Add OkLrab and OkLrCh

[facelessuser]

Resolves #505

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[facelessuser]

Only lint issues related to this change were addressed.

[facelessuser]

This will clearly need a rework now that the null changes are in.

[facelessuser]

Rebase completed and is ready for review.

[svgeesus]

good catch, yes

[svgeesus]

Approved, one question but not a blocker

[svgeesus]

Should this actually be zero and this is cumulative error?

[facelessuser]

Yeah, cumulative floating point error.

Oklab in Color.js currently yields that for white, so OkLrab will also yield that for white as OkLrab just applies a toe function to the lightness, and at white, there is no change.

> new Color('white').to('oklab').coords
[ 1.0000000000000002, -4.996003610813204e-16, 0 ]

Floating point errors can vary slightly depending on how the original matrix was generated, the exact steps and in what order. The invert matrix result can be slightly different (floating point error-wise) depending on exactly how the inversion is performed (did it use LU decomposition, some other way, what order were operations done in, etc).

This isn't too different for other Lab-like spaces, especially those that employ more complicated calculations:

> new Color('white').to('ictcp').coords
[ 0.5806888810416109, 1.1102230246251565e-16, 2.914335439641036e-16 ]

I think my library has slightly different floating point errors. It yields an exact 1 for lightness, but non-zero results for both a and b.

>>> Color('white').convert('oklab').coords()
[1.0, -4.996003610813204e-16, 1.1102230246251565e-16]

But the same things happen for various other Lab-ish spaces (Y is the lightness in XYB):

>>> Color('white').convert('hunter-lab').coords()
[100.0, 1.912989643463523e-14, -7.46260389005987e-15]
>>> Color('white').convert('xyb').coords()
[0.0, 0.8453085619621621, 2.220446049250313e-16]

[svgeesus]

Someone more familiar with ts should probably look at the lint errors

[facelessuser]

Someone more familiar with ts should probably look at the lint errors

As far as this review is concerned, none of the lint errors apply to the code changes made in this PR. I consider these all existing, separate issues. I imagine it would be useful for someone to open a separate review to address these once and for all, but I do not consider any the lint errors to be blocking this review as they are unrelated and were not introduced by these changes.

[jgerigmeyer]

I do not consider any the lint errors to be blocking this review as they are unrelated and were not introduced by these changes

Agreed. If main is merged into this branch, CI may pass even with the lint errors.

[facelessuser]

Rebased and fixed imports due to recent changes on main. The lint action now passes. I think this can be considered done.