Generate Point Overlay — generate_point

Calculates and returns an overlay of points for the current map.

generate_point_overlay(
  geometry,
  extent,
  heightmap = NULL,
  width = NA,
  height = NA,
  resolution_multiply = 1,
  pch = 20,
  color = "black",
  size = 1,
  offset = c(0, 0),
  data_column_width = NULL
)

Arguments

geometry: An `sf` object with POINT geometry.
extent: Either an object representing the spatial extent of the scene (either from the `raster`, `terra`, `sf`, or `sp` packages), a length-4 numeric vector specifying `c("xmin", "xmax","ymin","ymax")`, or the spatial object (from the previously aforementioned packages) which will be automatically converted to an extent object.
heightmap: Default `NULL`. The original height map. Pass this in to extract the dimensions of the resulting overlay automatically.
width: Default `NA`. Width of the resulting overlay. Default the same dimensions as height map.
height: Default `NA`. Width of the resulting overlay. Default the same dimensions as height map.
resolution_multiply: Default `1`. If passing in `heightmap` instead of width/height, amount to increase the resolution of the overlay, which should make lines/polygons/points finer. Should be combined with `add_overlay(rescale_original = TRUE)` to ensure those added details are captured in the final map.
pch: Default `20`, solid. Point symbol. `0` = square, `1` = circle, `2` = triangle point up, `3` = plus, `4` = cross, `5` = diamond, `6` = triangle point down, `7` = square cross, `8` = star, `9` = diamond plus, `10` = circle plus, `11` = triangles up and down, `12` = square plus, `13` = circle cross, `14` = square and triangle down, `15` = filled square, `16` = filled circle, `17` = filled triangle point-up, `18` = filled diamond, `19` = solid circle, `20` = bullet (smaller circle), `21` = filled circle blue, `22` = filled square blue, `23` = filled diamond blue, `24` = filled triangle point-up blue, `25` = filled triangle point down blue
color: Default `black`. Color of the points.
size: Default `1`. Point size.
offset: Default `c(0,0)`. Horizontal and vertical offset to apply to the polygon, in units of `geometry`.
data_column_width: Default `NULL`. The numeric column to map the width to. The maximum width will be the value specified in `linewidth`.

Value

Semi-transparent overlay with contours.

Examples

#Add the included `sf` object with roads to the montereybay dataset
if(run_documentation()) {
 monterey_city = sf::st_sfc(sf::st_point(c(-121.893611, 36.603056)))
 montereybay %>% 
   height_shade() %>%
   add_overlay(generate_point_overlay(monterey_city, color="red", size=12, 
                                   attr(montereybay,"extent"), heightmap = montereybay))  %>%
   add_shadow(ray_shade(montereybay,zscale=50),0.3) %>%
   plot_map()
}