[thclark]

Summary

The default width of a bar becomes 0.55 of the pitch instead of 0.8, which gives a lighter and more elegant default chart. The change applies wherever the default is taken: Default for BarWidth and therefore Default for Bar, the Protocol Buffers decoding of an absent width, and the facade's bar and barh.

The bars helper's default gap between clusters becomes 0.45 instead of 0.2, so that a cluster occupies 0.55 of the pitch and a single series drawn with bars is stored exactly as one drawn with bar. Histograms are unaffected, because hist and hists place touching bars on the widths of their bins with an explicit gap of 0.

Tests

• The IR, facade, scene and web tests that pinned the old defaults now expect 0.55 of the pitch and a helper gap of 0.45. Tests that set a width or a gap explicitly are unchanged.
• A new facade test checks that a lone series of bars, upright and lying flat, is stored with the same positions, values, bases, width, offset, margin and style as bar stores the same data.

Documentation

The figure schema reference, the getting-started guide and the rustdoc of BarWidth, Bar, bar, bars, BarMut::width_pitch and BarsMut::gap state the new defaults.

Gallery

Two figures rely on the defaults and change: bar_chart, whose grouped clusters are narrower with wider spaces between them, and every panel of bar_variants. Both read well. No other figure changes.