question_mark.R

library(string2path)
library(ggplot2)

d <- string2path("?", "/usr/share/fonts/truetype/roboto/unhinted/RobotoTTF/Roboto-BoldItalic.ttf")


f <- function(d, theta) {
  d <- dplyr::mutate(d, x = x + 0.02 * cos(theta * 3.2), y = y + 0.02 * sin(theta * 2.1))
  
  d2 <- dplyr::bind_rows(
    dplyr::mutate(d, glyph_id = 1, path_id = sprintf("%d-%d", glyph_id, path_id), rgb = "#ff0000", x = x + rnorm(1, sd = 0.008), y = y + rnorm(1, -0.001, sd = 0.007)),
    dplyr::mutate(d, glyph_id = 2, path_id = sprintf("%d-%d", glyph_id, path_id), rgb = "#00ff00", x = x + rnorm(1, sd = 0.008), y = y + rnorm(1,  0.000, sd = 0.007)),
    dplyr::mutate(d, glyph_id = 3, path_id = sprintf("%d-%d", glyph_id, path_id), rgb = "#0000ff", x = x + rnorm(1, sd = 0.008), y = y + rnorm(1, +0.001, sd = 0.007))
  )
  
  p <- ggplot() +
    geom_polygon(data = d2, aes(x, y, group = path_id, fill = rgb), alpha = 0.5) +
    geom_polygon(data = d,  aes(x, y, group = path_id), fill = "black") +
    theme_minimal() +
    coord_equal(xlim = c(-0.05, 0.45), ylim = c(-0.05, 0.55)) +
    theme(legend.position = "top") +
    scale_fill_identity()
  
  invisible(plot(p))
}

gifski::save_gif(
  for (i in 1:120) {
    f(d, 2 * pi * i / 120)
  },
  delay = 1/60
)