include margins in the label translate

[Fil]

fixes #375

[Fil]

rebased

[mbostock]

A little explainer would be nice here… I’m finding it hard to follow what the logic was vs. what it should be. I feel like the current behavior was intentional (put the x-axis label as far right as possible to give it space); now I’m trying to decide what the new behavior should be, if the current one is not desirable.

[Fil]

The idea is to position the axis label relative to the "tip of the axis", instead of having it float to the far end. In the case of the OP, that gives:

before

after

[mbostock]

But what is the default label margin of 20?

[Fil]

That was to match (most of) the existing plots.

…

[mbostock]

Because normally there isn’t a second axis? It’s matching the 20 from here, I presume.

plot/src/plot.js

Lines 118 to 121 in 07cf90b

	marginTop = Math.max((xAxis === "top" ? 30 : 0) + facetMarginTop, yAxis || fyAxis ? 20 : 0.5 - offset),
	marginRight = Math.max((yAxis === "right" ? 40 : 0) + facetMarginRight, xAxis || fxAxis ? 20 : 0.5 + offset),
	marginBottom = Math.max((xAxis === "bottom" ? 30 : 0) + facetMarginBottom, yAxis || fyAxis ? 20 : 0.5 + offset),
	marginLeft = Math.max((yAxis === "left" ? 40 : 0) + facetMarginLeft, xAxis || fxAxis ? 20 : 0.5 - offset)

[Fil]

I see now that this branch works only in a few cases, and is far from working in general.

I've made an interactive here https://observablehq.com/d/79d3d39812dd3441 ; it seems to me that the behavior of the two first charts is desirable, i.e. that the label should be tied to the tip of the axis. But it would need to work in the four faceting possibilities (no faceting, x, y, x+y), for labelAnchor=left, and also for the vertical axis (which I haven't touched here either).

Maybe an alternative would be to have a configurable label.shift? (label.offset is for the orthogonal direction). I'm closing this for the time being.

[mbostock]

Nice notebook. That helps! 👍 It’s definitely tricky and I expect we do want some tweaks to the default behavior as well as likely new options.