lofifonts provides access to raw data for the included bitmap and vector fonts.

Bitmap and vector fonts allow for bespoke rendering of pixels and strokes in situations where fine control over rendering is required. For example, individual pixels and strokes could be animated to create novel effects like exploding or coalescing text. With access to coordinates, variations in 3D also become possible.

This package will render text with a specified bitmap or vector font to:

• a data.frame of coordinates (for bitmap fonts)
• a data.frame of character strokes (for vector coordinates)
• a binary matrix indicating the rendered text
• a raster image of the rendered text

• Bitmap font functions
  • bitmap_text_coords() create a data.frame of pixel locations
  • bitmap_text_matrix() create a binary matrix with pixel locations set to 1
  • bitmap_text_raster() create a raster image of the text
• Vector font functions
  • vector_text_coords() create a data.frame of strokes
  • vector_text_matrix() create a binary matrix with pixel locations set to 1
  • vector_text_raster() create a raster image of the text

Bitmap fonts:

• Spleen v2.1.0 License: BSD 2-clause. See LICENSE-spleen.txt
• Tamzen v1.11.6 Free to distribute
• Unifont v16.0.0.1 License: SIL Open Font License (OFL) version 1.1. See LICENSE-unifont.txt
• Unscii v2.0 Font is in the public domain.

Vector fonts

• gridfont License: MIT. See LICENSE-gridfont.txt
• arcade is a vector font I created. License: SIL Open Font License (OFL) version 1.1. See LICENSE-arcade.txt

This package can be installed from CRAN

install.packages('lofifonts')

You can install the latest development version from GitHub with:

# install.package('remotes')
remotes::install_github('coolbutuseless/lofifonts')

Pre-built source/binary versions can also be installed from R-universe

install.packages('lofifonts', repos = c('https://coolbutuseless.r-universe.dev', 'https://cloud.r-project.org'))

get_lofi_names('bitmap')

#>  [1] "spleen-12x24"  "spleen-16x32"  "spleen-32x64"  "spleen-5x8"   
#>  [5] "spleen-6x12"   "spleen-8x16"   "tamzen10x20b"  "tamzen10x20r" 
#>  [9] "tamzen5x9b"    "tamzen5x9r"    "tamzen6x12b"   "tamzen6x12r"  
#> [13] "tamzen7x13b"   "tamzen7x13r"   "tamzen7x14b"   "tamzen7x14r"  
#> [17] "tamzen8x15b"   "tamzen8x15r"   "tamzen8x16b"   "tamzen8x16r"  
#> [21] "unifont"       "unscii-8"      "unscii-8-thin"

get_lofi_names('vector')

#> [1] "arcade"          "gridfont"        "gridfont_smooth" "asteroids"

Text may be rendered with a bitmap font to

1. A data.frame of pixel locations
2. A binary matrix of pixel locations
3. A simple raster object

library(lofifonts)
bitmap_text_coords("Hello", font = 'unifont') |>
  head()

#>      char_idx codepoint x  y line x0 y0
#> 2524        1        72 7 12    0  7 12
#> 2525        1        72 2 12    0  2 12
#> 2526        1        72 7 11    0  7 11
#> 2527        1        72 2 11    0  2 11
#> 2528        1        72 7 10    0  7 10
#> 2529        1        72 2 10    0  2 10

bitmap_text_raster("Hello", "unifont") |>
  plot()

# Render codepoints directly
bitmap_text_raster(intToUtf8(c(0x1f44d, 0x1f44e)), "unifont") |>
  plot()

This is an example of bespoke rendering of the pixel data for an example string.

Each pixel in the coords data.frame has an x and y coordinates, and to render this font, a small square will be drawn for each pixel.

A gap will be left between the rectangles to highlight the pixelated origin of the text.

library(grid)
coords <- bitmap_text_coords("Hello\n#RStats", "spleen-6x12")
head(coords)

#>     char_idx codepoint x  y line x0 y0
#> 516        1        72 5 23    0  5 11
#> 517        1        72 1 23    0  1 11
#> 518        1        72 5 22    0  5 10
#> 519        1        72 1 22    0  1 10
#> 520        1        72 5 21    0  5  9
#> 521        1        72 1 21    0  1  9

grid.newpage()
grid.rect(
  x = coords$x * 4, 
  y = coords$y * 4, 
  width  = 3, 
  height = 3, 
  default.units = 'mm',
  gp = gpar(fill = rainbow(nrow(coords)), col = NA)
)

Text may be rendered with a vector font to

1. A data.frame of stroke endpoints
2. A binary matrix of pixel locations
3. A simple raster object

library(lofifonts)
vector_text_coords("Hello") |> 
  head()

#>     char_idx codepoint stroke_idx         x        y line        x0       y0
#> 494        1       104          1 0.0000000 9.000000    0 0.0000000 9.000000
#> 495        1       104          1 0.0000000 3.000000    0 0.0000000 3.000000
#> 496        1       104          2 0.0000000 5.666667    0 0.0000000 5.666667
#> 497        1       104          2 0.1666667 6.333333    0 0.1666667 6.333333
#> 498        1       104          2 0.6666667 6.833333    0 0.6666667 6.833333
#> 499        1       104          2 1.1666667 7.000000    0 1.1666667 7.000000

vector_text_raster("Hello\n#RStats!", scale_coords = 5) |>
  plot()

This is an example of bespoke rendering of the strokes for an example string.

For each character (char_idx) there are 1-or-more strokes (stroke_idx). Each stroke has has 2 or more rows giving the path for this particular stroke.

When plotting with ggplot, draw paths for stroke-within-character.

library(ggplot2)

coords <- vector_text_coords("Hello")
head(coords)

#> # A tibble: 6 × 8
#>   char_idx codepoint stroke_idx     x     y  line    x0    y0
#>      <int>     <int>      <int> <dbl> <dbl> <int> <dbl> <dbl>
#> 1        1       104          1 0      9        0 0      9   
#> 2        1       104          1 0      3        0 0      3   
#> 3        1       104          2 0      5.67     0 0      5.67
#> 4        1       104          2 0.167  6.33     0 0.167  6.33
#> 5        1       104          2 0.667  6.83     0 0.667  6.83
#> 6        1       104          2 1.17   7        0 1.17   7

ggplot(coords) +
  geom_path(aes(x, y, 
                group = interaction(char_idx, stroke_idx), 
                colour = as.factor(char_idx)), 
            linewidth = 4) +
  geom_point(aes(x, y), color = 'yellow') + 
  theme_bw() +
  theme(legend.position = 'bottom') + 
  coord_equal()

The font with the best unicode coverage is the bitmap font unifont

library(lofifonts)

txt <- "二項分布\xF0\x9F\x8E\xB2の英語表記は\n「Binomial distribution」である。"

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Render quickly with built-in conversion
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bitmap_text_raster(txt, "unifont") |>
  plot()

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Bespoke plotting of the pixel locations
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
coords <- bitmap_text_coords(txt, "unifont")

ggplot(coords) +
  geom_tile(aes(x, y, fill = as.factor(char_idx)), na.rm = TRUE) +
  theme_void(10) +
  coord_equal() + 
  theme(legend.position = 'none')

bittermelon is a package which supports reading and manipulating many different types of bitmap font.

To use a font loaded with bittermelon is must first be convert to the lofi format which this package understands.

# Load font using "bittermelon"
filename <- system.file("fonts/fixed/4x6.yaff.gz", package = "bittermelon", mustWork = TRUE)
bmfont <- bittermelon::read_yaff(filename)

# Convert to lofi format
lofi <- convert_bm_font_to_lofi(bmfont)
lofi

#> [lofi bitmap font] 4 x 6. 919 codepoints.

# Layout the text and render to a raster
bitmap_text_raster('hello', font = lofi) |>
  plot()

library(lorem)

set.seed(1)
lorem::ipsum(1) |>
  strwrap(40) |>
  paste(collapse = "\n") |>
  bitmap_text_raster() |>
  plot()

library(lorem)
set.seed(1)

lorem::ipsum(1) |>
  strwrap(50) |>
  paste(collapse = "\n") |>
  vector_text_raster() |>
  plot(interpolate = TRUE)

A selection of the glyphs from each of the bitmap fonts

A selection of the glyphs from each of the vector fonts