Nef_3 Package
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Nef polyhedra in 3D. See:

    W. Nef: Beitraege zur Theorie der Polyeder. Publ. Herbert Lang,
    Bern, Switzerland, 1978.

    H. Bieri: Nef Polyhedra: A Brief Introduction. In Computing 
    Suppl. Springer Verlag, Vol. 10, pp. 43--60. 1995.

The implementation represents Nef polyhedra following the Reduced
Wuerzburg Structure as local neighborhood of the minimal elements
in the incidence relation and a global structure, called Selective
Nef Complex (SNC), encoding the incidence relation between the 
local neighborhoods.
   We use an infimaximal box to bound all infinite elements and
obtain thus only vertices as minimal elements in the incidence relation.
The local neighborhood of vertices is represented as sphere maps (SM),
an embedding of 2D Nef polygons on the sphere.
   The global structure links the local Sphere Maps together with 
oriented edges, oriented facets with boundary cycles that consist 
of oriented edge-uses, shells that are edge-use connected facet 
components, and volumes that are bounded by shells. Each element 
is marked whether it belongs to the selected point set or not.


Files concerning the global Selective Nef Complex (SNC):

SNC_items.h             items classes (Vertex, Halfedge, Facet, Volume objects)
SNC_structure.h         the SNC class, global structure, allocation and
                        deallocation of objects, global iteration etc...
SNC_decorator.h         decorator for global SNC structure 
                        (topology exploration)
SNC_iteration.h         iteration macros for project
SNC_io_parser.h         input and output of SNCs
SNC_constructor.h       construction of basic SNCs and global construction
                        algorithm (from SMs to SNCs)  
SNC_point_locator.h     naive point location in SNCs
SNC_visualizor_OGL.h    visualization of SNCs in a OpenGLUT viewer

All files starting SNC_SM are concerned with sphere maps:

SNC_SM_const_decorator.h        exploration of sphere maps
SNC_SM_decorator.h              decoration of sphere maps (mutation)
SNC_SM_checker.h                checking functions
SNC_SM_point_locator.h          point location in sphere maps (naive)
SNC_SM_triangulator.h           triangulation of sphere maps (extern)
SNC_SM_visualizor.h             visualization of sphere maps
SNC_SM_io_parser.h              input and output of sphere maps

SNC_FM_decorator.h              functionality for facet structures

