Formal Notation



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Formal Notation

The simplexes are -dimensional manifolds (subsets) of . A triangle in two-dimensional space is conceptually different from a triangle in three-dimensional space. In order to distinguish these to cases and to unambiguously denote a -dimensional simplex in -dimensional space we write symbolically

has the following basic properties

The simplex is defined by its bounding sub-simplexes.

and, vice versa

Furthermore, we may confine our considerations to

as we have no useful semantics for, e.g., two-dimensional tetrahedrons.

Visualization does of course not work with single simplexes, but with sets of several simplexes which approximate more complex geometrical structures. The visualization operations are always performed on simplex-sets and yield other simplex sets (with different dimensions) as result.

We denote

a set of -simplexes in -dimensional space which can be imagined as a piecewise linear approximation of a general -dimensional manifold (curved objects) in .

The input/output requirements of the operations define their relationships and hence imply the possible combinations of the visualization modules.



Martin Stiftinger
Thu Oct 13 13:51:43 MET 1994