Skip to contents

Plot bathymetry and terrain rasters

Source: R/plotting.R
plot_bathy.Rd

Creates ggplot2 maps for bathymetry and derived terrain metrics using terra rasters and vectors. Hillshade can be drawn as a semitransparent visual relief layer, and bathymetric contours, sampling rectangles, transects, or other terra::SpatVector geometries can be overlaid.

Usage

plot_bathy(
  x,
  hillshade = TRUE,
  hillshade_alpha = 0.3,
  contours = TRUE,
  contour_interval = NULL,
  contour_color = "white",
  contour_linewidth = 0.25,
  vectors = NULL,
  vector_color = "white",
  vector_linewidth = 0.5,
  labels = NULL,
  label_field = NULL,
  title = NULL,
  subtitle = NULL,
  caption = NULL,
  legend_title = "Bathymetry",
  max_cells = getOption("blueterra.max_plot_cells", 10000)
)

plot_metric(
  x,
  metric = NULL,
  bathy = NULL,
  hillshade = TRUE,
  hillshade_alpha = 0.3,
  contours = FALSE,
  contour_interval = NULL,
  contour_color = "white",
  contour_linewidth = 0.25,
  vectors = NULL,
  vector_color = "white",
  vector_linewidth = 0.5,
  labels = NULL,
  label_field = NULL,
  title = NULL,
  subtitle = NULL,
  caption = NULL,
  legend_title = NULL,
  max_cells = getOption("blueterra.max_plot_cells", 10000)
)

plot_terrain_map(
  bathy,
  metric = NULL,
  vectors = NULL,
  contours = TRUE,
  contour_interval = 20,
  hillshade = TRUE,
  title = NULL,
  subtitle = NULL,
  caption = NULL,
  ...
)

plot_hillshade(x, max_cells = getOption("blueterra.max_plot_cells", 10000))

plot_sampling_rectangles(bathy, rectangles, label_field = "site_id", ...)

plot_transects(bathy, transects, color_by = NULL, show_legend = FALSE, ...)

plot_metric_stack(x, max_cells = getOption("blueterra.max_plot_cells", 10000))

Arguments

x

A raster-like object accepted by as_bathy().

hillshade

Logical. Draw hillshade as a visual relief layer.

hillshade_alpha

Maximum alpha for the hillshade shadow overlay.

contours

Logical. Draw contour lines from bathy or x.

contour_interval

Optional contour interval in raster units.

contour_color

Contour line color.

contour_linewidth

Contour line width.

vectors

Optional terra::SpatVector, sf object, or local vector path drawn over the raster.

vector_color

Vector outline color.

vector_linewidth

Vector outline width.

labels

Optional label source. Use TRUE to label vectors, or supply a vector object/path.

label_field

Optional field used for vector labels.

title, subtitle, caption

Plot text passed to ggplot2::labs().

legend_title

Optional raster legend title.

max_cells

Maximum raster cells used for plotting.

metric

Optional metric raster or a layer name/index in bathy.

bathy

Optional bathymetry raster used to derive hillshade and contours when x is a metric raster.

...

Additional plotting options passed from convenience wrappers to plot_bathy() or plot_metric().

rectangles

Sampling rectangles or polygon zones.

transects

Transect line geometry.

color_by

Optional transect attribute used to color lines, such as "transect_id".

show_legend

Logical. Show a legend when color_by is supplied.

Value

A ggplot object.

Details

Plotting functions require ggplot2, which is suggested rather than imported. Large rasters are regularly sampled before plotting to keep examples and interactive work responsive. Hillshade is used only as a visual relief layer; it is not a terrain predictor unless a user explicitly derives and analyzes it as one.

See also

derive_terrain(), plot_metric_stack()

Examples

if (requireNamespace("ggplot2", quietly = TRUE)) {
  bathy <- read_bathy(blueterra_example("bathy"))
  zones <- terra::vect(blueterra_example("zones"))
  plot_bathy(bathy, vectors = zones, labels = TRUE, label_field = "site_id")
}