5 ms·

I have a fork of this that inverts the light model from additive to subtractive and suddenly its like ink in water https://observablehq.com/@tomlarkworthy/ink

I have a fork of this that inverts the light model from additive to subtractive and suddenly its like ink in water https://observablehq.com/@tomlarkworthy/ink https://observablehq.com/@tomlarkworthy/ink

doctorhandshake 2y ago
This was the first thing I did when I wrote a fluid sim as well - I’ve spent a ton of time and energy pursuing ways to get subtractive color effects (the richness and light-subjectivity of pigment) in digital artifacts and have mostly come up empty, but I take every chance I can get.
- snaily 2y ago
  Have you checked out mixbox[0]? The outputs do feel intuitively "right" as someone who has dabbled in watercolor, and the paper/videos cover the thinking and Kubelka-Munk theory well. [0] https://github.com/scrtwpns/mixbox https://github.com/scrtwpns/mixbox
  - tlarkworthy 2y ago
    oh wow, they have the fluid demo too!!! Thats so much better! https://scrtwpns.com/mixbox/fluids/ https://scrtwpns.com/mixbox/fluids/
  - doctorhandshake 2y ago
    Wild! Just saw that at the top of the front page and thought ‘dang is HN reading my mind today??’ Thanks for the link!
  - bj-rn 2y ago
    Spectral.js might also be interesting. It comes with a GLSL implementation of Kubelka-Munk and is MIT. https://github.com/rvanwijnen/spectral.js https://github.com/rvanwijnen/spectral.js
popalchemist 2y ago
How difficult would it be to prevent the ink from disappearing? Any tips would be appreciated, I'd love to integrate this into a drawing app.
- tlarkworthy 2y ago
  very easy, its a free parameter in the simulation see the "Ink dissipation" slider, you can set it to > 1 for some weird effects.
  - lgas 2y ago
    No such slider on mine. (https://i.imgur.com/m1tODYK.png https://i.imgur.com/m1tODYK.png)
    - tlarkworthy 2y ago
      you are looking at the wrong app https://observablehq.com/@tomlarkworthy/ink https://observablehq.com/@tomlarkworthy/ink
      - lgas 2y ago
        Ah, thanks.
SiggyF 2y ago
You could consider changing your ink to CMYK colors: `mutable ink = [255, 0, 255]`.

doctorhandshake 2y ago

This was the first thing I did when I wrote a fluid sim as well - I’ve spent a ton of time and energy pursuing ways to get subtractive color effects (the richness and light-subjectivity of pigment) in digital artifacts and have mostly come up empty, but I take every chance I can get.

snaily 2y ago
Have you checked out mixbox[0]? The outputs do feel intuitively "right" as someone who has dabbled in watercolor, and the paper/videos cover the thinking and Kubelka-Munk theory well. [0] https://github.com/scrtwpns/mixbox https://github.com/scrtwpns/mixbox
- tlarkworthy 2y ago
  oh wow, they have the fluid demo too!!! Thats so much better! https://scrtwpns.com/mixbox/fluids/ https://scrtwpns.com/mixbox/fluids/
- doctorhandshake 2y ago
  Wild! Just saw that at the top of the front page and thought ‘dang is HN reading my mind today??’ Thanks for the link!
- bj-rn 2y ago
  Spectral.js might also be interesting. It comes with a GLSL implementation of Kubelka-Munk and is MIT. https://github.com/rvanwijnen/spectral.js https://github.com/rvanwijnen/spectral.js

popalchemist 2y ago

How difficult would it be to prevent the ink from disappearing? Any tips would be appreciated, I'd love to integrate this into a drawing app.

tlarkworthy 2y ago
very easy, its a free parameter in the simulation see the "Ink dissipation" slider, you can set it to > 1 for some weird effects.
- lgas 2y ago
  No such slider on mine. (https://i.imgur.com/m1tODYK.png https://i.imgur.com/m1tODYK.png)
  - tlarkworthy 2y ago
    you are looking at the wrong app https://observablehq.com/@tomlarkworthy/ink https://observablehq.com/@tomlarkworthy/ink
    - lgas 2y ago
      Ah, thanks.

SiggyF 2y ago

You could consider changing your ink to CMYK colors: `mutable ink = [255, 0, 255]`.