from Matthias Pitzl; OK sthen@
Comment:
RGB color model for Perl
Description:
Graphics::Color::RGB represents a Color in the sRGB color space.
Individual color channels are expressed as decimal values from 0
to 1, 0 being a lack of that color (or opaque in the case of alpha)
and 1 being full color (or transparent in the case of alpha). If
no options are provided then new instance of RGB are opaque white,
(that is equivalent to red => 1, green => 1, blue => 1, alpha =>
1).