Size of text/label keys (#5562)

* improve text label

* improve label labels

* add news bullet

NEWS.md

@@ -1,5 +1,7 @@
 # ggplot2 (development version)
 
+* `draw_key_label()` now better reflects the appearance of labels.
+
 * The `minor_breaks` function argument in scales can now take a function with
  two arguments: the scale's limits and the scale's major breaks (#3583).
 

R/legend-draw.R

@@ -236,26 +236,68 @@ draw_key_smooth <- function(data, params, size) {
 #' @export
 #' @rdname draw_key
 draw_key_text <- function(data, params, size) {
- if(is.null(data$label)) data$label <- "a"
-
- textGrob(data$label, 0.5, 0.5,
- rot = data$angle %||% 0,
+ data$label <- data$label %||% "a"
+ just <- rotate_just(data$angle, data$hjust, data$vjust)
+ grob <- titleGrob(
+ data$label,
+ x = unit(just$hjust, "npc"), y = unit(just$vjust, "npc"),
+ angle = data$angle,
+ hjust = data$hjust,
+ vjust = data$vjust,
  gp = gpar(
  col = alpha(data$colour %||% data$fill %||% "black", data$alpha),
- fontfamily = data$family %||% "",
- fontface = data$fontface %||% 1,
- fontsize = (data$size %||% 3.88) * .pt
- )
+ fontfamily = data$family %||% "",
+ fontface = data$fontface %||% 1,
+ fontsize = (data$size %||% 3.88) * .pt
+ ),
+ margin = margin(0.1, 0.1, 0.1, 0.1, unit = "lines"),
+ margin_x = TRUE, margin_y = TRUE
  )
+ attr(grob, "width") <- convertWidth(grobWidth(grob), "cm", valueOnly = TRUE)
+ attr(grob, "height") <- convertHeight(grobHeight(grob), "cm", valueOnly = TRUE)
+ grob
 }
 
 #' @export
 #' @rdname draw_key
 draw_key_label <- function(data, params, size) {
- grobTree(
- draw_key_rect(data, list()),
- draw_key_text(data, list())
+ data$label <- data$label %||% "a"
+ just <- rotate_just(data$angle, data$hjust, data$vjust)
+ padding <- rep(params$label.padding, length.out = 4)
+ descent <- font_descent(
+ family = data$family %||% "",
+ face = data$fontface %||% 1,
+ size = data$size %||% 3.88
+ )
+ grob <- labelGrob(
+ data$label,
+ x = unit(just$hjust, "npc"),
+ y = unit(just$vjust, "npc") + descent,
+ angle = data$angle,
+ just = c(data$hjust, data$vjust),
+ padding = padding,
+ r = params$label.r,
+ text.gp = gpar(
+ col = data$colour %||% "black",
+ fontfamily = data$family %||% "",
+ fontface = data$fontface %||% 1,
+ fontsize = (data$size %||% 3.88) * .pt
+ ),
+ rect.gp = gpar(
+ col = if (isTRUE(all.equal(params$label.size, 0))) NA else data$colour,
+ fill = alpha(data$fill %||% "white", data$alpha),
+ lwd = params$label.size * .pt
+ )
  )
+ angle <- deg2rad(data$angle %||% 0)
+ text <- grob$children[[2]]
+ width <- convertWidth(grobWidth(text), "cm", valueOnly = TRUE)
+ height <- convertHeight(grobHeight(text), "cm", valueOnly = TRUE)
+ x <- c(0, 0, width, width)
+ y <- c(0, height, height, 0)
+ attr(grob, "width") <- diff(range(x * cos(angle) - y * sin(angle)))
+ attr(grob, "height") <- diff(range(x * sin(angle) + y * cos(angle)))
+ grob
 }
 
 #' @export