| B. Jenny, BENDING TYPE TO REPRESENT THE THIRD DIMENSION OF TERRAIN ON MAPS |
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Geographia Technica, Special Issue, 2010, pp. 65 - 67 BENDING TYPE TO REPRESENT THE THIRD DIMENSION OF TERRAIN ON MAPSBernhard JENNYABSTRACT: Many 3D maps show type with considerable distortion, resulting from draping 2D maps
directly onto digital elevation models. Distortion is caused by perspective foreshortening
and by the irregular shape of the terrain surface. Characters are compressed, expanded,
skewed, occluded and misaligned, producing distorted text labels that are difficult or even
impossible to read.
However, deformed type can also function as a visual clue indicating the shape of the
terrain. When rendered in a perspective view, draped text labels traverse hills and valleys
along curved lines. The curviness of these lines reflect the shape of the terrain. This paper
draws inspiration from this observation encountered on 3D maps, and replicates this effect
for standard 2D orthogonal maps. Type deformed in this way not only provides textual
information, but also suggests the third dimension of the terrain.
A method is presented that bends text along a curved line following the terrain. The line is
extracted from a digital elevation model. The amount and direction of bending can be
controlled by a user-definable parameter. The more the label is bent, the closer it follows
the undulations of the terrain and better portrays the shape of the terrain, but the more
difficult it is to read. |
