Load a font file into MicroTeX

Loads an OTF/TTF font into MicroTeX's internal font registry. The font can then be used as a math font via the math_font parameter of latex_grob.

Usage

load_font(otf_path, clm_path = NULL)

Arguments

otf_path: Path to the OTF/TTF font file.
clm_path: Optional path to the companion .clm2 (or legacy .clm1) metrics file. If NULL (the default), load_font() searches for a file with the same stem as otf_path.

Value

Invisibly returns NULL.

Details

For standard usage, supply only otf_path. If a matching .clm2 file is present next to the OTF, it is used automatically. Otherwise you must generate one first (see Generating a CLM metrics file below).

Text fonts

Text inside \text{} is rendered using R's standard text-rendering system. Control the font with gp = gpar(fontfamily = "...") in latex_grob — no font loading required. This function is only needed for adding custom math fonts.

Generating a CLM metrics file

MicroTeX reads glyph metrics, the OpenType MATH table, and glyph outlines from a binary companion file (.clm2) rather than from the OTF directly. A converter script is bundled with the package at system.file("otf2clm.py", package = "gridmicrotex"). It requires FontForge's embedded Python (ffpython), since the standard Python does not ship the fontforge module.

Typical usage from a shell, for a single font:


ffpython otf2clm.py --single path/to/font.otf true out_dir

Or to convert every OTF in a directory:


ffpython otf2clm.py --batch in_dir true out_dir

The true argument tells the converter to embed glyph outlines (required for render_mode = "path"); pass false to generate a smaller .clm1 file suitable only for render_mode = "typeface". Run the script with no arguments to see the full usage including font-style flags.

Place the generated .clm2 file next to the OTF (same stem) so that load_font() finds it automatically, or pass it explicitly via clm_path.

Examples

# \donttest{
  # Load a custom math font from OTF (with a sibling .clm2 file):
  # load_font("path/to/font.otf")

  # Locate the bundled CLM converter:
  # system.file("otf2clm.py", package = "gridmicrotex")
# }