This is a followup to this question, modified for dynamic x-axis range. The idea is to have line segments at the bottom of the chart based on a boolean value, in this example when the price goes over 400.

Is there a way to have the rule mark (or any other mark) so that it joins on consecutive values? I could increase the stroke width however when I dynamically filter the date range it would break. Alternatively some formula to calculate the stroke width based on extents, but that seems overkill.

This is the example (based on the code below)

I’d like it to look something like this, i.e. the marks are joined no matter how much the x-axis is zoomed in or out:

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "description": "Google's stock price over time.",
  "data": {"url": "data/stocks.csv"},
  "transform": [
    {"filter": "datum.symbol==='GOOG'"},
    {"filter": {"timeUnit": "year", "field": "date", "lte": "2007"}},
    {"filter": {"timeUnit": "year", "field": "date", "gte": "2005"}},
    ],
  "encoding": {"x": {"field": "date", "type": "temporal"}},
  "layer": [
    {
      "mark": "area",
      "encoding": {"y": {"field": "price", "type": "quantitative"}}
    },
    {
      "transform": [
        {"calculate": "datum.price > 400 ? 1 : 0", "as": "high_price"}
      ],
      "mark": {"type": "rule", "strokeWidth": 4},
      "encoding": {
        "y": {"value": 201}, "y2":{"value":195},
        "opacity": {"field": "high_price", "type": "quantitative", "scale":{"rangeMin":0}, "legend":null},
        "color": {"value": "red"}
      }
    }
  ]
}