Renders a legend from a data frame that combines icon grid rows (built with icon_grid), colour tile rows, and typed-symbol rows via rbind(). Layout parameters determine where each section is positioned. The scale parameter multiplies all size and spacing values so the data frame can be written in round numbers.

Usage

legend_canvas(
  df_legend,
  grid_section = "grid",
  grid_title = NULL,
  group_section = NULL,
  group_title = NULL,
  group_width = NULL,
  group_gap = 0.08,
  group_label_size = NA_real_,
  group_label_color = "white",
  group_swatch_height = 0.44,
  symbol_section = NULL,
  symbol_right_gap = 0.3,
  symbol_key_width = 0.2,
  symbol_label_gap = NULL,
  col_spacing,
  row_spacing,
  label_gap,
  marker_size,
  label_size,
  scale = 1,
  dpi = 300,
  xlim = NULL,
  ylim = NULL,
  x_margin = c(0.1, 1),
  y_margin = c(0.6, 1.1),
  clip = "off"
)

Arguments

df_legend

Data frame with columns section, type, label, color, icon, row, col. Optional columns: label_size, lineheight. type selects how a row renders and which columns it needs:

icon: An icon marker (via geom_icon_point) placed at row/col. Only meaningful inside grid_section; requires icon, row, col.
swatch: A filled rectangle - colour tiles, frontier bands. Requires color.
line: A horizontal line segment - e.g. an efficient-frontier sample. Requires color.
point: A bold "*" glyph (or a custom character via an optional pch column). Requires color.

swatch/line/point rows are rendered by key_legend - add a new type there, not here. icon rows go through marker_legend instead, a separate path.

grid_section

Value of section identifying icon grid rows (default "grid").

grid_title

Title drawn above the icon grid (NULL = none).

group_section

Value of section identifying colour tile rows. NULL skips the group section.

group_title

Title drawn above the colour tiles. Inherits group_section when NULL.

group_width

Width of the colour tile section.

group_gap

Gap between the tile right edge and x = 0.

group_label_size

Label size inside tiles; inherits label_size (after scaling) when NA.

group_label_color

Label colour inside tiles (default "white").

group_swatch_height

Tile height as fraction of row_spacing (default 0.44).

symbol_section

Value of section identifying typed-symbol rows. NULL skips the symbol section.

symbol_right_gap

Gap between icon grid right edge and symbol section (default 0.30).

symbol_key_width

Width of the key symbol area (default 0.20).

symbol_label_gap

Gap between key symbol and label; inherits label_gap (after scaling) when NULL.

col_spacing

Horizontal distance between icon grid columns.

row_spacing

Vertical distance between rows.

label_gap

Default gap between key symbol and label.

marker_size

Icon size for the grid.

label_size

Default label text size.

scale

Multiplier applied to col_spacing, row_spacing, label_gap, marker_size, label_size, and the label_size column in df_legend. Use to scale the whole legend without touching individual values (default 1).

dpi

Icon render resolution (default 300).

xlim

Length-2 numeric; x limits of the canvas. Auto-computed when NULL.

ylim

Length-2 numeric; y limits of the canvas. Auto-computed when NULL.

x_margin

Length-2 numeric: left/right padding added to auto x range (default c(0.10, 1.00)).

y_margin

Length-2 numeric: top/bottom padding as multiples of (scaled) row_spacing (default c(0.6, 1.1)).

clip

Passed to coord_cartesian (default "off").

Value

A ggplot ready to save or pass to legend_strip.

Build a composite legend from a plain data frame

Usage

Arguments

Value

See also