# NAME

Chart::Clicker - Powerful, extensible charting.

# VERSION

version 2.76

# SYNOPSIS

  use Chart::Clicker;

  my $cc = Chart::Clicker->new;

  my @values = (42, 25, 86, 23, 2, 19, 103, 12, 54, 9);
  $cc->add_data('Sales', \@values);

  # alternately, you can add data one bit at a time...
  foreach my $v (@values) {
    $cc->add_data('Sales', $v);
  }

  # Or, if you want to specify the keys you can use a hashref
  my $data = { 12 => 123, 13 => 341, 14 => 1241 };
  $cc->add_data('Sales', $data);

  $cc->write_output('foo.png');

# DESCRIPTION

Chart::Clicker aims to be a powerful, extensible charting package that creates
really pretty output.  Charts can be saved in png, svg, pdf and postscript
format.

Clicker leverages the power of Graphics::Primitive to create snazzy graphics
without being tied to specific backend.  You may want to begin with
[Chart::Clicker::Tutorial](http://search.cpan.org/perldoc?Chart::Clicker::Tutorial).

# EXAMPLES

For code examples see the examples repository on GitHub:
[http://github.com/gphat/chart-clicker-examples/](http://github.com/gphat/chart-clicker-examples/)

# FEATURES

## Renderers

Clicker supports the following renderers:

- __Line__
- __StackedLine__
- __Bar__
- __StackedBar__
- __Area__
- __StackedArea__
- __Bubble__
- __CandleStick__
- __Point__
- __Pie__
- __PolarArea__

# ADDING DATA

The synopsis shows the simple way to add data.

  my @values = (42, 25, 86, 23, 2, 19, 103, 12, 54, 9);
  foreach my $v (@values) {
    $cc->add_data('Sales', $v);
  }

This is a convenience method provided to make simple cases much simpler. Adding
multiple Series to a chart is as easy as changing the name argument of
`add_data`.  Each unique first argument will result in a separate series. See
the docs for `add_data` to learn more.

If you'd like to use the more advanced features of Clicker you'll need to
shake off this simple method and build Series & DataSets explicitly.

  use Chart::Clicker::Data::Series;
  use Chart::Clicker::Data::DataSet;

  ...

  my $series = Chart::Clicker::Data::Series->new(
    keys    => [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ],
    values  => [ 42, 25, 86, 23, 2, 19, 103, 12, 54, 9 ],
  );

  my $ds = Chart::Clicker::Data::DataSet->new(series => [ $series ]);

  $cc->add_to_datasets($ds);

This used to be the only way to add data, but repeated requests to make the
common case easier resulted in the inclusion of `add_data`.

# CONTEXTS

The normal use case for a chart is a couple of datasets on the same axes.
Sometimes you want to chart one or more datasets on different axes.  A common
need for this is when you are comparing two datasets of vastly different scale
such as the number of employees in an office (1-10) to monthly revenues (10s
of thousands).  On a normal chart the number of employees would show up as a
flat line at the bottom of the chart.

To correct this, Clicker has contexts.  A context is a pair of axes, a
renderer and a name.  The name is the 'key' by which you will refer to the
context.

  my $context = Chart::Clicker::Context->new( name => 'sales' );
  $clicker->add_to_contexts($context);

  $dataset->context('sales');

  $clicker->add_to_datasets($dataset);

New contexts provide a fresh domain and range axis and default to a Line
renderer.

__Caveat__: Clicker expects that the default context (identified by the string
"default") will always be present.  It is from this context that some of
Clicker's internals draw their values.  You should use the default context
unless you need more than one, in which case you should use "default" as the
base context.

# FORMATS & OUTPUT

Clicker supports PNG, SVG, PDF and PostScript output.  To change your output
type, specificy it when you create your Clicker object:

  my $cc = Chart::Clicker->new(format => 'pdf', ...);
  # ...
  $cc->write_output('chart.pdf');

If you are looking to get a scalar of the output for use with HTTP or
similar things, you can use:

  # ... make your chart
  $cc->draw;
  my $image_data = $cc->rendered_data;

If you happen to be using Catalyst then take a look at
[Catalyst::View::Graphics::Primitive](http://search.cpan.org/perldoc?Catalyst::View::Graphics::Primitive).

# ATTRIBUTES

## background_color

Set/Get the background color.  Expects a [Graphics::Color](http://search.cpan.org/perldoc?Graphics::Color) object.  Defaults
to white.

## border

Set/Get the border.  Expects a [Graphics::Primitive::Border](http://search.cpan.org/perldoc?Graphics::Primitive::Border).

## color_allocator

Set/Get the color_allocator for this chart.

## contexts

Set/Get the contexts for this chart.

## datasets

Get/Set the datasets for this chart.

## driver

Set/Get the driver used to render this Chart. Defautls to
[Graphics::Primitive::Driver::Cairo](http://search.cpan.org/perldoc?Graphics::Primitive::Driver::Cairo).

## format

Get the format for this Chart.  Required in the constructor.  Must be on of
Png, Pdf, Ps or Svg.

## grid_over

Flag controlling if the grid is rendered __over__ the data.  Defaults to 0.
You probably want to set the grid's background color to an alpha of 0 if you
enable this flag.

## height

Set/Get the height.  Defaults to 300.

## layout_manager

Set/Get the layout manager.  Defaults to [Layout::Manager::Compass](http://search.cpan.org/perldoc?Layout::Manager::Compass).

## legend

Set/Get the legend that will be used with this chart.

## legend_position

The position the legend will be added.  Should be one of north, south, east,
west or center as required by [Layout::Manager::Compass](http://search.cpan.org/perldoc?Layout::Manager::Compass).

## marker_overlay

Set/Get the marker overlay object that will be used if this chart
has markers.  This is lazily constructed to save time.

## over_decorations

Set/Get an arrayref of "over decorations", or things that are drawn OVER the
chart.  This is an advanced feature.  See `overaxis-bar.pl` in the examples.

## padding

Set/Get the padding.  Expects a [Graphics::Primitive::Insets](http://search.cpan.org/perldoc?Graphics::Primitive::Insets) object.  Defaults
to 3px on all sides.

## plot

Set/Get the Plot on which things are drawn.

## subgraphs

You can add "child" graphs to this one via `add_subgraph`.  These must be
Chart::Clicker objects and they will be added to the bottom of the existing
chart.  This is a rather esoteric feature.

## title

Set/Get the title component for this chart.  This is a
[Graphics::Primitive::TextBox](http://search.cpan.org/perldoc?Graphics::Primitive::TextBox), not a string.  To set the title of a chart
you should access the TextBox's `text` method.

  $cc->title->text('A Title!');
  $cc->title->font->size(20);
  # etc, etc

If the title has text then it is added to the chart in the position specified
by `title_position`.

You should consult the documentation for [Graphics::Primitive::TextBox](http://search.cpan.org/perldoc?Graphics::Primitive::TextBox) for
things like padding and text rotation.  If you are adding it to the top and
want some padding between it and the plot, you can:

  $cc->title->padding->bottom(5);

## title_position

The position the title will be added.  Should be one of north, south, east,
west or center as required by [Layout::Manager::Compass](http://search.cpan.org/perldoc?Layout::Manager::Compass).

Note that if no angle is set for the title then it will be changed to
-1.5707 if the title position is east or west.

## width

Set/Get the width.  Defaults to 500.

# METHODS

## context_count

Get a count of contexts.

## context_names

Get a list of context names.

## delete_context ($name)

Remove the context with the specified name.

## get_context ($name)

Get the context with the specified name

## set_context ($name, $context)

Set a context of the specified name.

## add_to_datasets

Add the specified dataset (or arrayref of datasets) to the chart.

## dataset_count

Get a count of datasets.

## get_dataset ($index)

Get the dataset at the specified index.

## rendered_data

Returns the data for this chart as a scalar.  Suitable for 'streaming' to a
client.

## add_to_over_decorations

Add an over decoration to the list.

## get_over_decoration ($index)

Get the over decoration at the specified index.

## over_decoration_count

Get a count of over decorations.

## add_to_contexts

Add the specified context to the chart.

## add_subgraph

Add a subgraph to this chart.

## draw

Draw this chart.

## get_datasets_for_context

Returns an arrayref containing all datasets for the given context.  Used by
renderers to get a list of datasets to chart.

## add_data ($name, $data)

Convenience method for adding data to the chart.  Can be called one of three
ways.

- __scalar__

Passing a name and a scalar will "add" the scalar data to that series' data.

  $cc->add_data('Sales', 1234);
  $cc->add_data('Sales', 1235);

This will result in a Series names 'Sales' with two values.

- __arrayref__

Passing a name and an arrayref works much the same as the scalar method
discussed above, but appends the supplied arrayref to the existing one.  It
may be mixed with the scalar method.

  $cc->add_data('Sales', \@some_sales);
  $cc->add_data('Sales', \@some_more_sales);
  # This works still!
  $cc->add_data('Sales', 1234);

- __hashref__

This allows you to pass both keys and add in all at once, but it's an all-or-nothing
thing.  Subsequent calls with the same name will overwrite previous calls.

  $cc->add_data('Sales', { 2009 => 1234, 2010 => 1235 });
  # Overwrites last call!
  $cc->add_data('Sales', { 2011 => 1234, 2012 => 1235 });

## set_renderer ($renderer_object, [ $context ]);

Sets the renderer on the specified context.  If no context is provided then
'default' is assumed.

## write

This method is passed through to the underlying driver.  It is only necessary
that you call this if you manually called `draw` beforehand.  You likely
want to use `write_output`.

## write_output ($path)

Write the chart output to the specified location. Output is written in the
format provided to the constructor (which defaults to Png).  Internally
calls `draw` for you.  If you use this method, do not call `draw` first!

  $c->write_output('/path/to/the.png');

## inside_width

Get the width available in this container after taking away space for
insets and borders.

## inside_height

Get the height available in this container after taking away space for
insets and borders.

# ISSUES WITH CENTOS

I've had numerous reports of problems with Chart::Clicker when using CentOS.
This problem has usually be solved by updating the version of cairo.  I've
had reports that upgrading to at least cairo-1.8.8-3 makes thinks work properly.

I hesitate to provide any other data with this because it may get out of date
fast.  If you have trouble feel free to drop me an email and I'll tell you
what I know.

# CONTRIBUTORS

Many thanks to the individuals who have contributed various bits:

Ash Berlin

Brian Cassidy

Guillermo Roditi

Torsten Schoenfeld

Yuval Kogman

# SOURCE

Chart::Clicker is on github:

  http://github.com/gphat/chart-clicker/tree/master

# AUTHOR

Cory G Watson <gphat@cpan.org>

# COPYRIGHT AND LICENSE

This software is copyright (c) 2011 by Cold Hard Code, LLC.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.