Using Concaveman in R using V8

concaveman.R

# Using concaveman in R using V8
concaveman <- function(d){
  library(V8)
  ctx <- v8()
  ctx$source('https://www.mapbox.com/bites/00222/concaveman-bundle.js')
  jscode <- sprintf(
    "var points = %s;var polygon = concaveman(points);", 
    jsonlite::toJSON(d, dataframe = 'values')
  )
  ctx$eval(jscode)
  setNames(as.data.frame(ctx$get('polygon')), names(d))
}

# Example
d <- data.frame(
  x = runif(100),
  y = runif(100)
)

library(ggplot2)
ggplot(d, aes(x = x, y = y)) +
  geom_point() +
  geom_path(data = concaveman(d))