Twisted polygon

The function below is based on a random process, and thus, results in a different output each time.

R Library:

library(ggplot2)

Function:

random_polygons <- function(n_edges = 4, n_polygons = 10, range_values = c(-10,10), 
                            colors = c('#FA2FBD', RColorBrewer::brewer.pal(5, name = 'Pastel1'), '#235347'), 
                            coord_polar = TRUE){
  
  # Generates random polygons
  # inspired by @venpopov from twitter
  #
  # Args:
  #   n_edges: number of edges of polygons 
  #   n_polygons: number of random generated polygons
  #   range_values: range of values for color coding the polygons
  #   colors: color palette based on ggplot2 color brewer colors, e.g. 'Pastel1'
  #   coord_polar: polar coordinates TRUE/FALSE
  # 
  # Returns:
  #   Plot of random polygons with emtpy background theme
  #   
  # v1.0 SG, 31.12.2019
  
  n_edges <-  as.numeric(n_edges)
  n_polygons <- as.numeric(n_polygons)
  ids <- rep(1:n_polygons, each = n_edges)
  values <-  rep(runif(n_polygons, -10, 10), each = n_edges)
  x_coord <- runif(n_edges*n_polygons, 1, 10)
  y_coord <- runif(n_edges*n_polygons, 1, 10)
  df_polygons <- data.frame(id = ids,
                            value = values,
                            x = x_coord,
                            y = y_coord)
  
  img <- ggplot2::ggplot(df_polygons, aes(x = x, y = y)) +
    geom_polygon(aes(fill = value, group = id)) +
    scale_fill_gradientn(colors = colors) + # different color palettes: see ?scale_fill_distiller
    theme_void() + # no background/grid/axes
    theme(legend.position = "none", 
          panel.background = element_rect(fill = "#f8f8f6", color = NA),
          plot.background = element_rect(fill = "#f8f8f6", color = NA),
          #panel.grid = element_blank(),   # Remove grid lines, which can look like a frame
          panel.border = element_blank()
          )
  
  if (coord_polar == TRUE){
    # structure + match.call to save call of the function
    structure(img + coord_polar(), CALL = match.call() ) 
  } else { 
    structure(img, CALL = match.call() ) 
  }
}

Apply function:

custom_colors <- c('#FA2FBD', RColorBrewer::brewer.pal(5, name = 'Pastel1'), '#235347')

random_polygons(n_edges = 5,
                n_polygons = 8,
                coord_polar = TRUE,
                colors = custom_colors)