Segment mark — mark_segment • vellumplot

mark_segment() draws a straight line from (x, y) to (xend, yend) per row.

Usage

mark_segment(
  plot,
  ...,
  auto = FALSE,
  blend = NULL,
  effects = list(),
  sketch = NULL,
  data = NULL
)

Arguments

plot: A PlotSpec (from vplot()).
...: Encodings (tidy-eval): x, y, xend, yend (+ color, linewidth, linetype, alpha).
auto: For mark_point(), mark_line(), mark_step(), mark_segment(), and mark_edges(), when TRUE and the layer has very many rows, automatically render it as a datashaded density raster (see mark_datashade()) instead of individual vector marks: points bin into a density grid (vellum::datashade()), dense lines/steps rasterise as connected polylines (vellum::datashade_lines()), and segments/edges as independent segments (vellum::datashade_segments()). The datashaded line/segment output is dynspread-ed so thin marks stay visible (see the spread argument of mark_datashade()). The fallback is skipped under a warped coordinate system (coord_polar() / coord_trans()), which draws the vector marks instead.
blend: Optional blend mode for compositing this layer against what is already drawn beneath it (the panel and earlier layers), one of the CSS mix-blend-mode names, e.g. "multiply", "screen", "darken". The whole layer composites as one isolated group (not per element).
effects: A list of layer render effects applied to the mark at draw time — glow(), outline(), and shadow(). Available on stroked and point marks.
sketch: A sketch() spec giving this layer a hand-drawn look (wobbly outlines, hachure fills), NA/FALSE to force it crisp (overriding a plot-wide theme_sketch()), or NULL (default) to inherit. Geometry marks accept it; text, raster, hex and datashade marks do not.
data: Optional layer data frame; overrides the plot data for this layer.

Value

The modified PlotSpec.

Examples

d <- data.frame(x = 1, y = 1, xend = 5, yend = 4)
vplot(d) |> mark_segment(x = x, y = y, xend = xend, yend = yend)