truchet-tiles.qmd

---
title: "Truchet tiles"
execute: 
  message: false
  warning: false
---

```{r}
library(tidyverse)
theme_set(theme_void() + theme(legend.position = "none"))

# 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 4 x 4 times grid with these tiles!

```{r}
mygrid <- expand_grid(row = 0:3, col = 0:3) %>% 
  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
```

```{r}
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))
```