Add plotting functions. (#16)

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: wallis
 Title: Room squares in R
-Version: 0.0.0.9000
+Version: 0.0.0.9001
 Authors@R: 
     person("Matthew", "Henderson", , "[email protected]", role = c("aut", "cre"),
            comment = c(ORCID = "0000-0001-7949-8208"))
@@ -10,5 +10,8 @@ Encoding: UTF-8
 Roxygen: list(markdown = TRUE)
 RoxygenNote: 7.3.1
 Imports:
+  dplyr,
+  ggplot2,
   purrr,
+  tibble,
   tidyr

NAMESPACE

@@ -1,2 +1,3 @@
 # Generated by roxygen2: do not edit by hand
 
+export(plot_room_square)

R/grid-lines.R

@@ -0,0 +1,42 @@
+#' Horizontal grid lines
+#'
+#' @param n_rows Number of rows.
+#' @param n_cols Number of columns.
+#'
+#' @return A tibble with columns x, y, xend and yend.
+horiz_lines <- function(n_rows, n_cols) {
+  tibble::tibble(
+       x = rep(0, n_rows + 1)  + .5,
+       y = 0:n_rows + .5,
+    xend = rep(n_cols, n_rows + 1) + .5,
+    yend = 0:n_rows + .5
+  )
+}
+
+#' Vertical grid lines
+#'
+#' @param n_rows Number of rows.
+#' @param n_cols Number of columns.
+#'
+#' @return A tibble with columns x, y, xend and yend.
+vertical_lines <- function(n_rows, n_cols) {
+  tibble::tibble(
+       x = 0:n_cols + .5,
+       y = rep(0, n_cols + 1) + .5,
+    xend = 0:n_cols + .5,
+    yend = rep(n_rows, n_cols + 1) + .5
+  )
+}
+
+#' Horizontal and vertical grid lines
+#'
+#' @param n_rows Number of rows.
+#' @param n_cols Number of columns.
+#'
+#' @return A tibble with columns x, y, xend and yend.
+grid_lines <- function(n_rows, n_cols) {
+  dplyr::bind_rows(
+    horiz_lines(n_rows, n_cols),
+    vertical_lines(n_rows, n_cols)
+  )
+}

R/plot-room-square.R

@@ -0,0 +1,23 @@
+#' Plot a Room square
+#'
+#' @param R A Room square.
+#'
+#' @return A ggplot plot of Room square R
+#' @export
+plot_room_square <- function(R) {
+
+  n <- max(R$col) + 1
+
+  ggplot2::ggplot(data = R, ggplot2::aes(col, row)) +
+    ggplot2::geom_tile(data = R |> dplyr::filter(!is.na(first)), ggplot2::aes(fill = fill)) +
+    ggplot2::geom_segment(data = grid_lines(n - 1, n - 1), ggplot2::aes(x = x, y = y, xend = xend, yend = yend), linewidth = .1) +
+    ggplot2::geom_text(data = R |> dplyr::filter(!is.na(first)), ggplot2::aes(label = paste(first, second, sep = ","))) +
+    ggplot2::scale_y_reverse() +
+    ggplot2::coord_fixed() + 
+    ggplot2::theme_void() +
+    ggplot2::theme(
+      legend.position  = "none"
+    ) +
+    ggplot2::scale_fill_gradient(limits = c(0, choose(n, 2)), low = "white", high = "blue")
+
+}