LineMark lacked a series: value, so Swift Charts merged every station's points into one polyline — only the first station's line was recognisable. Adding series: per station splits the chart into N coloured lines (legend colours now match).
LineMark lacked a series: value, so Swift Charts merged every station's points into one polyline — only the first station's line was recognisable. Adding series: per station splits the chart into N coloured lines (legend colours now match).