Weight Bars

An editable bar chart, such as a pitch-class histogram: twelve bars labelled C to B over a row coloured like piano keys, with the scale's notes highlighted and the tonic accented. Each bar is a vertical Base UI slider, so it is a native range input named by its label with arrows, Page Up/Down, Home and End. The pointer paints across bars: press to set the bar under it, drag sideways to set every bar crossed along a straight line, so a fast stroke leaves no gaps. Values draw clamped to the bar but an edit only rewrites the bars it touched, and a stroke commits once for one undo step. The pointer reading, the stroke and the colouring sit in a pure core beside it.