Add a gene label layer

Draws the gene annotation labels on a chord diagram. This layer is independent from geom_gene(): add it after geom_gene() to annotate the gene arrows with their texts.

Usage

geom_gene_label(
  mapping = NULL,
  data = NULL,
  gene_label_size = NULL,
  gene_label_orientation = "horizontal",
  gene_label_side = "outside",
  gene_label_overlap = "hide",
  gene_label_rotation = NULL,
  gene_label_radial_offset = 0.04,
  gene_label_circum_offset = NULL,
  gene_label_circum_limit = NULL,
  gene_label_wrap = NULL,
  show_legend = FALSE,
  ...
)

Arguments

mapping

Default NULL (uses pre-computed data)

data

Default NULL (retrieved automatically from the layout)

gene_label_size

Numeric. Label font size, default 2.5

gene_label_orientation

Character, default "horizontal". Text orientation relative to each sequence path: "radial", "tangent", or "horizontal".

gene_label_side

Character, default "outside". Place labels outside the chord, use the strand-based "auto" side, or force "inside" placement.

gene_label_overlap

Character, default "hide". Fixed-label collision policy: omit later conflicting labels ("hide"), apply the legacy gentle adjustment ("nudge"), or keep all requested positions ("allow"). Input row order therefore provides a simple way to prioritize labels in "hide" mode.

gene_label_rotation

Optional numeric/vector/list. Label rotation angle, default 0

gene_label_radial_offset

Optional numeric/vector/list. Radial offset of labels, default 0.04

gene_label_circum_offset

Optional numeric/vector/list. Circumferential offset of labels, default 0

gene_label_circum_limit

Optional logical/vector/list. Whether to limit circumferential offset, default TRUE

gene_label_wrap

Numeric or NULL, default NULL. When set, long gene annotations are wrapped at this many characters (e.g. 15), which makes the labels narrower and less prone to overlap.

show_legend

Whether to show the legend, default FALSE

...

Additional arguments passed to geom_text()

Value

A list of ggplot2 layers. To let the labels avoid each other and the genes (with leader lines), use geom_gene_label_repel() instead.

Details

This is the deterministic, fixed-position label layer. By default labels sit outside their sequence and labels that would collide are omitted in input-row order. Use gene_label_overlap = "nudge" to retain the legacy gentle adjustment, or "allow" to draw every label at its requested position. For automatic arrangement with leader lines, use geom_gene_label_repel() instead.

Examples

library(ggchord)
data(seq_data_example)
data(gene_data_example)
p <- ggchord(seq_data_example, gene_data = gene_data_example) +
  geom_seq() + geom_gene() + geom_gene_label()
p