ggpointless 0.3.0

New features

• New geom_unit_bar(), geom_unit_col(), and geom_unit_histogram() draw isotype / pictogram bar charts, where each bar is a stack of discrete unit cells (one cell = one observation by default). geom_unit_bar() counts observations like geom_bar(); geom_unit_col() uses pre-computed y like geom_col(); geom_unit_histogram() bins a continuous variable like geom_histogram(). Fractional y values produce a partial cell at the outer edge. All three work with coord_equal(), coord_polar(), coord_radial(), coord_flip(), and faceting. #15

• New label_cells(cell_size) helper pairs with cell_size to relabel the value axis in cell counts instead of raw units: pass it to scale_y_continuous(labels = ...) so a tick at y = 200 displays as 2 when cell_size = 100.

• New geom_gridline() draws (panel)grid lines as a layer on top of other geoms. Reads positions directly from the trained scales (no manual breaks needed), inherits line styling from theme(panel.grid.major.*) / panel.grid.minor.* for any property not explicitly overridden, and supports coord_polar() / coord_radial(). Use grids = "x" / "y" / c("x", "y") to pick axes; minor = TRUE to draw minor lines too. To remove the underlying theme grid, compose with + theme(panel.grid = element_blank()). #12

• New geom_path_fade(), geom_line_fade(), and geom_step_fade() draw paths, lines, and step functions with a linear alpha gradient along their length, so one or both ends fade to transparent. The fade_direction argument controls which end(s) fade ("end", "start", or c("start", "end")); alpha_fade_to sets the target alpha.

• New geom_segment_fade() draws individual line segments like geom_segment() but fades each segment along its own direction — the gradient follows the segment from (x, y) to (xend, yend), so it works at any angle. Accepts the same fade_direction and alpha_fade_to arguments as geom_path_fade(). #11

• New geom_curve_fade() draws Bézier curves like geom_curve() but with an alpha gradient along the curve direction. The fade follows from start to end point, so curves fade at any angle. Uses the same fade_direction and alpha_fade_to arguments as geom_segment_fade(), with Porter-Duff compositing for smooth gradients. Falls back to semi-transparent curves on unsupported devices. #11

• New geom_abline_fade(), geom_hline_fade(), and geom_vline_fade() draw reference lines (diagonal, horizontal, vertical) with an alpha gradient along the line direction. They mirror the ggplot2 annotation pattern: pass slope/intercept, yintercept, or xintercept directly for constant lines, or supply data and mapping for facet-varying lines. Under non-linear coordinate systems (coord_polar(), coord_radial()) the fade follows the curve that the coord transform produces — geom_hline_fade() fades around a circle, geom_vline_fade() fades along a ray, and geom_abline_fade() fades along the resulting arc.

• New geom_rect_fade() draws arbitrary rectangles with a linear alpha gradient that fades one edge to transparent. The fade_direction argument controls the gradient direction: "vertical" (default) fades from opaque at the top to transparent at the bottom; "horizontal" fades from opaque at the left to transparent at the right. Supports a radius argument for rounded corners too. #13

• New geom_col_fade(), geom_bar_fade(), and geom_histogram_fade() draw bar charts with a vertical alpha gradient that fades from opaque at the peak to transparent at the baseline. Additionally these geoms support a radius to draw bar charts with rounded corners The rendering tier is chosen at draw time: gradient fill on capable devices, flat semi-transparent fill on pdf()/postscript(). #14

• New geom_freqpoly_fade() draws a filled frequency polygon — the area under the geom_freqpoly() line — with the same fading gradient as geom_area_fade(). Paired with stat_bin(), so all binning parameters (bins, binwidth, center, boundary, …) are forwarded.

• New geom_density_fade() draws a kernel density estimate with a fading gradient, using geom_area_fade() paired with stat_density(). Accepts all smoothing parameters (bw, adjust, kernel, bounds, …).

• New geom_ridgeline_fade(), geom_ridgeline_density_fade(), geom_ridgeline_histogram_fade(), and geom_ridgeline_freqpoly_fade() draw ridgeline plots — overlapping ridge shapes at different vertical offsets — with a vertical alpha gradient that fades from opaque at each ridge’s peak to transparent at the baseline. The alpha_scope argument controls how alpha is scaled across ridges. geom_ridgeline_fade() takes explicit (x, y, height); the three other forms compute height from a stat (smooth density, stepped histogram, polyline frequency polygon) so users only supply (x, y). All four handle negative heights (dips below the baseline) with a bidirectional gradient. The scale argument defaults to NULL, which auto-scales the layer so the tallest ridge overlaps its neighbour by ~50% (the canonical “mountain range” ridgeline look). The auto-resolved value is reported via a cli::cli_inform() so you have a starting point if you want to override. #19

• New PositionRidgeline (callable via position = "ridgeline") is the position adjustment that converts a (y, height) mapping into the ribbon-style (ymin, ymax) form GeomRibbon expects, so each ridge sits on its own y-baseline. Used as the default position by geom_ridgeline_fade(), but also composes with vanilla [ggplot2::geom_ribbon()] for users who want the layout without the fade.

Breaking changes

• geom_point_glow(glow_size = X) now interprets X at face value in ggplot2 size units, matching the size aesthetic of [ggplot2::geom_point()]. Previously X was wrongfully multiplied by 3 before rendering, so existing user-supplied values render roughly three times smaller than in 0.2.0. The default (glow_size = NA) is unchanged and still renders at nine times the point’s size.

• Removed geom_lexis(point_size = ...), deprecated since 0.1.0 in favour of size. Code still passing point_size will now error with unused argument; rename the argument to size.

Bug fixes and improvements

• stat_chaikin() no longer renders nothing without a message when the smoothed data has missing values in different rows of (x, y) than in a numeric extra aesthetic (e.g. aes(fill = z) where z has its own NAs). Previously each numeric column was de-NA’d independently, the resulting per-column outputs had different lengths, the assignment errored, and ggplot2’s stat machinery silently swallowed the error — leaving an empty layer. The stat now pre-filters complete cases across all numeric columns once and warns about dropped rows in the standard ggplot2 way (suppress via na.rm = TRUE). #18

• stat_fourier() / stat_catenary() / stat_arch() no longer crash ggplot2’s limit expansion when paired with coord_transform(y = "log10") (and other restricted-domain transforms such as "log", "sqrt"). The stats now drop those rows with a single helpful warning that points users at scale_y_log10(), which transforms before the stat runs and avoids the issue entirely.

• stat_pointless() / geom_pointless(): when a single observation matches multiple location criteria — e.g. the last point is also the maximum — after_stat(location) now carries a composite label (e.g. "last, maximum") instead of silently dropping the secondary labels. Previously only the first matching label in iteration order was kept. Row order still follows the order given in location (canonical "first", "last", "minimum", "maximum" for "all").

• geom_area_fade(): now renders alpha gradient when + coord_flip() is applied. Previously the geom did not render any fill without a message or warning shown to users. #17

• geom_area_fade(): on devices without gradient support (base pdf(), postscript()) the informational message now fires for solid-fill plots too — users were previously silent about the lost vertical fade unless fill was mapped to a variable. Wording is tailored to what was actually lost (colour gradient vs. vertical fade). Devices that support gradients but not compositing still stay silent for solid-fill plots (tier 2 renders the vertical fade faithfully).

• geom_area_fade(): the global_max_abs scan that drives alpha_scope = "global" now handles Date and POSIXct value axes. Previously both failed is.numeric() and silently fell back to global_max = 1; plots built through the normal scale pipeline were unaffected (values are already numeric by draw time), but direct draw_panel() calls with raw Date / POSIXct ymax are now robust.

• geom_area_fade(): the legend key (.draw_key_area_fade()) now validates alpha_fade_to via the shared .check_alpha_fade_to() helper, matching the validation used by setup_params(). A guide that constructs a key outside the normal setup pipeline now aborts on out-of-range values instead of silently producing an invalid gradient.

• geom_area_fade(): fixed alpha overflow for stacked areas with alpha_scope = "global" (the default). The reference max was computed from the pre-stacking y values, so the top ribbon’s alpha exceeded 1 and was silently clamped to fully opaque, defeating the fade. The reference is now taken from post-position-adjustment data, so equal rendered |y| maps to equal opacity as documented. No effect on position = "identity" or alpha_scope = "group".

• geom_area_fade(): now accepts both integer and floating-point alpha_fade_to values (e.g. 0L, 0.5). Previously integer input was rejected.

• geom_area_fade(): fixed has_outline check to handle coord_polar() without crashing when outline colour is a vector.

• geom_area_fade(): fixed duplicate comp_stops that could arise when values were clipped to [0, 1] bounds (e.g. when val_hi is far outside the panel). Identical stops are now de-duplicated before gradient construction.

• geom_area_fade() under coord_flip() now rotates its alpha gradient to follow the rendered visual axis, instead of staying vertical and visually disappearing against horizontal bars. The gradient is now anchored to the rendered geometry via flipped_visual = xor(flipped_aes, CoordFlip), so coord_flip() and orientation = "y" produce equivalent output.

• New custom legend key glyphs for geom_fourier() (sine wave), geom_catenary() (hanging curve), and geom_arch() (arch curve) provide custom visual cues in the legend.

• All draw_key_*() functions now consistently use ggplot2::gg_par() instead of grid::gpar() for proper theme resolution in ggplot2 v4.0+.

ggpointless 0.2.0

New features

• New geom_fourier() and stat_fourier() fit a truncated Fourier series (via stats::fft()) to x/y data and render the reconstructed curve. Supports optional detrending ("lm" or "loess") and harmonic selection via n_harmonics (#7).

• New geom_arch() and stat_arch() draw inverted catenary curves (arches) between successive points, complementing the existing geom_catenary() (#4).

• New geom_area_fade() draws area charts where the fill colour fades from opaque to transparent using grid::linearGradient(). The fade target alpha is controlled via alpha_fade_to (#3).

• New geom_point_glow() draws points with a radial gradient glow behind each point using grid::radialGradient(). The glow alpha, colour, and size can be customised via glow_alpha, glow_colour, and glow_size (#6).

Breaking changes

• The bundled (but outdated) datasets co2_ml, covid_vac, and female_leaders have been removed from the package. These datasets can be obtained from their
  original sources: Mauna Loa CO₂, CDC vaccination data, and Wikipedia female leaders, respectively. The vignette("examples") that showcased these datasets has been removed alongside them.

Improvements

• The package now requires R >= 4.2.0 and ggplot2 >= 4.0.0. Several geoms take (mostly internal) advantage of new ggplot2 features such as make_constructor(), and gg_par().

• Messages and errors across the package have been migrated to the cli and rlang packages, giving consistent, hyperlink-aware output.

• geom_catenary() gained a vectorized chain_length argument and deprecated chainLength instead (#4).

• stat_catenary() no longer wrongfully removes data points when the upper limit in ylim() is set to the maximum y-value of the dataset (#1).

ggpointless 0.1.0

• New geom_catenary() and stat_catenary() let you draw a hanging chain.
• geom_lexis() supports linewidth argument now, which was released in ggplot2 v3.4.0.
• geom_lexis() deprecates point_size argument in favour of size.

ggpointless 0.0.3

• New geom_chaikin() and stat_chaikin() apply Chaikin’s corner cutting algorithm to ragged paths.

ggpointless 0.0.2

• New geom_lexis() and stat_lexis() draw lexis graphs.
• New female_leaders dataset available.

ggpointless 0.0.1

• New geom_pointless() and stat_pointless() emphasise some observations.
• New data sets on covid_vac and co2_ml added.