Visualisation

What is Visualisation?

Generally, scientific visualisation can be seen as a computer-assisted method, which can transform data and results of analyses into visual modes that could otherwise not be seen for instance due to their abstract nature. Thus, visualisation allows us to work very quickly and in an interactive way, with images and their underlying related data.

Visualisation and Cartography

In the context of cartography, concepts of modern scientific visualisation are only starting to be applied and even defined. 3D-visualisation with its continuous x, y and z data, however represents an indisputable advantage for cartography: It reports a three or multi-dimensional reality, while the traditional paper map or screen is limited to "2D or pseudo 3D".
But the complexity of such a multi-dimensional image implies that its application is reserved to a well-prepared public: however attractive the image can appear, its reading can be challenging.
On the other hand, the image and its elements should be designed in a user-friendly way in order to allow an easy and clear interpretation.

Examples of Visualisation of Spatial Data

The diploma thesis of M. Dobler at the Institute of Cartography ETH contains good examples of cartographic data visualisation. They have been realized using the software World Construction Set 4 and shows 3D-visualisations of the Mount Hood area in Oregon/USA.

Find a few visualisations, examples below. For more information click here (external link).

Perspective View 1

A perspective view of Laurance Lake and Mount Hood: Vector data of areas and line elements textured with effects: Trees, water, grass, snow.

Laurance Lake and Mount Hood perspective view

Raw Data used:

USGS 7.5-minute DEMs, 1:24000, Digital Elevation Model, 10-Meter Resolution
USGS 7.5-minute DRGs, 1:24000, Digital Raster Graphics, 4000x6000 Pixels, rgb Colors, 72 dpi
USGS 7.5-minute DOQs, 1:24000, Digital Orthophoto Quads, 1250x1800 pixels, black & white, 72dpi
Oregon Geospatial Data, 1:250000, Forest Lands, Derived from GAP Vegetation

More information about the data used, can be found at USGS Geographic Data Download (external link).

Perspective View 2

A perspective view of Old Maid Flat and Lost Creek: Digital Elevation Model, overlayed with a raster file of the annual precipitation combined with a topographic map.

Old Maid Flat and Lost Creek perspective view

Raw Data used:

USGS 7.5-minute DEMs, 1:24000, Digital Elevation Model, 10-Meter Resolution
USGS 7.5-minute DRGs, 1:24000, Digital Raster Graphics, 4000x6000 pixels, rgb Colors, 72 dpi
Oregon Geospatial Data, 1:500000, Precipitation from USGS

Information about the Oregon Geospatial Data can be found at Oregon Geospatial Database (external link).

Panorama Visualisation

A panorama visualisation from Elk Mountain: Digital Elevation Model overlayed with a combination of the orthophoto and the topographic map. The panorama is made up of 16 images in steps of 22.5 degrees. It was created using "World Construction Set", stitched together with the software "VR Worx" and finally saved as a Quicktime movie. Click on the following picture and move the mouse into the direction you want.

Quicktime 3D visualisation

Raw Data used:

USGS 7.5-minute DEMs, 1:24000, Digital Elevation Model, 10-Meter Resolution
USGS 7.5-minute DRGs, 1:24000, Digital Raster Graphics, 4000x6000 Pixels, rgb Colors, 72 dpi
USGS 7.5-minute DOQs, 1:24000, Digital Orthophoto Quads, 1250x1800 pixels, black & white, 72 dpi

This last example shows a screenshot of a 2D visualisation of statistical data from the Atlas of Switzerland interactive (external link). The software allows interactive queries to be made within the map image.

2D visualisation, Atlas of Switzerland 1 (Bundesamt für Landestopografie swisstopo (eds.) 2000)

Raw Data used:

Digital Terrain Model of Switzerland DTM25
Vector 25, vector 50 (digital landscape models derived from National map)
Geostat: Spatial geographic- / statistical database
Digital general maps of Switzerland