RGBAColor

[Brian Rice]

On Dec 18, 2004, at 2:42 PM, Lyndon Tremblay wrote:

> I am having difficulties sorting out (virtually) what should/shouldn't 
> be a
> full Color component. We have RGBColor, and HSVColor, where would 
> RGBAColor
> fit in? If just as an addition of alpha, then this would lead way to 
> such
> things as ARGBColor, but... ?
> OpenGL color4fv: ((ARGBColor a: 1.0 r: 1.0 g: 0.0 b: 0.0) asByteArray)
>
> OpenGL color: ((1.0 @ 1.0 @ 0.0 @ 0.0) as: RGBAColor)
>
> ... obviously I'm missing something very important, and require a
> publically-witnessable enlightening, gloriously archived on this ML.

Actually, it's sort of obvious in how you're using it in that code 
snippet. It's an implementation enhancement, and not conceptual at all. 
So it would fit in, in say, the root port.slate or something since 
multiple implementations use RGBA bytes to encode color and 
transparency.

At the abstract level that the UI provides, transparency is something 
you compose with a color or image or design, so it's just an object (a 
wrapper object) with an attribute of the transparency/opacity value.

Does that make sense?

--
Brian T. Rice
LOGOS Research and Development
http://tunes.org/~water/