animation and multimedia formats, as yet putting vector graphics on the web is still fraught with problems, despite vendor claims to the contrary. This is partly a problem of reliability and partly a problem of performance. Java offers one way of putting vector images onto the web (see Southall et al. 2001), however, these require low-level programming skills. Once it is technically easier to put vector graphics on the web there will still be many cartographic issues to resolve.