Text and fonts

fontface(fontname)

Select a font to use. (Toy API)

fontsize(n)

Set the font size to n points. The default size is 10 points. (Toy API)

setfont(family, fontsize)

Select a font and specify the size in points.

Example:

setfont("Helvetica", 24)
settext("Hello in Helvetica 24 using the Pro API", Point(0, 10))

text(str)
text(str, pos)
text(str, pos, angle=pi/2)
text(str, x, y)
text(str, pos, halign=:left)
text(str, valign=:baseline)
text(str, valign=:baseline, halign=:left)
text(str, pos, valign=:baseline, halign=:left)

Draw the text in the string str at x/y or pt, placing the start of the string at the point. If you omit the point, it's placed at the current 0/0. In Luxor, placing text doesn't affect the current point.

angle specifies the rotation of the text relative to the current x-axis.

Horizontal alignment halign can be :left, :center, (also :centre) or :right. Vertical alignment valign can be :baseline, :top, :middle, or :bottom.

The default alignment is :left, :baseline.

This uses Cairo's Toy text API.

settext(text, pos;
    halign = "left",
    valign = "bottom",
    angle  = 0, # degrees!
    markup = false)

settext(text;
    kwargs)

Draw the text at pos (if omitted defaults to 0/0). If no font is specified, on macOS the default font is Times Roman.

To align the text, use halign, one of "left", "center", or "right", and valign, one of "top", "center", or "bottom".

angle is the rotation - in counterclockwise degrees, rather than Luxor's default clockwise (+x-axis to +y-axis) radians.

If markup is true, then the string can contain some HTML-style markup. Supported tags include:

<b>, <i>, <s>, <sub>, <sup>, <small>, <big>, <u>, <tt>, and <span>

The <span> tag can contains things like this:

<span font='26' background='green' foreground='red'>unreadable text</span>

textpath(t)

Convert the text in string t to a new path, for subsequent filling/stroking etc...

textextents(str)

Return an array of six Float64s containing the measurements of the string str when set using the current font settings (Toy API):

1 x_bearing

2 y_bearing

3 width

4 height

5 x_advance

6 y_advance

The x and y bearings are the displacement from the reference point to the upper-left corner of the bounding box. It is often zero or a small positive value for x displacement, but can be negative x for characters like "j"; it's almost always a negative value for y displacement.

The width and height then describe the size of the bounding box. The advance takes you to the suggested reference point for the next letter. Note that bounding boxes for subsequent blocks of text can overlap if the bearing is negative, or the advance is smaller than the width would suggest.

Example:

textextents("R")

returns

[1.18652; -9.68335; 8.04199; 9.68335; 9.74927; 0.0]

label(txt::String, alignment::Symbol=:N, pos::Point=O;
    offset=5,
    leader=false)

Add a text label at a point, positioned relative to that point, for example, :N signifies North and places the text directly above that point.

Use one of :N, :S, :E, :W, :NE, :SE, :SW, :NW to position the label relative to that point.

label("text")          # positions text at North (above), relative to the origin
label("text", :S)      # positions text at South (below), relative to the origin
label("text", :S, pt)  # positions text South of pt
label("text", :N, pt, offset=20)  # positions text North of pt, offset by 20

The default offset is 5 units.

If leader is true, draw a line as well.

TODO: Negative offsets don't give good results.

label(txt::String, rotation::Float64, pos::Point=O;
    offset=5,
    leader=false,
    leaderoffsets=[0.0, 1.0])

Add a text label at a point, positioned relative to that point, for example, 0.0 is East, pi is West.

label("text", pi)          # positions text to the left of the origin

Place a string of text on a curve. It can spiral in or out.

textcurve(the_text, start_angle, start_radius, x_pos = 0, y_pos = 0;
          # optional keyword arguments:
          spiral_ring_step = 0,    # step out or in by this amount
          letter_spacing = 0,      # tracking/space between chars, tighter is (-), looser is (+)
          spiral_in_out_shift = 0, # + values go outwards, - values spiral inwards
          clockwise = true
          )

start_angle is relative to +ve x-axis, arc/circle is centered on (x_pos,y_pos) with radius start_radius.

textcurvecentered(the_text, the_angle, the_radius, center::Point;
      clockwise = true,
      letter_spacing = 0,
      baselineshift = 0

This version of the textcurve() function is designed for shorter text strings that need positioning around a circle. (A cheesy effect much beloved of hipster brands and retronauts.)

letter_spacing adjusts the tracking/space between chars, tighter is (-), looser is (+)). baselineshift moves the text up or down away from the baseline.

textcurvecentred (UK spelling) is a synonym

textwrap(s::T where T<:AbstractString, width::Real, pos::Point;
    rightgutter=5,
    leading=0)
textwrap(s::T where T<:AbstractString, width::Real, pos::Point, linefunc::Function;
    rightgutter=5,
    leading=0)

Draw the string in s by splitting it at whitespace characters into lines, so that each line is no longer than width units. The text starts at pos such that the first line of text is drawn entirely below a line drawn horizontally through that position. Each line is aligned on the left side, below pos.

See also textbox().

If you don't supply a value for leading, the font's built-in extents are used.

Text with no whitespace characters won't wrap. You can write a simple chunking function to split a string or array into chunks:

chunk(x, n) = [x[i:min(i+n-1,length(x))] for i in 1:n:length(x)]

textbox(lines::Array, pos::Point=O;
    leading = 12,
    linefunc::Function = (linenumber, linetext, startpos, height) -> (),
    alignment=:left)

Draw the strings in the array lines vertically downwards. leading controls the spacing between each line (default 12), and alignment determines the horizontal alignment (default :left).

Optionally, before each line, execute the function linefunc(linenumber, linetext, startpos, height).

See also textwrap(), which modifies the text so that the lines fit into a specified width.

splittext(s)

Split the text in string s into an array, but keep all the separators attached to the preceding word.