1 \section{\Index{Hollowing out
} a solid's faces
}
3 We call
\textit{hollowing by the ratio $k$
} an operation, which for a given
4 face with the center $G$, executes a dilation on that face with the ratio
5 $k$, then divides the original face with using this new face.
7 For example, a cube with a hollow of its top face with a ratio of $
0.8$:
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22 The option
\Lkeyword{affinage
} allows us to hollow a solid's faces either globally or
23 individually. This option uses the key
\Lkeyword{affinagecoeff
}
24 (value $
0.8$ by default) which indicates the ratio $k$ used for the
28 \item \texttt{\Lkeyword{affinage
}=
\Lkeyval{all
}} hollows all the faces;
29 \item \texttt{\Lkeyword{affinage
}=
0 1 2 3} hollows the faces
0,
1,
2 and
3;
32 When a face is hollowed out, the default behaviour suppresses the resulting central
33 face. However, the option
\Lkeyword{affinagerm
} allows us to conserve that central face.
35 When we conserve the centre face, it is---by default---drawn with the same colour
36 as the original. The option
\Lkeyword{fcolor
} permits to specify another colour.
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