Add a legend to the texture triangle

Usage

add_legend(
  x = 1,
  y = 0.7,
  box = FALSE,
  legend = c("Your fields", "Same county", "Same crop", "Other fields"),
  color = c("#a60f2dCC", "#3E3D3D99", "#3E3D3D99", "#ccc29c80"),
  pch = c(15, 17, 18, 19),
  size = c(2.4, 2.16, 2.16, 1.36),
  vertical_spacing = 1.5,
  ...
)

Arguments

x, y: X and Y coordinates used to position the legend. Location may also be specified by setting x to a single keyword from the list "bottomright", "bottom", "bottomleft", "left", "topleft", "top", "topright", "right", and "center".
box: Boolean. TRUE to draw a box around the legend. Defaults to FALSE for no box.
legend: Character vector to appear in legend.
color: Character vector of the color of the points.
pch: Numeric vector of plotting symbols. See graphics::points() for options and details.
size: Numeric expansion factor for points.
vertical_spacing: Numeric spacing factor for vertical line distances between each legend item.
...: Other arguments passed to graphics::legend().

Value

A list with list components for the legend's box and legend's text(s).

Examples

texture <- washi_data |>
  dplyr::select(
    sand = sand_percent,
    silt = silt_percent,
    clay = clay_percent
  )

make_texture_triangle(body_font = "sans")

# Add gray points
add_texture_points(
  tail(texture, 5),
  color = "#3E3D3D90",
  pch = 19
)

# Add red points
add_texture_points(
  head(texture, 5),
  color = "#a60f2dCC",
  pch = 15
)

# Add legend
add_legend(
  legend = c("Red squares", "Gray circles"),
  color = c("#a60f2dCC", "#3E3D3D90"),
  pch = c(15, 19),
  vertical_spacing = 2
)


# Note the text appears squished in this example since the width, height,
# and resolution have been optimized to print the figure 6 in wide in the
# report.