Database Reference
In-Depth Information
FIGURE 3.7
Portobello: more detail information from the gazetteer for Scotland.
3.4.3 t
Terrain
m
odels
and
t
hree
d
imensions
Terrain models are used to represent the height of a landscape, typically the height of
the land's surface with buildings and vegetation removed. Such models are useful for
analysis, such as flood modeling. More recently, there has been a general interest in
producing three-dimensional (3D) models with buildings represented in 3D to vary-
ing degrees of precision. These models have many potential uses but are so expen-
sive to produce that, at least at the time of this writing, economically viable uses are
few and far between. At present, where such models exist, they are mostly to show
how new developments might fit into an existing landscape or are demonstrations of
the art of the possible and to aid the planning of security at large public events.
3.4.4 d
iGital
F
eature
m
odels
A digital feature model is a representation of the geography of an area, specifically
discrete landscape features and their relationships to each other, typically con-
structed using vector and network data. The data is stored in a database, allowing
sophisticated analysis to be performed on the features. Such models therefore go
beyond cartographic visualization of maps and are also more than gazetteer indexes.
Feature models enable a vast range of possible uses for GI, including environmen-
tal analysis, routing, health analysis, insurance risk calculations, placement of retail
