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NAME

LaTeX::TikZ - Perl object model for generating PGF/TikZ code.

VERSION

Version 0.03

SYNOPSIS

use LaTeX::TikZ;

# A couple of lines
my $hline = Tikz->line(-1 => 1);
my $vline = Tikz->line([ 0, -1 ] => [ 0, 1 ]);

# Paint them in red
$_->mod(Tikz->color('red')) for $hline, $vline;

# An octogon
use Math::Complex;
my $octo = Tikz->closed_polyline(
 map Math::Complex->emake(1, ($_ * pi)/4), 0 .. 7
);

# Only keep a portion of it
$octo->clip(Tikz->rectangle(-0.5*(1+i), 2*(1+i)));

# Fill it with dots
$octo->mod(Tikz->pattern(class => 'Dots'));

# Create a formatter object
my $tikz = Tikz->formatter(scale => 5);

# Put those objects all together and print them
my $seq = Tikz->seq($octo, $hline, $vline);
my ($head, $decl, $body) = $tikz->render($seq);
print "$_\n" for map @$_, $head, $decl, $body;

DESCRIPTION

This module provides an object model for TikZ, a graphical toolkit for LaTeX. It allows you to build structures representing geometrical figures, apply a wide set of modifiers on them, transform them globally with functors, and print them in the context of an existing TeX document.

CONCEPTS

Traditionally, in TikZ, there are two ways of grouping paths together :

  • either as a sequence, where each path is drawn in its own line :

    \draw (0cm,0cm) -- (0cm,1cm) ;
    \draw (0cm,0cm) -- (1cm,0cm) ;
  • or as an union, where paths are all drawn as one line :

    \draw (0cm,0cm) -- (0cm,1cm) (0cm,0cm) -- (1cm,0cm) ;

This distinction is important because there are some primitives that only apply to paths but not to sequences, and vice versa.

Figures are made of path or sequence sets assembled together in a tree.

Modifiers can be applied onto any set to alter the way in which it is generated. The two TikZ concepts of clips and layers have been unified with the modifiers.

INTERFACE

Containers

union

Tikz->union(@kids)

Creates a LaTeX::TikZ::Set::Union object out of the paths @kids.

# A path made of two circles
Tikz->union(
       Tikz->circle(0, 1),
       Tikz->circle(1, 1),
      )
    ->mod(
       Tikz->fill('red'),
       'even odd rule',
      );

path

Tikz->path(@kids)

A synonym for "union".

join

Tikz->join($connector, @kids)

Creates a LaTeX::TikZ::Set::Chain object that joins the paths @kinds with the given $connector which can be, according to "connector" in LaTeX::TikZ::Set::Chain, a string, an array reference or a code reference.

# A stair
Tikz->join('-|', map [ $_, $_ ], 0 .. 5);

chain

Tikz->chain($kid0, $link0, $kid1, $link1, ... $kidn)

Creates a LaTeX::TikZ::Set::Chain object that chains $kid0 to $kid1 with the string $link0, $kid1 to $kid2 with $link1, and so on.

# An heart-like shape
Tikz->chain([ 0, 1 ]
 => '.. controls (-1, 1.5)    and (-0.75, 0.25) ..' => [ 0, 0 ]
 => '.. controls (0.75, 0.25) and (1, 1.5)      ..' => [ 0, 1 ]
);

seq

Tikz->seq(@kids)

Creates a LaTeX::TikZ::Set::Sequence object out of the sequences or paths @kids.

my $bag = Tikz->seq($sequence, $path, $circle, $raw, $point);

Elements

Those are the building blocks of your geometrical figure.

point

Tikz->point($point)

Creates a LaTeX::TikZ::Set::Point object by coercing $point into a LaTeX::TikZ::Point. The following rules are available :

  • If $point isn't given, the point defaults to (0, 0).

    my $origin = Tikz->point;
  • If $point is a numish Perl scalar, it is treated as ($point, 0).

    my $unit = Tikz->point(1);
  • If two numish scalars $x and $y are given, they result in the point ($x, $y).

    my $one_plus_i = Tikz->point(1, 1);
  • If $point is an array reference, it is parsed as ($point->[0], $point->[1]).

    my $i = Tikz->point([ 0, 1 ]);
  • If $point is a Math::Complex object, the LaTeX::TikZ::Point::Math::Complex class is automatically loaded and the point is coerced into ($point->Re, $point->Im).

    my $j = Tikz->point(Math::Complex->emake(1, 2*pi/3));

You can define automatic coercions from your user point types to LaTeX::TikZ::Point by writing your own LaTeX::TikZ::Point::My::User::Point class. See LaTeX::TikZ::Meta::TypeConstraint::Autocoerce for the rationale and LaTeX::TikZ::Point::Math::Complex for an example.

line

Tikz->line($from => $to)

Creates a LaTeX::TikZ::Set::Line object between the points $from and $to.

my $x_axis = Tikz->line(-5 => 5);
my $y_axis = Tikz->line([ 0, -5 ] => [ 0, 5 ]);

polyline

Tikz->polyline(@points)

Creates a LaTeX::TikZ::Set::Polyline object that links the successive elements of @points by segments.

my $U = Tikz->polyline(
 Tikz->point(0, 1),
 Tikz->point(0, 0),
 Tikz->point(1, 0),
 Tikz->point(1, 1),
);

closed_polyline

Tikz->closed_polyline(@points)

Creates a LaTeX::TikZ::Set::Polyline object that cycles through successive elements of @points.

my $diamond = Tikz->closed_polyline(
 Tikz->point(0, 1),
 Tikz->point(-1, 0),
 Tikz->point(0, -2),
 Tikz->point(1, 0),
);

rectangle

Tikz->rectangle($from => $to)
Tikz->rectangle($from => { width => $width, height => $height })

Creates a LaTeX::TikZ::Set::Rectangle object with opposite corners $from and $to, or with anchor point $from and dimensions $width and $height.

my $square = Tikz->rectangle(
 Tikz->point,
 Tikz->point(2, 1),
);

circle

Tikz->circle($center, $radius)

Creates a LaTeX::TikZ::Set::Circle object of center $center and radius $radius.

my $unit_circle = Tikz->circle(0, 1);

arc

Tikz->arc($from => $to, $center)

Creates a LaTeX::TikZ::Set structure that represents an arc going from $from to $to with center $center.

# An arc. The points are automatically coerced into LaTeX::TikZ::Set::Point objects
my $quarter = Tikz->arc(
 [ 1, 0 ] => [ 0, 1 ],
 [ 0, 0 ]
);

arrow

Tikz->arrow($from => $to)
Tikz->arrow($from => dir => $dir)

Creates a LaTeX::TikZ::Set structure that represents an arrow going from $from towards $to, or starting at $from in direction $dir.

# An horizontal arrow
my $arrow = Tikz->arrow(0 => 1);

raw

Tikz->raw($content)

Creates a LaTeX::TikZ::Set::Raw object that will instantiate to the raw TikZ code $content.

Modifiers

Modifiers are applied onto sets by calling the ->mod method, like in $set->mod($mod). This method returns the $set object, so it can be chained.

clip

Tikz->clip($path)

Creates a LaTeX::TikZ::Mod::Clip object that can be used to clip a given sequence by the (closed) path $path.

my $box = Tikz->clip(
 Tikz->rectangle(0 => [ 1, 1 ]),
);

Clips can also be directly applied to sets with the ->clip method.

my $set = Tikz->circle(0, 1.5)
              ->clip(Tikz->rectangle([-1, -1] => [1, 1]));

layer

Tikz->layer($name, above => \@above, below => \@below)

Creates a LaTeX::TikZ::Mod::Layer object with name $name and optional relative positions @above and @below.

my $layer = Tikz->layer(
 'top'
 above => [ 'main' ],
);

The default layer is main.

Layers are stored into a global hash, so that when you refer to them by their name, you get the existing layer object.

Layers can also be directly applied to sets with the ->layer method.

my $dots = Tikz->rectangle(0 => [ 1, 1 ])
               ->mod(Tikz->pattern(class => 'Dots'))
               ->layer('top');

scale

Tikz->scale($factor)

Creates a LaTeX::TikZ::Mod::Scale object that scales the sets onto which it apply by the given $factor.

my $circle_of_radius_2 = Tikz->circle(0 => 1)
                             ->mod(Tikz->scale(2));

width

Tikz->width($line_width)

Creates a LaTeX::TikZ::Mod::Width object that sets the line width to $line_width when applied.

my $thick_arrow = Tikz->arrow(0 => 1)
                      ->mod(Tikz->width(5));

color

Tikz->color($color)

Creates a LaTeX::TikZ::Mod::Color object that sets the line color to $color (given in the xcolor syntax).

# Paint the previous $thick_arrow in red.
$thick_arrow->mod(Tikz->color('red'));

fill

Tikz->fill($color)

Creates a LaTeX::TikZ::Mod::Fill object that fills the interior of a path with the solid color $color (given in the xcolor syntax).

my $red_box = Tikz->rectangle(0 => { width => 1, height => 1 })
                  ->mod(Tikz->fill('red'));

pattern

Tikz->pattern(class => $class, %args)

Creates a LaTeX::TikZ::Mod::Pattern object of class $class and arguments %args that fills the interior of a path with the specified pattern. $class is prepended with LaTeX::TikZ::Mod::Pattern when it doesn't contain ::. See LaTeX::TikZ::Mod::Pattern::Dots and LaTeX::TikZ::Mod::Pattern::Lines for two examples of pattern classes.

my $hatched_circle = Tikz->circle(0 => 1)
                         ->mod(Tikz->pattern(class => 'Lines'));

raw_mod

Tikz->raw_mod($content)

Creates a LaTeX::TikZ::Mod::Raw object that will instantiate to the raw TikZ mod code $content.

my $homemade_arrow = Tikz->line(0 => 1)
                         ->mod(Tikz->raw_mod('->')) # or just ->mod('->')

Helpers

formatter

Tikz->formatter(%args)

Creates a LaTeX::TikZ::Formatter object that can render a LaTeX::TikZ::Set tree.

my $tikz = Tikz->formatter;
my ($header, $declarations, $seq1_body, $seq2_body) = $tikz->render($set1, $set2);

functor

Tikz->functor(@rules)

Creates a LaTeX::TikZ::Functor anonymous subroutine that can be called against LaTeX::TikZ::Set trees to clone them according to the given rules. @rules should be a list of array references whose first element is the class/role to match against and the second the handler to execute.

# The default is a clone method
my $clone = Tikz->functor;
my $dup = $set->$clone;

# A translator
my $translate = Tikz->functor(
 'LaTeX::TikZ::Set::Point' => sub {
  my ($functor, $set, $x, $y) = @_;

  $set->new(
   point => [
    $set->x + $x,
    $set->y + $y,
   ],
   label => $set->label,
   pos   => $set->pos,
  );
 },
);
my $shifted = $set->$translate(1, 1);

# A mod stripper
my $strip = Tikz->functor(
 '+LaTeX::TikZ::Mod' => sub { return },
);
my $naked = $set->$strip;

DEPENDENCIES

Mouse 0.80 or greater.

Sub::Name.

Math::Complex, Math::Trig.

Scalar::Util, List::Util, Task::Weaken.

SEE ALSO

PGF/TikZ - http://pgf.sourceforge.net.

AUTHOR

Vincent Pit, <perl at profvince.com>, http://www.profvince.com.

You can contact me by mail or on irc.perl.org (vincent).

BUGS

Please report any bugs or feature requests to bug-latex-tikz at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=LaTeX-TikZ. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

perldoc LaTeX::TikZ

COPYRIGHT & LICENSE

Copyright 2010,2011,2012,2013,2014,2015 Vincent Pit, all rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.