Text boxes and decorations (2024)

library(unikn) # load unikn package

slide() # plot default slide

xbox() # plot default xbox

Colors

The background and border colors of slides can be changed by settingtheir col, border, and lwdarguments:

slide(col = pal_seeblau[[1]], border = Petrol, lwd = 5) # set colors of slide background and border

slide(col = pal_peach[[2]], border = NA) # colored slide without a border

Similarly, the background color of xboxes can be changed by thecol argument:

xbox(col = Pinky) # set background color of xbox

Dimensions

By default, both slide and xbox fill theentire plotting region (i.e., all margins are set to 0).

The width of a slide is set to 4/3of its height (of1). To changethis default, use the dimargument for specifying theslide’s x- and y-dimensions, respectively:

slide(dim = c(3, 1)) # a slide 3 times wider than high

Note that changes in slide dimensions are invisible when viewingimages interactively, as R automatically scales images to the size ofthe canvass. They mostly affect the relation between metrics when addingelements to anobject.

Similarly, an xbox has the default dimensions of a unit square (i.e.,dim = c(1, 1)). To change this default, use thedim argument for specifying the xbox’s x- andy-dimensions, respectively:

xbox(col = Petrol, dim = c(1, 2)) # an xbox 2 times higher than wide

The two strokes of theX (in the top right corner) are orthogonalwhen viewing the xbox at the aspect ratio indicated bydim (i.e., here: at a ratio of width x = 1 to height y =2). When viewing the box at any different aspect ratio, the X appears tobe distorted. Hence, viewing and printing plots at the desired aspectratio helps when creating an xbox.

Mark text

The mark() function allows highlighting text by plottingit with colored background boxes (to provide the functionality of“Markieren”):

By default, mark() assumes that we want to addhighlighted text to anexisting plot. The text labels to be added areprovided (as a character vector) by the labels argument,their coordinates as the correspondingx andyarguments. Various text decorations (i.e., text and background colors,text sizes, and font types) can be set by specifying additionalarguments (i.e., col, col_bg,cex, and font, respectively):

# Some pre-existing plot: n <- 20set.seed(1)par(mar = c(0, 0, 0, 0))plot(x = runif(n), y = runif(n), type = "p", pch = 16, cex = 20, col = grey(0, .2), axes = FALSE, xlab = "", ylab = "")# Add 1 marked label:mark(labels = "Some messy plot", x = .02, y = .9)# Add 2 more marked labels:mark(labels = c("Note something here.", "More highlighting here."),  x = c(.1, .6), y = c(.2, .4), col_bg = c(pal_seeblau[[2]], pal_peach[[3]]), cex = 1.2)

If no pre-existing plot is available, setting thenew_plot argument to either"blank"or"slide" will generate a new default plot (by calling theslide() function described above):

# A sentence to plot: s <- c("Markieren", "ist ein Bestandteil", "von Studieren.")# Create a new plot (of type "slide"):mark(labels = s, x = 0, y = .85, y_layout = .03, col_bg = Seeblau, cex = 1.5, new_plot = "slide")# Add text to the same plot:mark(labels = s, x = 0, y = .40, y_layout = .03, col_bg = pal_pinky[[2]], cex = 1.5,  new_plot = "none")

Rather than providing explicit xandycoordinates for all text elements inlabels,the calls above defined an initial coordinate and used a numericy_layout argument to fix the distance between consecutivetext labels (to a value of.03).

As an alternative to numeric coordinates and position values,x_layout and y_layout also accept some specialvalues (as character strings):

1. x_layout accepts:

   • x_layout = "center" for centering labels horizontally(on the first label or the middle),
     
   • x_layout = "left" left-justifies labels (on the firstlabel or the middle), and
     
   • x_layout = "right" right-justifies labels (on the firstlabel or the middle).

2. y_layout accepts:

   • y_layout = "even" for an even distribution of labelsacross the available y-space, and
     
   • y_layout = "flush" to omit space between adjacentlabels (as in y_layout = 0).

Thus, the position and orientation of the text labels can becontrolled by using the x_layout and y_layoutoptions:

See ?mark for details.

Underline text

The uline() function allows emphasizing text by plottingit with colored underlining (to provide the functionality of“Unterstreichen”):

As with mark() above, the uline() commanddistinguishes between creating a new plot (by settingnew_plot to either "blank" or“slide”) or adding to a pre-existing plot (by using thedefault new_plot = "none"):

lbl_uline <- c("This is neat, true, and terribly important")uline(labels = lbl_uline, new_plot = "blank", y = .6, cex = 1.1) # create a new plotuline(labels = "(which is why we underline it).", y = .45, cex = 1) # add to plot

The arguments for text elements (labels), text positions(x, y, y_layout), and textproperties and decorations (col, col_bg,cex, and font) work as they do formark(). For instance, shorter vectors are recycled to matchthe length of labels:

slogan <- c("Geradlinig", "Farbenfroh", "Beweglich", "Bunt", "Paradiesisch")uline(labels = slogan, x = c(0, .5), y = .9, y_layout = "even", col = c("black", Bordeaux), col_bg = c(Seeblau, Seegruen),  cex = 1.1, font = 2, new_plot = "blank")

The position and orientation of the text labels can be controlled byusing the x_layout and y_layout options:

Post text

The post() function allows adding text to arectangularxbox (to provide the functionality of“Merken”):

By default, post() assumes a pre-existingxbox to which the text elements of labels areto be added.
For square boxes, setting new_plot to "xbox"creates a newxbox with its default dimensions ofdim = c(1, 1).
By adjusting its color and text arguments, post() allowscreating simple badges or logos:

# Badge (to view as 250 x 250 pixel):post(labels = "ToDo", y = .35,  col = "white", col_bg = pal_signal[[1]], cex = 3, font = 2, new_plot = "xbox") # Badge (to view as 250 x 250 pixel):post(labels = "R", y = .35,  col = "white", col_bg = pal_seeblau[[5]], cex = 8, font = 2, new_plot = "xbox")

Another potential use of post() is for creating imagesproviding contact details:

address <- c("Dr. B. F. Skinner", " ", "Department of Psychology", "Office Z101", "Tel.: +49 7531 88-0815", "Fax: +49 7531 88-0810", "b.f.skin@uni-konstanz.de")post(labels = "Contact", y = .7, cex = 1.2, font = 2, col_bg = Petrol, new_plot = "xbox") # create new plot post(labels = address, y = .5, y_layout = .03, new_plot = "none") # add to plot

As above, the position and orientation of the text labels can becontrolled by using the x_layout and y_layoutoptions:

Headings

The heading() function makes it easy to createrecognizable headings:

By default, the function creates a new slide (i.e.,new_plot = "slide") and positions the text elementsoflabels on its left edge (i.e., x = 0,y = .8 and y_layout = "flush"). When headingsviolate the official recommendations, a message is provided:

heading(labels = c("Ewig", "währt am", "längsten..."),  y = 2/3, col_bg = usecol(pal_pinky))

Re-arranging words helps to avoid step-wise titles (see p.25 of theCDmanual):

# Beware of step-wise arrangements:heading(labels = c("Ich", "bin keine", "gute Headline."))#> Step-wise titles are discouraged: Consider re-arranging?

# Avoiding warning:heading(labels = c("Ich bin", "eine alternative", "Headline."))

When colors are left unspecified, heading() selectscolors that are appropriate for the number of elements inlabels (i.e., shades of Seeblau forcol_bg = "default"). However, default colors can beoverwritten by setting thecol andcol_bgarguments:

heading(labels = c("Ene,", "mene, miste,", "es rappelt", "in der Kiste."),  col = "white", col_bg = c(Pinky, Seegruen, Bordeaux, Karpfenblau))

URLs

One of the more obscure rules (on p.31 of the CD manual) concernsthe rendering of URLs, in which typical web patterns (like “http” or“www”) are to be omitted and replaced by a typographical dash (which islonger than a hyphen). The url_unikn utility functionallows formatting URLs the uni.kn way:

my_url <- url_unikn("https://www.uni-konstanz.de/") # input URL as copied from web browsermy_url # formatted URL#> [1] "‒ uni-konstanz.de"# Put URL at bottom of an xbox:post(labels = my_url, x = .05, y = .1, font = 4,  col_bg = pal_seeblau[[5]], new_plot = "xbox")