transparency

Hi Marco!

Here I'm sending the transparency part of my code, as we discussed.
I hope it'll be useful.

Cheers,
Daniel
I would still like to just specify the RGB components alone, without having to write an alpha of 1 every time. It should be sufficient to just add that feature to forceRGB. In case you are getting a vector of length 3, just return a vector of length 4, with the alpha component set to 1. This will also make your change backwards compatible with existing code.