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NAME

SVG::TT::Graph - Base object for generating SVG Graphs

SYNOPSIS

  package SVG::TT::Graph::GRAPH_TYPE
  use SVG::TT::Graph;
  use base qw(SVG::TT::Graph);
  use vars qw($VERSION);
  $VERSION = $SVG::TT::Graph::VERSION;
  $TEMPLATE_FH = \*DATA;

  sub _set_defaults {
    my $self = shift;

    my %default = (
        'keys'  => 'value',
    );
    while( my ($key,$value) = each %default ) {
      $self->{config}->{$key} = $value;
    }
  }

  
  # optional - called when object is created
  sub _init {
    my $self = shift;
  # any testing you want to do.
  
  }

  ...
  
  1;
  __DATA__
  <!-- SVG Template goes here  -->


  In your script:
  
  use SVG::TT::Graph::GRAPH_TYPE;
  
  my $width = '500',
  my $heigh = '300',
  my @fields = qw(field_1 field_2 field_3);
  
  my $graph = SVG::TT::Graph::GRAPH_TYPE->new({
    # Required for some graph types
    'fields'           => \@fields,
    # .. other config options
    'height' => '500',
  });
  
  my @data = qw(23 56 32);
  $graph->add_data({
    'data' => \@data,
    'title' => 'Sales 2002',
  });
  
  # find a config options value
  my $config_value = $graph->config_option();
  # set a config option value
  $graph->config_option($config_value);
  
  # All graphs support SVGZ (compressed SVG) if 
  # Compress::Zlib is available. Use either the
  # 'compress' => 1 config option, or:
  $graph->compress(1);

  # All graph SVGs can be tidied if XML::Tidy
  # is installed. Use either the 'tidy' => 1
  # config option, or:
  $graph->tidy(1);

  print "Content-type: image/svg+xml\n\n";
  print $graph->burn();

DESCRIPTION

This package should be used as a base for creating SVG graphs. If XML::Tidy is installed, the SVG files generated are tidied.

See SVG::TT::Graph::Line for an example.

METHODS

add_data()

  my @data_sales_02 = qw(12 45 21);

  $graph->add_data({
    'data' => \@data_sales_02,
    'title' => 'Sales 2002',
  });

This method allows you do add data to the graph object. It can be called several times to add more data sets in.

clear_data()

  my $graph->clear_data();

This method removes all data from the object so that you can reuse it to create a new graph but with the same config options.

get_template()

  print $graph->get_template();

This method returns the TT template used for making the graph.

burn()

  print $graph->burn();

This method processes the template with the data and config which has been set and returns the resulting SVG.

This method will croak unless at least one data set has been added to the graph object.

compress()

  $graph->compress(1);

If Compress::Zlib is installed, the content of the SVG file can be compressed. This get/set method controls whether or not to compress. The default is 0 (off).

tidy()

  $graph->tidy(1);

If XML::Tidy is installed, the content of the SVG file can be formatted in a prettier way. This get/set method controls whether or not to tidy. The default is 0 (off). The limitations of tidy are described at this URL: http://search.cpan.org/~pip/XML-Tidy-1.12.B55J2qn/Tidy.pm#tidy%28%29

config methods

  my $value = $graph->method();
  $graph->method($value);

This object provides autoload methods for all config options defined in the _set_default method within the inheriting object.

See the SVG::TT::Graph::GRAPH_TYPE documentation for a list.

EXAMPLES

For examples look at the project home page http://leo.cuckoo.org/projects/SVG-TT-Graph/

EXPORT

None by default.

ACKNOWLEDGEMENTS

Thanks to Foxtons for letting us put this on CPAN. Todd Caine for heads up on reparsing the template (but not using atm) David Meibusch for TimeSeries and a load of other ideas Thanks for all the patches supplied by Andrew Ruthven and others

AUTHOR

Leo Lapworth (LLAP@cuckoo.org) and Stephen Morgan (TT and SVG)

SEE ALSO

SVG::TT::Graph::Line, SVG::TT::Graph::Bar, SVG::TT::Graph::BarHorizontal, SVG::TT::Graph::BarLine, SVG::TT::Graph::Pie, SVG::TT::Graph::TimeSeries, Compress::Zlib, XML::Tidy

COPYRIGHT AND LICENSE

Copyright (C) 2003, Leo Lapworth

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