Visualise SpatVector objects — ggspatvector • tidyterra

Wrappers of ggplot2::geom_sf() family used to visualise SpatVector objects (see terra::vect()).

Usage

geom_spatvector(
  mapping = aes(),
  data = NULL,
  na.rm = FALSE,
  show.legend = NA,
  ...
)

geom_spatvector_label(
  mapping = aes(),
  data = NULL,
  na.rm = FALSE,
  show.legend = NA,
  ...,
  nudge_x = 0,
  nudge_y = 0,
  label.size = 0.25,
  inherit.aes = TRUE
)

geom_spatvector_text(
  mapping = aes(),
  data = NULL,
  na.rm = FALSE,
  show.legend = NA,
  ...,
  nudge_x = 0,
  nudge_y = 0,
  check_overlap = FALSE,
  inherit.aes = TRUE
)

stat_spatvector(
  mapping = NULL,
  data = NULL,
  geom = "rect",
  position = "identity",
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE,
  ...
)

Arguments

mapping

Set of aesthetic mappings created by aes(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.

data

A SpatVector object, see terra::vect().

na.rm

If FALSE, the default, missing values are removed with a warning. If TRUE, missing values are silently removed.

show.legend

logical. Should this layer be included in the legends? NA, the default, includes if any aesthetics are mapped. FALSE never includes, and TRUE always includes.

You can also set this to one of "polygon", "line", and "point" to override the default legend.

...

Other arguments passed on to ggplot2::geom_sf() functions. These are often aesthetics, used to set an aesthetic to a fixed value, like colour = "red" or linewidth = 3.

nudge_x, nudge_y

Horizontal and vertical adjustment to nudge labels by. Useful for offsetting text from points, particularly on discrete scales. Cannot be jointly specified with position.

label.size

Size of label border, in mm.

inherit.aes

If FALSE, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. borders().

check_overlap

If TRUE, text that overlaps previous text in the same layer will not be plotted. check_overlap happens at draw time and in the order of the data. Therefore data should be arranged by the label column before calling geom_text(). Note that this argument is not supported by geom_label().

geom

The geometric object to use to display the data for this layer. When using a stat_*() function to construct a layer, the geom argument can be used to override the default coupling between stats and geoms. The geom argument accepts the following:

A Geom ggproto subclass, for example GeomPoint.
A string naming the geom. To give the geom as a string, strip the function name of the geom_ prefix. For example, to use geom_point(), give the geom as "point".
For more information and other ways to specify the geom, see the layer geom documentation.

position

A position adjustment to use on the data for this layer. This can be used in various ways, including to prevent overplotting and improving the display. The position argument accepts the following:

The result of calling a position function, such as position_jitter(). This method allows for passing extra arguments to the position.
A string naming the position adjustment. To give the position as a string, strip the function name of the position_ prefix. For example, to use position_jitter(), give the position as "jitter".
For more information and other ways to specify the position, see the layer position documentation.

Value

A ggplot2 layer

Details

These functions are wrappers of ggplot2::geom_sf() functions. Since a fortify.SpatVector() method is provided, ggplot2 treat a SpatVector in the same way that a sf object. A side effect is that you can use ggplot2::geom_sf() directly with SpatVector objects.

See ggplot2::geom_sf() for details on aesthetics, etc.

terra equivalent

terra::plot()

Examples

# \donttest{
# Create a SpatVector
extfile <- system.file("extdata/cyl.gpkg", package = "tidyterra")

cyl <- terra::vect(extfile)
class(cyl)
#> [1] "SpatVector"
#> attr(,"package")
#> [1] "terra"

library(ggplot2)

ggplot(cyl) +
  geom_spatvector()



# With params

ggplot(cyl) +
  geom_spatvector(aes(fill = name), color = NA) +
  scale_fill_viridis_d() +
  coord_sf(crs = 3857)


# Add labels
ggplot(cyl) +
  geom_spatvector(aes(fill = name), color = NA) +
  geom_spatvector_text(aes(label = iso2),
    fontface = "bold",
    color = "red"
  ) +
  scale_fill_viridis_d(alpha = 0.4) +
  coord_sf(crs = 3857)


# You can use now geom_sf with SpatVectors!



ggplot(cyl) +
  geom_sf() +
  labs(
    title = paste("cyl is", as.character(class(cyl))),
    subtitle = "With geom_sf()"
  )

# }

Visualise `SpatVector` objects