NAME

         Imager::Transform - a library of register machine image transformations

SYNOPSIS

         # get a list of transformations
         my @funcs = Imager::Transform->list;
         # create a transformation object
         my $tran = Imager::Transform->new($name);
         # describe it
         print $tran->describe;
         # a list of constant names
         my @constants = $tran->constants;
         # information about some of the constants
         my @info = $tran->constants(@constants);

DESCRIPTION

       This module provides a library of transformations that use the Imager transform2()
       function.

       The aim is to provide a place to collect these transformations.

       At some point there might be an interface to add new functions, but there's not a whole
       lot of point to that.

       The interface is a little sparse as yet.

METHODS

       my @names = Imager::Transform->list
           Returns a list of the transformations.

       my $desc = Imager::Transform->describe($name);
       my $desc = $tran->describe()
           Describes a transformation specified either by name (as a class method) or by
           reference (as an instance method).

           The class method returns undef if there is no such transformation.

       my $tran = Imager::Transform->new($name)
           Create a new transformation object.  Returns undef if there is no such transformation.

       my @inputs = $tran->inputs;
       my $inputs = $tran->inputs;
           Returns a list of input image descriptions, or the number of them, depending on
           content.

           The list contains hash references, which current contain only one member, "desc", a
           description of the use of the input image.

       $tran->constants
           Returns a list of names of constants that can be set for the transformation.

       $tran->constants($name, $name, ...)
           Returns a hashref for each named constant, which contains the default in key "default"
           and a description in key "desc".

       my $out = $tran->transform(\%opts, \%constants, @imgs)
           Perform the image transformation.

           Returns the new image on success, or undef on failure, in which case you can use
           $tran->errstr to get an error message.

       $tran->errstr
           The error message, if any from the last image transformation.

BUGS

       Needs more transformations.

SEE ALSO

       Imager(3), transform.perl

AUTHOR

       Tony Cook <tonyc@cpan.org>