Bar Chart
Bar charts are best for discrete comparisons. Use grouped bars to compare peers, a single series to rank categories, and stacked bars when both the total and its composition matter.
Grouped bars
Pass one y-accessor per series to VisGroupedBar. Keep the same key order in ChartRoot.config so the bars, tooltip rows, and legend use identical colors.
Single series
Use one accessor when each category has one value. A local series color and rounded corners can provide emphasis without adding a legend that repeats the axis labels.
Stacked bars
Use VisStackedBar for part-to-whole comparisons across several categories. Keep the legend visible because the segment names are not carried by the axis.
Start the value axis at zero unless the chart explicitly communicates a bounded deviation. Truncated bar axes exaggerate small differences in length.
Horizontal bars
Set orientation to Orientation.Horizontal when category labels need more room or when ranking is easier to scan from top to bottom. The data accessor stays on x and the value accessor stays on y; only their rendered axes change, so category ticks belong to the y-axis and numeric values belong to the x-axis.
Use Direction.South on the container to keep the first data item at the top. Because the standard crosshair follows the horizontal x-domain, attach ChartTooltip directly to GroupedBar.selectors.bar for horizontal bars.