NAME

Template::Plugin::Colour::HSV - Template plugin for HSV colours

SYNOPSIS

    [% USE col = Colour.HSV(50, 255, 128) %]

    [% col.hue %]                          # 50
    [% col.sat %] / [% col.saturation %]   # 255
    [% col.val %] / [% col.value %]        # 128

DESCRIPTION

This Template Toolkit plugin module creates an object that represents a colour in the HSV (hue, saturation, value) colour space.

You can create an HSV colour object by accessing the plugin directly:

    [% USE col = Colour.HSV(50, 255, 128) %]

Or via the Template::Plugin::Colour plugin, specifying the 'HSV' colour space in either upper or lower case.

    [% USE col = Colour( hsv = [50, 255, 128] ) %]
    [% USE col = Colour( HSV = [50, 255, 128] ) %]

The final option is to load the Colour plugin and then call the HSV method whenever you need a new colour.

    [% USE Colour;
       red   = Colour.HSV(0, 255, 204);
       green = Colour.HSV(120, 255, 204);
       blue  = Colour.HSV(240, 255, 204);
    %]

You can also access the plugin using the 'Color' name instead of 'Colour' (note the spelling difference).

    [% USE col = Color.HSV(50, 255, 128) %]
    [% USE col = Color( hsv = [50, 255, 128] ) %]
    [% USE Color;
       red   = Color.HSV(0, 255, 204);
       green = Color.HSV(120, 255, 204);
       blue  = Color.HSV(240, 255, 204);
    %]

METHODS

new(@args)

Create a new HSV colour. This method is invoked when you USE the plugin from within a template.

    [% USE Colour.HSV(50, 255, 128) %]

The colour is specified as three decimal values (or a reference to a list of three values) representing the hue (0-359 degrees), saturation (0-255) and value (0-255) components.

    [% USE Colour.HSV(50, 255, 128) %]
    [% USE Colour.HSV([50, 255, 128]) %]

Alternately you can use named parameters

    [% USE Colour.HSV( hue=50, saturation=255, value=128) %]
    [% USE Colour.HSV({ hue=50, saturation=255, value=128 }) %]

You can also create a Colour by calling the HSV method of the Colour plugin. It looks very similar to the above, but you only need the one USE directive.

    [% USE Colour;
       orange  = Colour.HSV(30, 255, 255);
       lighter = Colour.HSV(30, 127, 255);
       darker  = Colour.HSV(20, 255, 127);
    %]

copy(@args)

Copy an existing colour.

    [% orange  = Colour.HSV(30, 255, 255);
       lighter = orange.copy.saturation(127);
    %]

You can specify one or more of the 'hue', 'saturation' (or 'sat') or 'value' (or 'val') parameters to modify the new colour created.

    [% orange  = Colour.HSV('#ff7f00');
       lighter = orange.copy( saturation = 127 );
       darker  = orange.copy( value = 127 );
    %]

hue($h)

Get or set the hue of the colour. The value is decimal and clipped to the range 0-359.

    [% col.hue(300) %]
    [% col.hue %]           # 300

saturation($s)

Get or set the saturation of the colour. The value is decimal and clipped to the range 0..255

    [% col.saturation(255) %]
    [% col.saturation %]         # 255

Lazy people and bad typists will be pleased to know that sat() is provided as an alias for saturation().

value($v)

Get or set the value component of the colour. The value is decimal and clipped to the range 0..255

    [% col.value(255) %]
    [% col.value %]          # 255

Lazy people and bad typists will be pleased to know that val() is provided as an alias for value(). But to be honest, if you find it difficult typing those extra two characters for the greater good of increased clarity then you should be ashamed of yourself!

rgb($r,$g,$b)

Convert the HSV colour to one in the RGB (red, green, blue) colour space, by creating a new Template::Plugin::Colour::RGB object. If arguments are provided then these are passed to the RGB constructor for red, green, and blue parameters. Otherwise they are computed from the current HSV colour.

    [% USE hsv = Colour.HSV(210, 170, 48) %]

    [% rgb = hsv.rgb %]
    [% rgb.red       %]    # 16
    [% rgb.green     %]    # 32
    [% rgb.blue      %]    # 48

See Template::Plugin::Colour::RGB for further information.

AUTHOR

Andy Wardley <abw@cpan.org>, http://wardley.org

COPYRIGHT

Copyright (C) 2006-2012 Andy Wardley. All Rights Reserved.

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

SEE ALSO

Template::Plugin::Colour, Template::Plugin::Colour::RGB, Template::Plugin

cpanm Template::Plugin::Colour

perl -MCPAN -e shell
install Template::Plugin::Colour