mirror of https://github.com/CGAL/cgal
151 lines
3.9 KiB
TeX
151 lines
3.9 KiB
TeX
|
|
All classes in the \cgal\ kernel provide input and output operators for
|
|
IO streams. The basic task of such an operator is to produce a
|
|
representation of an object that can be written as a sequence of
|
|
characters on devices as a console, a file, or a pipe. In \cgal\
|
|
we distinguish between a raw ascii, a raw binary and a
|
|
pretty printing format.
|
|
|
|
\ccEnum{enum Mode {ASCII = 0, BINARY, PRETTY};}{}
|
|
|
|
|
|
In \ccc{ASCII} mode, objects are written as
|
|
a set of numbers, e.g.\ the coordinates of a point or
|
|
the coefficients of a line, in a machine independent format.
|
|
In \ccc{BINARY} mode,
|
|
data are written in a binary format, e.g.\ a double is represented
|
|
as a sequence of four byte. The format depends on the machine.
|
|
The mode \ccc{PRETTY}
|
|
serves mainly for debugging as the type of the geometric
|
|
object is written, as well as the data defining the object. For example
|
|
for a point at the origin with Cartesian double coordinates, the output
|
|
would be \ccc{PointC2(0.0, 0.0)}. At the moment \cgal\ does not
|
|
provide input operations for pretty printed data. By default a stream
|
|
is in {\sc ascii} mode.
|
|
|
|
\ccThree{IO::Mode}{set_mode(std::ios& s, IO::Mode m);}{}
|
|
|
|
\cgal\ provides the following functions to modify the mode of an IO stream.
|
|
|
|
\ccFunction{IO::Mode set_mode(std::ios& s, IO::Mode m);}{}
|
|
|
|
\ccFunction{IO::Mode set_ascii_mode(std::ios& s);}{}
|
|
\ccGlue
|
|
\ccFunction{IO::Mode set_binary_mode(std::ios& s);}{}
|
|
\ccGlue
|
|
\ccFunction{IO::Mode set_pretty_mode(std::ios& s);}{}
|
|
|
|
The following functions allow to test whether a stream is in a certain mode.
|
|
|
|
\ccFunction{IO::Mode get_mode(std::ios& s);}{}
|
|
|
|
\ccFunction{bool is_ascii(std::ios& s);}{}
|
|
\ccGlue
|
|
\ccFunction{bool is_binary(std::ios& s);}{}
|
|
\ccGlue
|
|
\ccFunction{bool is_pretty(std::ios& s);}{}
|
|
|
|
|
|
%\newpage
|
|
|
|
\ccThree{ostream&}{operator<<( const Class &c);}{}
|
|
|
|
%\begin{ccClass} {ostream}
|
|
\section{Output Operator}
|
|
%\ccCreationVariable{os}
|
|
|
|
%\ccDefinition
|
|
\cgal\ defines output operators for classes that are derived
|
|
from the class \ccStyle{ostream}. This allows to write to ostreams
|
|
as \ccStyle{cout} or \ccStyle{cerr}, as well as to strstreams
|
|
and fstreams.
|
|
The output operator is defined for all classes in the \cgal\ kernel and for the class \ccc{Color} as well.
|
|
Let \ccc{os} be an output stream.
|
|
|
|
\ccFunction{ostream& operator<<(ostream& os, Class c);}
|
|
{Inserts object \ccStyle{c} in the stream \ccc{os}. Returns \ccc{os}.}
|
|
|
|
|
|
\ccExample
|
|
|
|
\begin{cprog}
|
|
|
|
#include <CGAL/basic.h>
|
|
#include <iostream>
|
|
#include <fstream>
|
|
|
|
#include <CGAL/Cartesian.h>
|
|
#include <CGAL/Segment_2.h>
|
|
|
|
typedef CGAL::Point_2< CGAL::Cartesian<double> > Point;
|
|
typedef CGAL::Segment_2< CGAL::Cartesian<double> > Segment;
|
|
|
|
int main()
|
|
{
|
|
Point p(0,1), q(2,2);
|
|
Segment s(p,q);
|
|
|
|
CGAL::set_pretty_mode(std::cout);
|
|
std::cout << p << std::endl << q << std::endl;
|
|
|
|
std::ofstream f("data.txt");
|
|
CGAL::set_binary_mode(f);
|
|
f << s << p ;
|
|
|
|
return 1;
|
|
}
|
|
\end{cprog}
|
|
%\end{ccClass}
|
|
|
|
|
|
%\newpage
|
|
%\begin{ccClass} {istream}
|
|
\section{Input Operator}
|
|
|
|
|
|
%\ccDefinition
|
|
\cgal\ defines input operators for classes that are derived
|
|
from the class \ccStyle{istream}. This allows to read from istreams
|
|
as \ccStyle{cin}, as well as from strstreams and fstreams.
|
|
The input operator is defined for all classes in the \cgal\ kernel.
|
|
Let \ccc{is} be an input stream.
|
|
|
|
\ccFunction{istream& operator>>(istream& is, Class c);}
|
|
{Extracts object \ccStyle{c} from the stream \ccc{is}. Returns \ccc{is}.}
|
|
|
|
|
|
\ccExample
|
|
|
|
\begin{cprog}
|
|
|
|
#include <CGAL/basic.h>
|
|
#include <iostream>
|
|
#include <fstream>
|
|
|
|
#include <CGAL/Cartesian.h>
|
|
#include <CGAL/Segment_2.h>
|
|
|
|
typedef CGAL::Point_2< CGAL::Cartesian<double> > Point;
|
|
typedef CGAL::Segment_2< CGAL::Cartesian<double> > Segment;
|
|
|
|
int
|
|
main()
|
|
{
|
|
Point p, q;
|
|
Segment s;
|
|
|
|
CGAL::set_ascii_mode(std::cin);
|
|
std::cin >> p >> q;
|
|
|
|
std::ifstream f("data.txt");
|
|
CGAL::set_binary_mode(f);
|
|
f >> s >> p;
|
|
|
|
return 1;
|
|
}
|
|
\end{cprog}
|
|
%\end{ccClass}
|
|
|
|
|
|
|