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>Geometrical Object Hierarchy</H1
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>Table of Contents</B
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><DT
><A
HREF="gts-object-class.html"
>Object class</A
> -- parent class for all GTS objects.</DT
><DT
><A
HREF="gts-container-classes.html"
>Container classes</A
> -- </DT
><DT
><A
HREF="gts-containee-classes.html"
>Containee classes</A
> -- </DT
><DT
><A
HREF="gts-points.html"
>Points</A
> -- point object and related functions.</DT
><DT
><A
HREF="gts-vertices.html"
>Vertices</A
> -- vertex object and related functions.</DT
><DT
><A
HREF="gts-segments.html"
>Segments</A
> -- segment object and related functions.</DT
><DT
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HREF="gts-edges.html"
>Edges</A
> -- edge object and related functions.</DT
><DT
><A
HREF="gts-triangles.html"
>Triangles</A
> -- triangle object and related functions.</DT
><DT
><A
HREF="gts-faces.html"
>Faces</A
> -- face object and related functions.</DT
><DT
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>Surfaces</A
> -- surface object and related functions.</DT
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> GTS uses a simple object system implemented in C which allows all
the basic paradigms of object-oriented programming: inheritance of
class members and virtual functions overloading in particular.
</P
><P
> The class hierarchy is implemented via a hierarchy of nested C
structs and type casting. In order to avoid "wild" type casts
between objects belonging to incompatible classes, type casting is
done through macros which check if the conversion is valid. This
type checking is however relatively expensive and can be disabled
on production code by omitting the GTS_CHECK_CASTS define at
compile time.
</P
><P
> The basic geometrical objects of GTS do not have any support for
attributes such as color, texture coordinates, material properties
etc... which may be of interest when using GTS for graphical
applications. This choice was made on purpose in order to keep GTS
as general as possible. Using object inheritance it should however
be easy to extend the base classes to fit your personal needs.
</P
><P
> When destroying geometrical objects you must keep in mind their
geometrical relationships. Destroying a vertex also destroys all
the edges using this particular vertex, destroying an edge
destroys the triangles. Vertices, edges or faces not used by any
segment, triangle or surface respectively are considered to be
"floating" objects. When initially created all vertices, edges or
faces are floating. Destroying a segment, triangle or surface will
cause the destruction of any new floating vertex, edge or face.
</P
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