Truchet tiles

library(tidyverse)
theme_set(theme_void() + theme(legend.position = "none"))

Triangle tiles

# set up the tiles data
tile1 <- tibble(x = c(0, 0, 1, 0, 1, 1, 0, 1),
                y = c(0, 1, 0, 0, 0, 1, 1, 0),
                g = factor(rep(1:2, each = 4)),
                tile = "tile1")
tile2 <- tibble(x = c(0, 0, 1, 0, 0, 1, 1, 0),
                y = c(0, 1, 1, 0, 0, 1, 0, 0),
                g = factor(rep(1:2, each = 4)),
                tile = "tile2")
# the next two tiles just reverse color
tile3 <- tile1 %>% 
  mutate(g = factor(rep(2:1, each = 4)),
         tile = "tile3")
tile4 <- tile2 %>% 
  mutate(g = factor(rep(2:1, each = 4)),
         tile = "tile4")

set.seed(20231030)
gtile <- ggplot(tile1, aes(x, y)) +
  geom_polygon(aes(fill = g, group = g), color = "black", linewidth = 2) + 
  coord_equal() + 
  # sample two colors randomly
  scale_fill_manual(values = sample(colors(), 2))

gtile

gtile %+% tile2

gtile %+% tile3

gtile %+% tile4

Now let’s make 10 x 10 times grid with these tiles!

mygrid <- expand_grid(row = 0:9, col = 0:9) %>% 
  mutate(tile_id = 1:n()) %>% 
  rowwise() %>% 
  mutate(tile = sample(c("tile1", "tile2", "tile3", "tile4"), 1)) %>% 
  full_join(bind_rows(tile1, tile2, tile3, tile4), by = "tile") %>% 
  mutate(x = col + x,
         y = row + y)

mygrid

# A tibble: 800 × 7
# Rowwise: 
     row   col tile_id tile      x     y g    
   <int> <int>   <int> <chr> <dbl> <dbl> <fct>
 1     0     0       1 tile3     0     0 2    
 2     0     0       1 tile3     0     1 2    
 3     0     0       1 tile3     1     0 2    
 4     0     0       1 tile3     0     0 2    
 5     0     0       1 tile3     1     0 1    
 6     0     0       1 tile3     1     1 1    
 7     0     0       1 tile3     0     1 1    
 8     0     0       1 tile3     1     0 1    
 9     0     1       2 tile4     1     0 2    
10     0     1       2 tile4     1     1 2    
# ℹ 790 more rows

ggplot(mygrid, aes(x, y)) +
  geom_polygon(aes(group = paste(tile_id, g), fill = g), color = "black", linewidth = 2) + 
  coord_equal() + 
  # sample two colors randomly
  scale_fill_manual(values = sample(colors(), 2))

Arc tiles

library(ggforce)
tile1 <- tibble(x0 = 1,
                y0 = 0,
                r0 = 0.5,
                start = 0,
                end = pi/2)

ggplot(tile1, aes(x0, y0)) +
  geom_arc_bar(aes(x0 = x0, y0 = y0, r0 = r0, r = 0.6, start = start, end = end)) 

arcs <- data.frame(
  start = seq(0, 2 * pi, length.out = 11)[-11],
  end = seq(0, 2 * pi, length.out = 11)[-1],
  r = rep(1:2, 5)
)

# Behold the arcs
ggplot(arcs) +
  geom_arc_bar(aes(x0 = 0, y0 = 0, r0 = r - 1, r = r, start = start,
                   end = end, fill = r)) + 
  coord_equal()