ggCheysson 1.2.0

Accepted on CRAN 2026-11-07: https://CRAN.R-project.org/package=ggCheysson. The main change: each element of each color-and-pattern palette is now a
'ggpattern' pattern of its own, a swatch, so a whole palette needs only aes(pattern = x) and
scale_cheysson(). New show_swatches() draws them all. Thanks to Trevor L. Davis (ggpattern / gridpattern)
for the pattern-registration API and advice.

Works with the current CRAN versions of ggpattern / gridpattern and with their upcoming versions; see
?cheysson_swatches for what pattern_spacing / pattern_density mean in each.

ggCheysson 1.2.0

New features

• Experimental: each element of each pattern palette is now a ggpattern pattern of its own, a
  swatch, named "<palette>-<element>" (e.g. "1886_28-1"), that draws its fill, hatch type, line
  colors and angle together. A whole color-and-pattern palette then needs only aes(pattern = x)
  and a pattern scale, e.g. scale_pattern_manual(values = paste0("1886_28-", 1:6)): no
  aes_cheysson(), and no pattern_spacing / pattern_density arguments. The swatches are
  registered when gridpattern loads, with gridpattern::register_pattern() where available.
  What setting pattern_spacing / pattern_density means depends on the ggpattern version; see
  ?cheysson_swatches.

• The swatches of a palette keep the relative line spacings measured on Cheysson's plates, so
  e.g. the hatching of sequential palette 1888_27 gets denser at each step. pattern_spacing
  sets the spacing of a palette's typical swatch, and the others keep their proportions. The
  literacy map in the Guerry maps vignette now uses scale_cheysson() instead of mapping
  pattern_spacing with scale_pattern_spacing_manual().

• New show_swatches() draws an atlas of the swatches: one row per palette and one column per
  element, grouped by palette type, so a swatch's name reads off its row and column. It is shown
  in the README.

• Experimental scale_cheysson() is now a single discrete scale for the pattern aesthetic that
  gives each level a swatch, so a palette needs only
  aes(pattern = x) + geom_col_pattern() + scale_cheysson("1886_28"). It used to return five
  scales, one per pattern aesthetic. Its aesthetics argument is ignored, with a warning; to use
  only some of a palette's properties, use the individual scale_*_cheysson() scales. na.value
  is now a pattern (default "none", which shows the geom's own fill) rather than a color.
  aes_cheysson(x) is deprecated and now the same as aes(pattern = x), so existing code using
  both keeps working. The "Combining Colors and Patterns" vignette is updated.

• The package's discrete scales no longer pass scale_name to ggplot2::discrete_scale() with
  ggplot2 3.5.0 or later, where it is deprecated.

Bug fixes

• The palette functions and scales (cheysson_pal(), cheysson_pattern(), scale_fill_cheysson(),
  scale_cheysson(), etc.) and cheysson_name() failed with "object 'cheysson_palettes' not found"
  (or 'cheysson_patterns', 'cheysson_labels') unless ggCheysson was attached with library(), e.g.
  when called as ggCheysson::scale_fill_cheysson() or from another package. They now find the
  palette data either way.

• cheysson_pattern_params() used %||%, which base R has only from 4.4.0, so it failed on the
  earlier R versions the package supports (R >= 3.5). The package now has its own.