mirror of https://github.com/CGAL/cgal
71 lines
2.4 KiB
TeX
71 lines
2.4 KiB
TeX
% +------------------------------------------------------------------------+
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% | Reference manual page: area_2.tex
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% +------------------------------------------------------------------------+
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% | 21.06.2001 Author
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% | Package: Polygon
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% |
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\RCSdef{\RCSareaRev}{$Revision$}
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\RCSdefDate{\RCSareaDate}{$Date$}
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% |
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%%RefPage: end of header, begin of main body
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% +------------------------------------------------------------------------+
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\begin{ccRefFunction}{area_2} %% add template arg's if necessary
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%% \ccHtmlCrossLink{} %% add further rules for cross referencing links
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%% \ccHtmlIndexC[function]{} %% add further index entries
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\ccDefinition
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The function \ccRefName\ computes the signed area of a polygon.
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\ccInclude{CGAL/Polygon_2_algorithms.h}
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\ccGlobalFunction{
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template <class ForwardIterator, class Traits>
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void
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area_2( ForwardIterator first, ForwardIterator last,
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typename Traits::FT &result,
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const Traits& traits);}
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{
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Computes the signed area of the polygon defined by the range of points
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\ccc{first} \ldots\ \ccc{last}. The area is returned in the parameter
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\ccc{result}. The sign is positive for counterclockwise polygons, negative for
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clockwise polygons. If the polygon is not simple, the area is not well defined.
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The functionality is also available by the \ccc{polygon_area_2} function, which
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returns the area instead of taking it as a parameter.
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}
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\ccHeading{Requirements}
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\ccIndexSubitem[C]{bottom_vertex_2}{requirements}
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\begin{enumerate}
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\item \ccc{Traits} is a model of the concept
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PolygonTraits\_2\ccIndexMainItem[c]{PolygonTraits_2}.
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Only the following members of this traits class are used:
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\begin{itemize}
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\item \ccc{Compute_area_2} : Computes the signed area of the
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oriented triangle defined by 3 \ccc{Point_2} passed as arguments.
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\item \ccc{FT}
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\item \ccc{compute_area_2_object}
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\end{itemize}
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\item \ccc{ForwardIterator::value_type} should be \ccc{Traits::Point_2},
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\end{enumerate}
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\ccSeeAlso
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\ccRefIdfierPage{CGAL::polygon_area_2} \\
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\ccRefIdfierPage{PolygonTraits_2} \\
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\ccRefIdfierPage{CGAL::orientation_2} \\
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\ccRefIdfierPage{CGAL::Polygon_2<PolygonTraits_2, Container>} \\
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%% \ccIncludeExampleCode{examples/Polygon/area_2_prog.C}
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\end{ccRefFunction}
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% +------------------------------------------------------------------------+
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%%RefPage: end of main body, begin of footer
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% EOF
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% +------------------------------------------------------------------------+
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