Behdad Esfahbod

> In fact, I think if the first group is only created in `PaintColorLayers`, and no extra two groups but only one is opened in `PaintComposite`, then I think there...

I created https://github.com/harfbuzz/harfbuzz/pull/4498 for HarfBuzz to follow your scheme.

Currently the paint algorithm in the spec says: ``` if format 1: // PaintColrLayers for each referenced child paint table, in bottom-up z-order: // for ordering, see Layering; Format 1:...

> Not yet: we can't build trial fonts without 32-bit VarStore in fonttools ([fonttools/fonttools#2279](https://github.com/fonttools/fonttools/issues/2279)). I hope to have enough by end of today to unblock you. > I immediately wonder...

> > Not yet: we can't build trial fonts without 32-bit VarStore in fonttools ([fonttools/fonttools#2279](https://github.com/fonttools/fonttools/issues/2279)). > > I hope to have enough by end of today to unblock you. This...

> Perhaps it's better to disallow it. I don't see how it is useful. Disallowing is typically too harsh. Call it undefined if same axis is set multiple times to...

I tried prototyping this. The FontTools side was simple: https://github.com/fonttools/fonttools/pull/3262 The HarfBuzz side however is proving to be impossible to implement given our abstractions. I'll try to elaborate more on...

> Vigorously agree we need better interpolation options. Do you think it would be fair to call this a duplicate of #356? I'm not sure it is either.

This seems more like https://developer.mozilla.org/en-US/docs/Web/CSS/transition-timing-function but for the color-line.

This makes sense. At the same time, I'm a bit concerned about features that are missing in common graphics libraries. I know cairo never got the full filter facilities in...