1 research outputs found
Spatial models in computer-based information systems
From a series of initial studies in the area of computer cartography
a dual data structure was evolved based on matrix representation of
graphs and the use of boolean expressions. This data structure was used
principally to represent zones in space though, by using boundaries of
zones, it was possible to create line networks.
The original idea was to use the boolean expressions as an input language
for creating volume and area descriptions and to use the graph matrices
for internal manipulation and creating graphic output. However, a way
was found to interpret the boolean expression directly into the form of
graphic output suitable for the raster scan displays given by television
monitors.
The software implementation of this process was very slow but, with the
current developments in integrated circuitry, it suggested a way of
creating a new form of parallel display processor. This possibility was
investigated initially as a general processor to carry out several related
spatial operations and then, finally, merely to create displays.
The applications depend on (t) the general nature of the data structure
used and the possible graphic languages it makes possible and (2) the
real time manipulation of displays. In the case of three-dimensional
scenes, this includes an automatic hidden line and hidden area removal
capability.
The particular applications which have been considered include the fast
access and display of maps and technical drawings from planning, archi¬
tectural and engineering data bases; the real time generation of displays
for training simulation; the preparation of animated films for teaching
and entertainment; the control of numerically-controlled machine tools;
and solving the placement problem in computer-aided design work and
overlap problems in type setting and map annotation