Add scalebar to frames

This function adds a scalebar to the animation frames created with frames_spatial.

add_scalebar(
  frames,
  distance = NULL,
  height = 0.015,
  position = "bottomleft",
  x = NULL,
  y = NULL,
  colour = "black",
  label_margin = 1.2,
  units = "km",
  verbose = TRUE
)

Arguments

frames	list of ggplot2 objects, crated with frames_spatial.
distance	numeric, optional. Distance displayed by the scalebar (in either km or miles defined by argument units) By default, the displayed distance is calculated automatically.
height	numeric, height of the scalebar in a range from 0 to 1 as the proportion of the overall height of the frame map. Default is 0.015.
position	character, position of the scalebar on the map. Either "bottomleft", "upperleft", "upperright", "bottomright". Ignored, if x and y are set.
x	numeric, position of the bottom left corner of the scalebar on the x axis. If not set, position is used to calculate the position of the scalebar.
y	numeric, position of the bottom left corner of the scalebar on the y axis. If not set, position is used to calculate the position of the scalebar.
colour	character, colour of the distance labels. Default is "black".
label_margin	numeric, distance of the labels to the scalebar as a proportion of the height of the scalebar (e.g. if set to 2, the labels will be positioned with a distance to the scalebar of twice the scalebar height).
units	character, either "km" for kilometers or "miles" for miles.
verbose	logical, if TRUE, messages and progress information are displayed on the console (default).

Value

List of frames.

See also

frames_spatial frames_graph animate_frames

Examples

library(moveVis)
library(move)

data("move_data", "basemap_data")
m <- align_move(move_data, res = 4, unit = "mins")

# create spatial frames using a custom NDVI base layer
r_list <- basemap_data[[1]]
r_times <- basemap_data[[2]]

if (FALSE) {
frames <- frames_spatial(m, r_list = r_list, r_times = r_times, r_type = "gradient",
                         fade_raster = TRUE)

# add a scale bar to frames:
frames.a <- add_scalebar(frames)
frames.a[[100]]

# or in white at another position
frames.b <- add_scalebar(frames, colour = "white", position = "bottomright")
frames.b[[100]]

# or with another height
frames.c <- add_scalebar(frames, colour = "white", position = "bottomright", height = 0.025)
frames.c[[100]]
}