new()

  use SVG::TT::Graph::Pie;
  # Field names along the X axis
  my @fields = qw(Jan Feb Mar);
  my $graph = SVG::TT::Graph::Pie->new({
    # Required
    'fields'                  => \@fields,
    # Optional - defaults shown
    'height'                  => '500',
    'width'                   => '300',
    'show_graph_title'        => 0,
    'graph_title'             => 'Graph Title',
    'show_graph_subtitle'     => 0,
    'graph_subtitle'          => 'Graph Sub Title',
    'show_shadow'             => 1,
    'shadow_size'             => 1,
    'shadow_offset'           => 15,
    'key_placement'           => 'R',
    # data by pie chart wedges:
    'show_data_labels'        => 0,
    'show_actual_values'      => 0,
    'show_percent'            => 1,
    'rollover_values'         => 0,
    'show_path_title'         => 0,
    'show_title_fields'       => 0,
    # data on key:
    'show_key_data_labels'    => 1,
    'show_key_actual_values'  => 1,
    'show_key_percent'        => 0,
    'expanded'                => 0,
    'expand_greatest'         => 0,
    # Stylesheet defaults
    'style_sheet'             => '/includes/graph.css', # internal stylesheet
    'style_sheet_field_names' => 0,
    'random_colors'           => 0,
  });

The constructor takes a hash reference, fields (the name for each slice on the pie) MUST be set, all other values are defaulted to those shown above - with the exception of style_sheet which defaults to using the internal style sheet.

add_data()

  my @data_sales_02 = qw(12 45 21);
  $graph->add_data({
    'data' => \@data_sales_02,
    'title' => 'Sales 2002',
  });

This method allows you to add data to the graph object, only the first data set added will be used!

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.

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.

config methods

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

The following is a list of the methods which are available to change the config of the graph object after it has been created.

height()

Set the height of the graph box, this is the total height of the SVG box created - not the graph it self which auto scales to fix the space.

width()

Set the width of the graph box, this is the total width of the SVG box created - not the graph it self which auto scales to fix the space.

compress()

Whether or not to compress the content of the SVG file (Compress::Zlib required).

tidy()

Whether or not to tidy the content of the SVG file (XML::Tidy required).

style_sheet()

Set the path to an external stylesheet, set to '' if you want to revert back to using the defaut internal version.

Set to "inline:<style>...</style>" with your CSS in between the tags. You can thus override the default style without requireing an external URL.

The default stylesheet handles up to 12 data sets. All data series over the 12th will have no style and be in black. If you have over 12 data sets you can assign them all random colors (see the random_color() method) or create your own stylesheet and add the additional settings for the extra data sets.

To create an external stylesheet create a graph using the default internal version and copy the stylesheet section to an external file and edit from there.

random_colors()

Use random colors in the internal stylesheet

style_sheet_field_names()

If you use the style_sheet_field_names() option then you can use the field names within your stylesheet. This allows consistent use of styles. The names should be:

show_graph_title()

Whether to show a title on the graph, default is '0'.

graph_title()

What the title on the graph should be.

show_graph_subtitle()

Whether to show a subtitle on the graph, default is '0'.

graph_subtitle()

What the subtitle on the graph should be.

show_shadow()

Turn the shadow on and off, default to '1', set to '0' if you don't want it. It is automatically turned off if you extract one section of the pie.

shadow_size()

Size of the shadow if shown, measured as percentage of pie chart radius, default of 1 being the same size as the pie.

shadow_offset()

Offset (in pixels) of shadow to bottom-right in relation to the center of the pie chart.

key()

Whether to show a key, defaults to 0, set to '1' if you want to show it.

key_placement()

Defaults to 'R' - right, can be 'R', 'L', 'T' or 'B'.

show_data_labels()

Show label on pie chart, defaults to '0', can be set to '1'.

show_actual_values()

Show values on pie chart, defaults to '0', can be set to '1'.

show_percent()

Show percent (rounded) on the pie chart, defaults to '1', can be set to '0'.

rollover_values()

Shows data field and value when the mouse is over a piechart wedge.

show_path_title()

Whether to add the title attribute to the data path tags, which will show "tooltips" when hovering over the bar area.

show_title_fields()

Whether to show field values as title elements in path tag, defaults to 0, set to '1' to turn on. Suggest on single add_data graphs, for overlapping graphs leave off to see the title value used in the add_data call.

show_key_data_labels()

Show label on the key, defaults to '1', can be set to '0'.

show_key_actual_values()

Show value on the key, defaults to '1', can be set to '0'.

show_key_percent()

Show percent (rounded) on the key, defaults to '0', can be set to '1'.

expanded()

All slices of pie are exploded out, defaults to '0'. Do not set to '1' if you are going to use expanded_greatest().

expand_greatest()

The largest slice of pie is exploded out from the pie, defaults to '0'. Useful if you are only showing the percentages (which are rounded) but still want to visually show which slice was largest.

Do not set to '1' if you are going to use expanded().