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    <p>Yep. See, for example #applySimpleGamma:to: in Cuis. Or
      ImageProcessing.pck.st</p>
    <p>BitBlt works essentially only on gamma space. But you need more
      than 8 bits per band to do image processing with reasonable
      quality. Usually Floating Point is best.</p>
    <div class="moz-cite-prefix">On 2025-12-09 5:21 PM, Nicolas Cellier
      via Cuis-dev wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CAKnRiT4AbUFUNiGrSXm3W-62Hoeoh3NVTtfh7_aoKsuTMby+ZQ@mail.gmail.com">
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      <div dir="ltr">
        <div>A connexe subject, here is one article explaining the gamma
          correction and sRGB color space</div>
        <div><a
href="https://blog.johnnovak.net/2016/09/21/what-every-coder-should-know-about-gamma/"
            moz-do-not-send="true" class="moz-txt-link-freetext">https://blog.johnnovak.net/2016/09/21/what-every-coder-should-know-about-gamma/</a><br>
        </div>
        <div>Normally most image processing should be performed in
          linear RGB color space, and I don't think that our BitBlt
          primitives really follow this rule...<br>
        </div>
        <div>Nicolas</div>
      </div>
      <br>
      <div class="gmail_quote gmail_quote_container">
        <div dir="ltr" class="gmail_attr">Le mar. 9 déc. 2025 à 19:46,
          Juan Vuletich via Cuis-dev <<a
            href="mailto:cuis-dev@lists.cuis.st" moz-do-not-send="true"
            class="moz-txt-link-freetext">cuis-dev@lists.cuis.st</a>>
          a écrit :<br>
        </div>
        <blockquote class="gmail_quote"
style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
          <div>
            <p><br>
            </p>
            <div>On 2025-12-09 3:07 PM, Luciano Notarfrancesco via
              Cuis-dev wrote:<br>
            </div>
            <blockquote type="cite">
              <div dir="auto">On Wed, Dec 10, 2025 at 00:21 Juan
                Vuletich <<a href="mailto:juan@cuis.st"
                  target="_blank" moz-do-not-send="true"
                  class="moz-txt-link-freetext">juan@cuis.st</a>>
                wrote:</div>
              <div dir="auto">
                <div class="gmail_quote">
                  <blockquote class="gmail_quote"
style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"
                    dir="auto"> <br>
                    Why didn't you use 0.0 and 1.0 as min and max
                    values?</blockquote>
                  <div dir="auto"><br>
                  </div>
                  <div dir="auto">I just followed the specification. The
                    chroma parameter doesn’t really have an upper limit,
                    I’m not sure why it was made in this way. In
                    practice, it doesn’t seem to make a difference to go
                    over 0.5, and CSS uses 0.4 as 100%.</div>
                </div>
              </div>
            </blockquote>
            <p>I wasn't clear. Apologies. I mean, in #okl:c:h: I read</p>
            <p>    min := -0.00001.<br>
                  max := 1.00001.</p>
            <p>I think I'd prefer 0.0 and 1.0, unless there's some
              reason for that I don't see.</p>
            <blockquote type="cite">
              <div dir="auto">
                <div class="gmail_quote">
                  <div dir="auto"><br>
                  </div>
                  <blockquote class="gmail_quote"
style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"
                    dir="auto">Would you provide the conversion from
                    sRGB (i.e. our Color instances) to <br>
                    OkLCH? That is really needed too. I'd also want an
                    instance creation <br>
                    method that answers nil if parameters lie outside
                    our sRGB space of <br>
                    Color instances (i.e. if the OkLCH values can not be
                    accurately <br>
                    represented by an instance of Color). Does
                    #okOrNilL:c:h: sound <br>
                    reasonable? Any better option? With these two, I
                    could do something like <br>
                    #experimentsTowardsANewColorPalette but using this
                    better color space.<br>
                  </blockquote>
                  <div dir="auto"><br>
                  </div>
                  <div dir="auto">Yeah, my idea was to try to do some
                    sort of parallel protocol for different color
                    spaces, something like aColor okLChDo: [:L :C :h|
                    …], HSLDo:, etc. Later we could rethink messages
                    like #hue (that currently returns the HSL hue, and
                    its different to the OkLCH hue), and I’m not sure if
                    we should eliminate those methods or make a unifying
                    choice of a specific color space and coordinates. </div>
                </div>
              </div>
            </blockquote>
            At least #okLCHhue, #okLCHluminance and #okLCHchroma are
            needed as a first step, it would be great if you could cook
            those. We can later decide if we want to keep HSL or not. We
            may decide to remove it.
            <blockquote type="cite">
              <div dir="auto">
                <div class="gmail_quote">
                  <div dir="auto">The message okOrNilL:c:h: might be ok,
                    aother option could be okl:c:h:ifFail: with a block
                    as argument, not sure. </div>
                </div>
              </div>
            </blockquote>
            <p>Yep. That's good too.</p>
            <blockquote type="cite">
              <div dir="auto">
                <div class="gmail_quote">
                  <div dir="auto">And perhaps later we could start
                    cleaning up all those messages like
                    veryVeryMuchDarker, quiteDarker, etc, or come up
                    with something better (should again look at what
                    designers do for these things, I think).</div>
                  <div dir="auto"><br>
                  </div>
                  <div dir="auto"><br>
                  </div>
                  <blockquote class="gmail_quote"
style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"
                    dir="auto">Finally, it would be wonderful to migrate
                    all our theme related stuff to <br>
                    this. This is so much better! Also, all our 'groups
                    of shades' and <br>
                    'transformations' methods look so primitive... We
                    really need to update <br>
                    all that stuff.<br>
                  </blockquote>
                  <div dir="auto"><br>
                  </div>
                  <div dir="auto">Yes, absolutely, I think it would be
                    great. I’ll try to help with anything necessary,
                    perhaps do it in small steps so that we don’t break
                    everyones themes. Hopefully more people will be
                    interested in helping with all this… it’s a fun
                    project and there are many small parts to it.</div>
                  <div dir="auto"><br>
                  </div>
                  <div dir="auto">Cheers,</div>
                  <div dir="auto">Luciano</div>
                </div>
              </div>
            </blockquote>
            <p>Thanks,</p>
            <pre cols="72">-- 
Juan Vuletich
<a href="http://www.cuis.st" target="_blank" moz-do-not-send="true">www.cuis.st</a>
<a href="http://github.com/jvuletich" target="_blank"
            moz-do-not-send="true">github.com/jvuletich</a>
<a href="http://researchgate.net/profile/Juan-Vuletich" target="_blank"
            moz-do-not-send="true">researchgate.net/profile/Juan-Vuletich</a>
<a href="http://independent.academia.edu/JuanVuletich" target="_blank"
            moz-do-not-send="true">independent.academia.edu/JuanVuletich</a>
<a href="http://patents.justia.com/inventor/juan-manuel-vuletich"
            target="_blank" moz-do-not-send="true">patents.justia.com/inventor/juan-manuel-vuletich</a></pre>
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            moz-do-not-send="true" class="moz-txt-link-freetext">Cuis-dev@lists.cuis.st</a><br>
          <a href="https://lists.cuis.st/mailman/listinfo/cuis-dev"
            rel="noreferrer" target="_blank" moz-do-not-send="true"
            class="moz-txt-link-freetext">https://lists.cuis.st/mailman/listinfo/cuis-dev</a><br>
        </blockquote>
      </div>
      <br>
      <fieldset class="moz-mime-attachment-header"></fieldset>
    </blockquote>
    <pre class="moz-signature" cols="72">-- 
Juan Vuletich
<a class="moz-txt-link-abbreviated" href="http://www.cuis.st">www.cuis.st</a>
github.com/jvuletich
researchgate.net/profile/Juan-Vuletich
independent.academia.edu/JuanVuletich
patents.justia.com/inventor/juan-manuel-vuletich</pre>
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