Add geom_marquee, and element_marquee along with various bug fixes in…

… marquee_grob found during development of the ggplot2 features

NAMESPACE

@@ -7,25 +7,27 @@ S3method(format,marquee_rem)
 S3method(format,marquee_skip_inherit)
 S3method(format,marquee_style)
 S3method(format,marquee_style_set)
-S3method(heightDetails,textboxgrob)
-S3method(makeContent,marquee)
+S3method(heightDetails,marquee_grob)
+S3method(makeContent,marquee_grob)
 S3method(makeContent,marquee_precalculated)
 S3method(makeContent,svg_grob)
-S3method(makeContext,marquee)
-S3method(makeContext,marquee_precalculated)
+S3method(makeContext,marquee_grob)
+S3method(makeContext,marquee_precalculated_grob)
 S3method(print,marquee_box)
 S3method(print,marquee_em)
 S3method(print,marquee_relative)
 S3method(print,marquee_rem)
 S3method(print,marquee_skip_inherit)
 S3method(print,marquee_style)
-S3method(print,marquee_style_set)
 S3method(str,marquee_style)
-S3method(widthDetails,textboxgrob)
+S3method(widthDetails,marquee_grob)
 export(base_style)
 export(box)
 export(classic_style)
+export(element_grob.element_marquee)
+export(element_marquee)
 export(em)
+export(geom_marquee)
 export(marquee_bullets)
 export(marquee_grob)
 export(marquee_parse)

R/element_marquee.R

@@ -0,0 +1,123 @@
+#' ggplot2 theme element supporting marquee syntax
+#'
+#' This theme element is a drop-in replacement for `ggplot2::element_text()`. It
+#' works by integrating the various style settings of the element into the base
+#' style of the provided style set. If a margin is given, it is set on the body
+#' tag with [skip_inherit()]. The default width is `NA` meaning that it will
+#' span as long as the given text is, doing no line wrapping. You can set it to
+#' any unit to make it fit within a specific width. However, this may not work
+#' as expected with rotated text (you may get lucky). Note that you may see
+#' small shifts in the visuals when going from `element_text()` to
+#' `element_marquee()` as size reporting may differ between the two elements.
+#'
+#' @param family The font family of the base style
+#' @param colour The font colour of the base style
+#' @param size The font size of the base style
+#' @param lineheight The lineheight of the base style
+#' @param margin The margin for the body tag
+#' @param style A style set to base the rendering on
+#' @param width The maximum width of the text. See the description for some
+#' caveats for this
+#' @inheritParams ggplot2::element_text
+#'
+#' @export
+#'
+#' @examples
+#' if (is_installed("ggplot2")) {
+#'   library(ggplot2)
+#'   p <- ggplot(mtcars) +
+#'     geom_point(aes(mpg, disp)) +
+#'     labs(title = "A {.red *marquee*} title\n* Look at this bullet list\n\n* great, huh?") +
+#'     theme_gray(base_size = 6) +
+#'     theme(title = element_marquee())
+#'
+#'   plot(p)
+#'
+#'   ggplot(mtcars) +
+#'     geom_histogram(aes(x = mpg)) +
+#'     labs(title = "I put a plot in your title so you can plot while you title\n\n![](p)\n\nWhat more could you _possibly_ want?") +
+#'     theme(title = element_marquee())
+#' }
+#'
+element_marquee <- function(family = NULL, colour = NULL, size = NULL, hjust = NULL,
+                            vjust = NULL, angle = NULL, lineheight = NULL,
+                            color = NULL, margin = NULL, style = NULL, width = NULL,
+                            inherit.blank = FALSE, ...) {
+  if (!is.null(color))
+    colour <- color
+  n <- max(length(family), length(colour), length(size),
+           length(hjust), length(vjust), length(angle), length(lineheight))
+  if (n > 1) {
+    cli::cli_warn(c("Vectorized input to {.fn element_text} is not officially supported.",
+                    i = "Results may be unexpected or may change in future versions of ggplot2."))
+  }
+  structure(list(family = family, colour = colour, size = size, hjust = hjust,
+                 vjust = vjust, angle = angle, lineheight = lineheight,
+                 margin = margin, style = style, width = width,
+                 inherit.blank = inherit.blank),
+            class = c("element_marquee", "element_text", "element"))
+}
+#' @export
+element_grob.element_marquee <- function(element, label = "", x = NULL, y = NULL, family = NULL,
+                                         colour = NULL, size = NULL, hjust = NULL, vjust = NULL,
+                                         angle = NULL, lineheight = NULL, margin = NULL, margin_x = FALSE,
+                                         margin_y = FALSE, style = NULL, width = NULL, ...) {
+  if (is.null(label)) return(ggplot2::zeroGrob())
+  style <- style %||% element$style %||% classic_style()
+  style <- modify_style(style, "base",
+    family = family %||% element$family %||% style$base$family,
+    color = colour %||% element$colour %||% style$base$color,
+    size = size %||% element$size %||% style$base$size,
+    lineheight = lineheight %||% element$lineheight %||% style$base$lineheight
+  )
+  margin <- margin %||% element$margin
+  if (!is.null(margin)) {
+    pad <- skip_inherit(box(
+      if (margin_y) margin[1] else 0,
+      if (margin_x) margin[2] else 0,
+      if (margin_y) margin[3] else 0,
+      if (margin_x) margin[4] else 0
+    ))
+    style <- modify_style(style, "body", padding = pad)
+  }
+  just <- rotate_just(angle %||% element$angle, hjust %||% element$hjust, vjust %||% element$vjust)
+  n <- max(length(x), length(y), 1)
+  x <- x %||% rep(just$hjust, n)
+  y <- y %||% rep(just$vjust, n)
+  width <- width %||% element$width %||% NA
+  angle <- angle %||% element$angle %||% 0
+  marquee_grob(label, style, x = x, y = y, width = width,
+               hjust = hjust %||% element$hjust, vjust = vjust %||% element$vjust, angle = angle)
+}
+
+on_load({
+  on_package_load("ggplot2", registerS3method("element_grob", "element_marquee", element_grob.element_marquee, asNamespace("ggplot2")))
+})
+
+# Adaption of ggplot2:::rotate_just() to work with additional just keywords
+rotate_just <- function (angle, hjust, vjust) {
+  angle <- (angle %||% 0)%%360
+  if (is.character(hjust)) {
+    hjust <- switch(hjust, "left" = , "left-ink" = 0, "center" = , "center-ink" = 0.5, "right" = , "right-ink" = 1)
+  }
+  if (is.character(vjust)) {
+    vjust <- switch(vjust, "bottom" = , "bottom-ink" = ,"last-line" = 0, "center" = , "center-ink" = 0.5, "top" = , "top-ink" = , "first-line" = 1)
+  }
+  size <- vctrs::vec_size_common(angle, hjust, vjust)
+  angle <- vctrs::vec_recycle(angle, size)
+  hjust <- vctrs::vec_recycle(hjust, size)
+  vjust <- vctrs::vec_recycle(vjust, size)
+  case <- findInterval(angle, c(0, 90, 180, 270, 360))
+  hnew <- hjust
+  vnew <- vjust
+  is_case <- which(case == 2)
+  hnew[is_case] <- 1 - vjust[is_case]
+  vnew[is_case] <- hjust[is_case]
+  is_case <- which(case == 3)
+  hnew[is_case] <- 1 - hjust[is_case]
+  vnew[is_case] <- 1 - vjust[is_case]
+  is_case <- which(case == 4)
+  hnew[is_case] <- vjust[is_case]
+  vnew[is_case] <- 1 - hjust[is_case]
+  list(hjust = hnew, vjust = vnew)
+}

R/geom_marquee.R

@@ -0,0 +1,180 @@
+#' Draw text formatted with marquee
+#'
+#' The geom is an extension of `geom_text()` and `geom_label()` that allows you
+#' to draw richly formatted text in marquee-markdown format in your plot. For
+#' plain text it is a near-drop-in replacement for the above geoms except some
+#' sizing might be very slightly different. However, using this geom you are
+#' able to access the much more powerful font settings available in marquee, so
+#' even then it might make sense to opt for this geom.
+#'
+#' @inheritParams ggplot2::geom_text
+#'
+#' @details
+#' Styling of the text is based on a style set with the exception that the
+#' standard aesthetics such as family, size, colour, fill, etc. are recognized
+#' and applied to the base tag style. The default style set ([classic_style])
+#' can be changed using the style aesthetic which can take a vector of style
+#' sets so that each text can rely on it's own style if needed. As with
+#' [element_marquee()], the `fill` aesthetic is treated differently and not
+#' applied to the base tag, but to the body tag as a [skip_inherit()] style so
+#' as to not propagate the fill.
+#'
+#' Contrary to the standard text and label geoms, `geom_marquee()` takes a
+#' `width` aesthetic that can be used to turn on soft wrapping of text. The
+#' default value (`NA`) lets the text run as long as it want's (honoring hard
+#' breaks), but setting this to something else will instruct marquee to use at
+#' most that amount of space. You can use grid units to set it to an absolute
+#' amount.
+#'
+#' @export
+#'
+#' @examples
+#' # Standard use
+#' p <- ggplot(mtcars, aes(wt, mpg))
+#' p + geom_marquee(aes(label = rownames(mtcars)))
+#'
+#' # Make use of more powerful font features (note, result may depend on fonts
+#' # installed on the system)
+#' p + geom_marquee(
+#'   aes(label = rownames(mtcars)),
+#'   style = classic_style(weight = "thin", width = "condensed")
+#' )
+#'
+#' # Turn on line wrapping
+#' p + geom_marquee(aes(label = rownames(mtcars)), width = unit(2, "cm"))
+#'
+#' # Style like label
+#' label_style <- modify_style(
+#'   classic_style(),
+#'   "body",
+#'   padding = skip_inherit(box(4)),
+#'   border = "black",
+#'   border_size = skip_inherit(box(1)),
+#'   border_radius = 3
+#' )
+#' p + geom_marquee(aes(label = rownames(mtcars), fill = gear), style = label_style)
+#'
+#' # Use markdown to style the text
+#' red_bold_names <- sub("(\\w+)", "{.red **\\1**}", rownames(mtcars))
+#' p + geom_marquee(aes(label = red_bold_names))
+#'
+geom_marquee <- function(mapping = NULL, data = NULL, stat = "identity",
+                         position = "identity", ..., size.unit = "mm",
+                         na.rm = FALSE, show.legend = NA, inherit.aes = TRUE) {
+  check_installed("ggplot2")
+
+  ggplot2::layer(
+    data = data, mapping = mapping, stat = stat, geom = GeomMarquee$geom,
+    position = position, show.legend = show.legend, inherit.aes = inherit.aes,
+    params = list2(size.unit = size.unit, na.rm = na.rm, ...)
+  )
+}
+
+GeomMarquee <- new_environment(list(geom = NULL))
+
+make_marquee_geom <- function() {
+  GeomMarquee$geom <- ggplot2::ggproto(
+    "GeomMarquee", ggplot2::Geom,
+
+    required_aes = c("x", "y", "label"),
+
+    default_aes = ggplot2::aes(
+      colour = "black", fill = NA, size = 3.88, angle = 0,
+      hjust = 0.5, vjust = 0.5, alpha = NA, family = "", lineheight = 1.2,
+      style = classic_style(), width = NA
+    ),
+
+    draw_panel = function(data, panel_params, coord, na.rm = FALSE, size.unit = "mm") {
+      lab <- data$label
+
+      styles <- data$style
+      if (!is_style_set(styles)) {
+        stop_input_type(styles, "a marquee_style_set object", arg = "style")
+      }
+      check_character(data$family, arg = "family")
+      size <- data$size * resolve_text_unit(size.unit) * 72.72 / 72
+      check_numeric(size, arg = "size")
+      check_numeric(data$lineheight)
+      colour <- ggplot2::alpha(data$colour, data$alpha)
+      check_character(colour, arg = "colour")
+      if (!is.character(data$fill) &&
+          !(is.logical(data$fill) && all(is.na(data$fill))) &&
+          !all(vapply(data$fill, function(x) is.character(x) || inherits(x, "GridPattern"), logical(1)))) {
+        stop_input_type(data$fill, "a character vector or a list of strings and patters", arg = "fill")
+      }
+      for (i in seq_along(styles)) {
+        styles[[i]]$base$family <- data$family[[i]]
+        styles[[i]]$base$size <- size[[i]]
+        styles[[i]]$base$lineheight <- data$lineheight[[i]]
+        styles[[i]]$base$color <- colour[[i]]
+        if (!"body" %in% names(styles[[i]])) {
+          styles[[i]]$body <- style()
+        }
+        styles[[i]]$body$background <- skip_inherit(data$fill[[i]])
+      }
+
+      data <- coord$transform(data, panel_params)
+
+      data$vjust <- compute_just(data$vjust, data$y, data$x, data$angle)
+      data$hjust <- compute_just(data$hjust, data$x, data$y, data$angle)
+
+      marquee_grob(
+        text = lab, style = styles,
+        x = data$x, y = data$y, width = data$width,
+        hjust = data$hjust, vjust = data$vjust,
+        angle = data$angle, name = "geom_marquee"
+      )
+    },
+
+    draw_key = ggplot2::draw_key_label
+  )
+}
+
+on_load(on_package_load("ggplot2", {
+ make_marquee_geom()
+}))
+
+combine_styles <- function(style, family, size, lineheight, color, background) {browser()
+  style <- modify_style(style, "base", family = family, size = size, color = color, lineheight = lineheight)
+  modify_style(style, "body", background = skip_inherit(background))
+}
+
+resolve_text_unit <- function(unit) {
+  unit <- arg_match0(unit, c("mm", "pt", "cm", "in", "pc", "Pt"))
+  switch(
+    unit,
+    "mm" = 2.845276,
+    "cm" = 28.45276,
+    "in" = 72.27,
+    "pc" = 12,
+    "Pt" = 72 / 72.27,
+    1
+  )
+}
+
+compute_just <- function (just, a = 0.5, b = a, angle = 0) {
+  if (!is.character(just)) {
+    return(just)
+  }
+  if (any(grepl("outward|inward", just))) {
+    angle <- angle%%360
+    angle <- ifelse(angle > 180, angle - 360, angle)
+    angle <- ifelse(angle < -180, angle + 360, angle)
+    rotated_forward <- grepl("outward|inward", just) & (angle > 45 & angle < 135)
+    rotated_backwards <- grepl("outward|inward", just) & (angle < -45 & angle > -135)
+    ab <- ifelse(rotated_forward | rotated_backwards, b, a)
+    just_swap <- rotated_backwards | abs(angle) > 135
+    inward <- (just == "inward" & !just_swap | just == "outward" & just_swap)
+    just[inward] <- c("left", "center", "right")[just_dir(ab[inward])]
+    outward <- (just == "outward" & !just_swap) | (just == "inward" & just_swap)
+    just[outward] <- c("right", "center", "left")[just_dir(ab[outward])]
+  }
+  just
+}
+
+just_dir <- function (x, tol = 0.001) {
+  out <- rep(2L, length(x))
+  out[x < 0.5 - tol] <- 1L
+  out[x > 0.5 + tol] <- 3L
+  out
+}