Flavio Poletti

NAME

Graphics::Potrace - bindings to the potrace library

VERSION

version 0.76

SYNOPSIS

   # Step by step
   use Graphics::Potrace qw< raster >;
   my $raster = raster('
   ..........................
   .......XXXXXXXXXXXXXXX....
   ..XXXXXXXX.......XXXXXXX..
   ....XXXXX.........XXXXXX..
   ......XXXXXXXXXXXXXXX.....
   ...XXXXXX........XXXXXXX..
   ...XXXXXX........XXXXXXX..
   ....XXXXXXXXXXXXXXXXXX....
   ..........................
   ');
   my $vector = $raster->trace();
   $vector->export(Svg => file => 'example.svg');
   $vector->export(Svg => file => \my $svg_dump);
   $vector->export(Svg => fh   => \*STDOUT);

   # There is a simpler way to get a dump in a scalar
   my $eps_dump = $vector->render('Eps');

   # All in one facility
   use Graphics::Potrace qw< trace >;
   trace(
      raster => '
      ..........................
      .......XXXXXXXXXXXXXXX....
      ..XXXXXXXX.......XXXXXXX..
      ....XXXXX.........XXXXXX..
      ......XXXXXXXXXXXXXXX.....
      ...XXXXXX........XXXXXXX..
      ...XXXXXX........XXXXXXX..
      ....XXXXXXXXXXXXXXXXXX....
      ..........................
      ',
      vectorial => [ Svg => file => 'example.svg' ],
   );

   # There is a whole lot of DWIMmery in both raster() and trace().
   # Stick to Graphics::Potrace::Raster for finer control
   use Graphics::Potrace::Raster;
   my $raster = Graphics::Potrace::Raster->load(
      Ascii => text => '
      ..........................
      .......XXXXXXXXXXXXXXX....
      ..XXXXXXXX.......XXXXXXX..
      ....XXXXX.........XXXXXX..
      ......XXXXXXXXXXXXXXX.....
      ...XXXXXX........XXXXXXX..
      ...XXXXXX........XXXXXXX..
      ....XXXXXXXXXXXXXXXXXX....
      ..........................
      ',
   );
   # you know what to do with $raster - see above!

DESCRIPTION

Potrace (http://potrace.sourceforge.net/) is a program (and a library) by Peter Selinger for Transforming bitmaps into vector graphics. This distribution aims at binding the library from Perl for your fun and convenience.

INTERFACE

raster

   my $raster = raster(@parameters);

Generate a Graphics::Potrace::Raster object for further usage.

If the first parameter you provide is already such an object, it is returned back. This lets you forget about what you actually have, and it might be handy.

Otherwise, a new Graphics::Potrace::Raster object is created, and "dwim_load" in Graphics::Potrace::Raster is called upon it passing the provided parameters. This applies an heuristic to give you something reasonable, see there for details.

raster2vectorial

   my $vector = raster2vectorial($raster, %parameters);
   my $vector = raster2vectorial($raster, \%parameters);

Arguments:

$raster

a Graphics::Potrace::Raster object, or anything that has a packed() method programmed to return the right hash ref.

%parameters
$parameters

parameters for tracing. This version of the bindings is aligned with libpotrace 1.10 and supports the following parameters:

  • turdsize

  • turnpolicy

  • opticurve

  • alphamax

  • opttolerance

See e.g. http://potrace.sourceforge.net/potracelib.pdf for details.

You should never actually need this function, because you can just as well call:

   my $vector = $raster->trace(%parameters); # or with \%parameters

unless $raster isn't actually a Graphics::Potrace::Raster object and you managed to duck a packed() method in it.

trace

   my $vector = trace(%parameters);
   my $vector = trace($parameters);

This is the most Do What I Mean (a.k.a. DWIM) function of the whole distribution. It tries to be as bloated as it can, but to provide you a single interface for your one-off needs.

The following arguments can be provided either via %parameters or through an input hash ref:

raster

the raster to load. This parameter is used to call "raster" above, see there and "dwim_load" in Graphics::Potrace::Raster for in-depth documentation. And yes, if you already have a Graphics::Potrace::Raster object you can pass it in.

This parameter is mandatory.

vectorial

a description of what you want to do with the vector, e.g. export it or get a representation. If present, this parameter is expected to be an array reference containing parameters for "export" in Graphics::Potrace::Vectorial, see there for details.

This parameter is optional.

all Potrace parameters supported by "raster2trace"

these parameters will be passed over to raster2trace, they are all optional.

Any other parameter will be ignored.

version

This function returns the version of the Potrace library.

SEE ALSO

See http://potrace.sourceforge.net/ for Potrace - it's awesome!

AUTHOR

Flavio Poletti <polettix@cpan.org>

COPYRIGHT AND LICENSE

Copyright (C) 2011-2015 by Flavio Poletti polettix@cpan.org.

This module is free software. You can redistribute it and/or modify it under the terms of the Artistic License 2.0.

This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.