Mike Bostock

This also means that the fix for white in 1.2.5 was wrong. Both white and black should be treated as having undefined chroma, not zero. The problem is that when...

Unfortunately, the bisection method doesn’t work well for yellows. You get a discontinuity where it switches from a displayable color to a non-displayable color, and then suddenly drops the chroma....

Here’s my plot of the maximum displayable chroma by x=H & y=L (sorry for the lack of labels).  https://observablehq.com/d/4313e22e44483a1b

If I’m understanding correctly, then, it’s a misnomer for d3-color to treat LCh and HCL as aliases of the same color space. CIELCh is cylindrical CIELAB, whereas HCL is cylindrical...

This looks like a worthwhile refactoring and I’m in favor of exporting d3.xyz. 👍

Per @danburzo’s comment https://github.com/d3/d3-color/issues/51#issuecomment-720063360, what do you think about the choice of illuminant (D65 vs. D50)? One possibility is that the XYZ class has a field which stores the illuminant...

We should treat null/undefined/NaN as -Infinity, i.e., a value that is lower than any possible threshold and never included in any contour.

I suspect that this is related to numerical instability and I think it’s unlikely that we would implement a fully robust algorithm. Maybe we can at least guarantee consistency with...

The tricky thing is that for geographic coordinates (as in [GeoTIFF Contours II](https://bl.ocks.org/mbostock/83c0be21dba7602ee14982b020b12f51)) we want to retain the intersecting points along the antimeridian, which may not be possible if we...

I don’t think #47 is sufficiently helpful here: the points along straight lines occur not only when a contour polygon covers the entire frame, but whenever any contour polygon abuts...