Scale

<Chart scale={[0, max()]}>
  <Scale ticks={every(5, { ends: true })}>{Mark}</Scale>
  <Plot …>{Slat}</Plot>
</Chart>

A Scale is a Plot of ticks from the Chart’s scale. Its slat is drawn once per tick, and all its slats share one band that covers the chart. A Chart with a Scale in it draws no axis of its own. Because a Scale uses overlap, a slat drawing only a Tick can return that Tick directly. Use a wrapper when its slat draws a Tick and a separately positioned Label.

Prop	Default	What it does
ticks	about 5	a list of values, a rough count, or a function of [min, max] such as every(5)
other props		data for the slats, as in a Plot
class		the Scale’s element

What a tick’s slat gets

d.at	the tick’s value
d.next	the next tick’s value (the scale’s end after the last tick): fill the space between two ticks
d.first, d.last	true for the first and last ticks
d.toEnd	the distance from the tick to the scale’s end, in px, measured in the browser (Infinity until then, and on a server). CSS does the same job everywhere: see scales.

A tick keeps its slat while the scale changes, so a tick at 20 stays the same element as the scale grows. The ticks at the two ends of the scale are always the same two slats, so the end line never slides.