CGAL::Geomview_stream Class Reference

#include <CGAL/IO/Geomview_stream.h>

Definition

An object of the class Geomview_stream is a stream in which geometric objects can be inserted and where geometric objects can be extracted from.

The constructor starts Geomview either on the local either on a remote machine.

Implementation

The constructor forks a process and establishes two pipes between the processes. The forked process is then overlaid with Geomview. The file descriptors stdin and stdout of Geomview are hooked on the two pipes.

All insert operators construct expressions in gcl, the Geomview command language, which is a subset of Lisp. These expressions are sent to Geomview via the pipe. The extract operators notify interest for a certain kind of events. When such an event happens Geomview sends a description of the event in gcl and the extract operator has to parse this expression.

In order to implement further insert and extract operators you should take a look at the implementation and at the Geomview manual.

Examples:

Geomview/gv_terrain.cpp.

Public Member Functions
template<class InputIterator >
void	draw_triangles (InputIterator begin, InputIterator end)
	[begin;end) is an iterator range with value type Triangle_3<R>. More...

Related Functions
(Note that these are not member functions.)
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Point_2< R > &p)
	Inserts the point p into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Point_3< R > &p)
	Inserts the point p into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Segment_2< R > &s)
	Inserts the segment s into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Segment_3< R > &s)
	Inserts the segment s into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Ray_2< R > &r)
	Inserts the ray r into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Ray_3< R > &r)
	Inserts the ray r into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Line_2< R > &l)
	Inserts the line l into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Line_3< R > &l)
	Inserts the line l into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Triangle_2< R > &t)
	Inserts the triangle t into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Triangle_3< R > &t)
	Inserts the triangle t into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Tetrahedron_3< R > &t)
	Inserts the tetrahedron t into the stream gs.
template<class R >
Geomview_stream &	operator<< (Geomview_stream &gs, const Sphere_3< R > &s)
	Inserts the sphere s into the stream gs.
Geomview_stream &	operator<< (Geomview_stream &gs, const Bbox_2 &b)
	Inserts the bounding box b into the stream gs.
Geomview_stream &	operator<< (Geomview_stream &gs, const Bbox_3 &b)
	Inserts the bounding box b into the stream gs.
template<class R >
Geomview_stream &	operator>> (Geomview_stream &gs, Point_3< R > &p)
	Extracts the point p from the stream gs. More...
template<class Traits , class HDS >
Geomview_stream &	operator<< (Geomview_stream &G, const Polyhedron_3< Traits, HDS > &P)
	Inserts the polyhedron P into the stream gs. More...
template<class GT , class TDS >
Geomview_stream &	operator<< (Geomview_stream &G, const Triangulation_2< GT, TDS > &T)
	Inserts the 2D triangulation T into the stream gs. More...
template<class GT , class TDS >
Geomview_stream &	operator<< (Geomview_stream &G, const Triangulation_3< GT, TDS > &T)
	Inserts the 3D triangulation T into the stream gs. More...

Creation
	Geomview_stream (const Bbox_3 &bbox=Bbox_3(0, 0, 0, 1, 1, 1), const char *machine=nullptr, const char *login=nullptr)
	Introduces a Geomview stream gs with a camera that sees the bounding box. More...

Colors
Geomview_stream &	operator<< (const Color &c)
	Geomview distinguishes between edge and face colors. More...
Color	set_bg_color (const Color &c)
	Changes the background color. More...
Color	set_vertex_color (const Color &c)
	Changes the vertex color. More...
Color	set_edge_color (const Color &c)
	Changes the edge color. More...
Color	set_face_color (const Color &c)
	Changes the face color. More...

Miscellaneous
void	clear ()
	Deletes all objects.
void	pickplane ()
	Creates a pickplane (useful after a clear).
void	look_recenter ()
	Positions the camera in a way that all objects can be seen.
int	get_line_width () const
	Returns the line width.
int	set_line_width (int w)
	Sets the line width to w. More...
double	get_vertex_radius () const
	Returns the radius of vertices.
double	set_vertex_radius (double r) const
	Sets the radius of vertices to d. More...
string	get_new_id (string s)
	Used to obtain unique identifier names passed to Geomview. More...
bool	set_wired (bool b)
	Sets wired mode. More...
bool	get_wired ()
	Returns true iff wired mode is on.

Advanced and Developers Features
The following functions are helpful if you develop your own insert and extract functions. The following functions allow to pass a string from Geomview and to read data sent back by Geomview.
Geomview_stream &	operator<< (string s)
	Inserts string s into the stream.
Geomview_stream &	operator>> (char *s)
	Extracts a string s from the stream. More...
Geomview_stream &	operator<< (int i)
	Inserts i into the stream. More...
Geomview_stream &	operator<< (unsigned int i)
	Inserts i into the stream. More...
Geomview_stream &	operator<< (long i)
	Inserts i into the stream. More...
Geomview_stream &	operator<< (unsigned long i)
	Inserts i into the stream. More...
Geomview_stream &	operator<< (double d)
	Inserts double d into the stream. More...
bool	set_trace (bool b)
	Sets tracing on. More...
bool	get_trace ()
	Returns true iff tracing is on.
bool	set_raw (bool b)
	Sets raw mode. More...
bool	get_raw ()
	Returns true iff raw mode is on.
bool	set_echo (bool b)
	Sets echo mode. More...
bool	get_echo ()
	Returns true iff echo mode is on.
bool	set_binary_mode (bool b=true)
	Sets whether we are in binary mode.
bool	set_ascii_mode (bool b=true)
	Sets whether we are in ascii mode.
bool	get_binary_mode ()
	Returns true iff gs is in binary mode.
bool	get_ascii_mode ()
	Returns true iff gs is in ascii mode.

Constructor & Destructor Documentation

Geomview_stream()

CGAL::Geomview_stream::Geomview_stream	(	const Bbox_3 &	bbox = Bbox_3(0, 0, 0, 1, 1, 1),
		const char *	machine = nullptr,
		const char *	login = nullptr
	)

Introduces a Geomview stream gs with a camera that sees the bounding box.

The command geomview must be in the user's PATH. If machine and login are not nullptr, Geomview is started on the remote machine using rsh.

Member Function Documentation

draw_triangles()

template<class InputIterator >

void CGAL::Geomview_stream::draw_triangles	(	InputIterator	begin,
		InputIterator	end
	)

[begin;end) is an iterator range with value type Triangle_3<R>.

This method uses the OFF format to draw several triangles at once, which is much faster than drawing them one by one.

get_new_id()

string CGAL::Geomview_stream::get_new_id

(

string

s

)

Used to obtain unique identifier names passed to Geomview.

On successive calls with the same s value, it will return a string which is s appended with the numbers 0, then 1, then 2... Note that all counters are reset when clear() is called.

operator[1/6]

Geomview_stream& CGAL::Geomview_stream::operator<<

(

const Color &

c

)

Geomview distinguishes between edge and face colors.

The edge color is at the same time the color of vertices.

Makes c the color of vertices, edges and faces in subsequent IO operations.

operator[2/6]

Geomview_stream& CGAL::Geomview_stream::operator<<

(

int

i

)

Inserts i into the stream.

Puts whitespace around if the stream is in ascii mode.

operator[3/6]

Geomview_stream& CGAL::Geomview_stream::operator<<

(

unsigned int

i

)

Inserts i into the stream.

Puts whitespace around if the stream is in ascii mode.

operator[4/6]

Geomview_stream& CGAL::Geomview_stream::operator<<

(

long

i

)

Inserts i into the stream.

Puts whitespace around if the stream is in ascii mode. Currently implemented by converting to int, so it can be truncated on 64 bit platforms.

operator[5/6]

Geomview_stream& CGAL::Geomview_stream::operator<<

(

unsigned long

i

)

Inserts i into the stream.

Puts whitespace around if the stream is in ascii mode. Currently implemented by converting to unsigned int, so it can be truncated on 64 bit platforms.

operator[6/6]

Geomview_stream& CGAL::Geomview_stream::operator<<

(

double

d

)

Inserts double d into the stream.

Puts whitespace around if the stream is in ascii mode.

operator>>()

Geomview_stream& CGAL::Geomview_stream::operator>>

(

char *

s

)

Extracts a string s from the stream.

Precondition

You have to allocate enough memory.

set_bg_color()

Color CGAL::Geomview_stream::set_bg_color

(

const Color &

c

)

Changes the background color.

Returns the old value.

Examples:

Geomview/gv_terrain.cpp.

set_echo()

bool CGAL::Geomview_stream::set_echo

(

bool

b

)

Sets echo mode.

In echo mode, when you select a point in Geomview, the point is actually sent back to Geomview. Returns the previous value. By default, echo mode is on.

set_edge_color()

Color CGAL::Geomview_stream::set_edge_color

(

const Color &

c

)

Changes the edge color.

Returns the old value.

set_face_color()

Color CGAL::Geomview_stream::set_face_color

(

const Color &

c

)

Changes the face color.

Returns the old value.

set_line_width()

int CGAL::Geomview_stream::set_line_width

(

int

w

)

Sets the line width to w.

Returns the previous value.

Examples:

Geomview/gv_terrain.cpp.

set_raw()

bool CGAL::Geomview_stream::set_raw

(

bool

b

)

Sets raw mode.

In raw mode, kernel points are output without headers and footers, just the coordinates (in binary or ascii mode). This allows the implementation of the stream functions for other objects to re-use the code for points internally, by temporary saving the raw mode to true, and restoring it after. Returns the previous value. By default, raw mode is off.

set_trace()

bool CGAL::Geomview_stream::set_trace

(

bool

b

)

Sets tracing on.

The data that are sent to Geomview are also sent to cerr. Returns the previous value. By default tracing is off.

set_vertex_color()

Color CGAL::Geomview_stream::set_vertex_color

(

const Color &

c

)

Changes the vertex color.

Returns the old value.

set_vertex_radius()

double CGAL::Geomview_stream::set_vertex_radius

(

double

r

)

const

Sets the radius of vertices to d.

Returns the previous value.

set_wired()

bool CGAL::Geomview_stream::set_wired

(

bool

b

)

Sets wired mode.

In wired mode, some structures output only there edges, not there surfaces. Returns the previous value. By default, wired mode is off.

Examples:

Geomview/gv_terrain.cpp.