Using brush for fine-grained zooming about d3-brush

[Fil]

Is it something similar to https://blockbuilder.org/Fil/076415313a08e76ae60d468e2cb25909 ?

(related: d3/d3-zoom#222)

[ux-engineer]

@Fil yes it's very much similar implementation.

That example is triggering zoom in similar fashion by context.select(".brush").call(brush.move, x.range().map(t.invertX, t));

Trying out zooming there with dragging by mouse I can narrow down the zoom level to 4 days span, and then on it jumps somehow to a kind of zero span with label showing ':24' and no actual data drawn... Weird.

[Fil]

when you are brushing the selection s can be [387, 387] (it will be nulled when you release the mouse). At this point the code uses x.domain(s.map(x2.invert, x2)); and d3.zoomIdentity.scale(width / (s[1] - s[0])) and everything breaks on NaN.
A solution is to add a small value to the right-hand-side of the selection so that it's never 0 pixel wide

  var s = event.selection || x2.range();
+  s[1] += .5;

or more precisely

  var s = event.selection || x2.range();
+  if (s[1] === s[0]) s[1] += .5;