Using bitmap fonts

Bitmap font: included fonts

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"

Bitmap font functions

• bitmap_text_coords() returns a data.frame of pixel locations
• bitmap_text_matrix() returns a binary matrix with pixel locations set to 1
• bitmap_text_raster() returns a raster image of the text

Bitmap font: Rendering text

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()

Bitmap font: Bespoke pixel rendering

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 rectangels 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)
)