Cousin Ricky <ric### [at] yahoocom> wrote:
> On 2021-04-01 10:23 PM (-4), Kenneth wrote:
>
> > Long ago, either [Ive] or Clipka had given a different kind of example
> > of this, but used an rgb value of something like
> >            rgb <104,230,75>/255
> > and then warned about naively converting that to srgb with a simple
> >           srgb <104,230,75>/255
>
> ...This is exactly the sort of thing the srgb keyword was intended
> for.  Dividing by 255 is a special case because colors are often
> specified as byte values.  Hue distortion is not an issue here because
> we are not actually changing the luminance of the color; we are merely
> changing its representation.
>
> > So even though the *result* of the three divisions above is < 1.0 for each
> > vector component, the division operation itself still causes problems with
> > the new srgb hue? (With the correct solution again being to pre-#declare
> > it as
> >       srgb <.7,.8,.9>
> > and *then* to divide that by 255?)
>
> No, in this case dividing by 255 is unnecessary...

Aside from me being wrong about my first supposition above, I made a glaring
typo error in the 2nd part, that I just noticed. It must have caused some raised
eyebrows. What I meant to say was,

"(With the correct solution again being to pre-#declare it as
  ---->     srgb <104,230,75>   <----
and *then* to divide that by 255 [within the object or light]?)"

Sorry for the confusion. I don't yet know what the correct answer IS-- I'm still
working it out-- but dividing <.7,.8,.9>/255 made no sense, of course.

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