std.experimental.color, request reviews

[Andrea Fontana via Digitalmars-d]

On Tuesday, 23 June 2015 at 14:58:35 UTC, Manu wrote:
> https://github.com/D-Programming-Language/phobos/pull/2845
>
> I'm getting quite happy with it.
> I think it's a good and fairly minimal but useful starting 
> point.
>
> It'd be great to get some reviews from here.

Some points about blend/lerp:

- Using operation on rgb components usually doesn't give the 
expected result. It should be done, for example, blending hue 
saturation and brightness, rather than Red, Blue, Green (or at 
least using toLinear?)

- What happens if srcFactor + destFactor != 1? Maybe we should 
normalize srcFactor and destFactor on 0..1 using something like:
normSrcFactor = srcFactor/(srcFactor+DestFactor);
normDestFactor = destFactor/(srcFactor+DestFactor);

- Does it work with RGB only?