How to draw lines between any two highs or lows of the candlestick bars to make a slanted trend line that can extend to left or right or both directions?
Extending left or right by creating a custom series manually using y = mx + b formula seems plausible, but a direct straight-forward method would be more appropriate.
It's impossible right now. lightweight-charts doesn't support drawings at all (except workaround for drawing trend line with series with the only 2 points).
We aren't going to add drawing itself to the library, but we thought about extending the API to allow you draw on canvas directly. If you'd like to use drawings, I can suggest you take a look at charting_library.
to draw diagonal trend line use addLineSeries: https://jsfiddle.net/pv62e9da/5/
lineSeries = chart.addLineSeries({
lastValueVisible: false
});
var tldata = [];
tldata.push({
time: data[3].time,
value: data[3].close
});
tldata.push({
time: data[50].time,
value: data[50].close
});
lineSeries.setData(tldata);
