mapping letters to darkness for ASCII map

library(showtext)
font_add_google("Special Elite", "elite")
showtext_auto()

library(magick)
library(tidyverse)

# first part is common punctuation
chars = c(strsplit(intToUtf8(c(33:47, 58:64, 91:96)), "")[[1]], 
          0:9, letters, LETTERS)
fills = numeric(length(chars))

for(i in 1:length(chars)) {
  filename = tempfile(paste0("character_", i), fileext = ".png")
  
  ggplot() +
    geom_text(aes(x=a, y=b, label = chars[i]),
              family = "elite",
              data.frame(a = 1:10, b = 1:10) |>
                complete(a, b)) +
    theme_void()
  
  ggsave(filename, width = 0.5, height = 0.7, dpi = 300)
  
  r <- image_read(filename)
  r
  t <- image_trim(r)
  t
  image_data(t) %>%
    apply(2:3, paste, collapse = "") %>%
    as.vector %>% table() %>% as.data.frame %>%
    mutate(share = Freq / sum(Freq)) %>% 
    filter(. != "00000000") %>%
    summarize(share = sum(share)) %>%
    pull(share) -> fills[i]
  
  message(i)
}

data.frame(chars, fills) %>%
  arrange(fills) %>%
  mutate(chars = factor(chars %>% fct_inorder)) %>%
  ggplot(aes(chars, fills, label = chars)) +
  geom_text(family = "elite") +
  theme_void()