FontLoader

Unified font loading with automatic format detection.

Overview

Fontisan::FontLoader provides a unified interface for loading fonts in any supported format.

Class Methods

load(source)

Load a font from file path or IO.

# From file path
font = Fontisan::FontLoader.load('font.ttf')
font = Fontisan::FontLoader.load('font.otf')
font = Fontisan::FontLoader.load('font.pfb')
font = Fontisan::FontLoader.load('font.woff2')

# From IO
font = Fontisan::FontLoader.load(File.open('font.ttf'))

# From string
font = Fontisan::FontLoader.load(File.read('font.ttf', mode: 'rb'))

Parameters:

Name	Type	Description
source	String, IO	File path, IO object, or binary data

Returns: SfntFont, Type1Font, or Collection

Raises: Fontisan::FormatError if format is unsupported

detect_format(path)

Detect a font's on-disk format from its content (magic bytes). The file extension is ignored — a .ttc that actually contains a single OpenType-CFF font is reported as :otf.

format = Fontisan::FontLoader.detect_format('font.ttf')
# => :ttf

format = Fontisan::FontLoader.detect_format('font.otf')
# => :otf

format = Fontisan::FontLoader.detect_format('font.pfb')
# => :pfb

format = Fontisan::FontLoader.detect_format('font.pfa')
# => :pfa

Returns: Symbol (:ttf, :otf, :ttc, :otc, :woff, :woff2, :dfont, :pfa, :pfb) or nil if the format is not recognised.

Supported Formats

Symbol	Detection	Notes
:ttf	Magic bytes	TrueType
:otf	Magic bytes	OpenType / CFF
:ttc	Magic bytes	TrueType Collection
:otc	Magic bytes	OpenType Collection
:woff	Magic bytes	Web Open Font Format
:woff2	Magic bytes	Web Open Font Format 2
:pfb	Marker byte	Adobe Type 1 Binary
:pfa	Text header	Adobe Type 1 ASCII
:dfont	Magic bytes	Apple Data-Fork resource fork

Examples

Load with Error Handling

begin
  font = Fontisan::FontLoader.load(path)
  puts "Loaded: #{font.family_name}"
rescue Fontisan::FormatError => e
  puts "Unsupported format: #{e.message}"
rescue Errno::ENOENT => e
  puts "File not found: #{path}"
end

Batch Loading

fonts = Dir.glob('fonts/*.ttf').map do |path|
  Fontisan::FontLoader.load(path)
end

puts "Loaded #{fonts.length} fonts"

Detect and Load

path = 'unknown.dat'

format = Fontisan::FontLoader.detect_format(path)
if format
  puts "Detected format: #{format}"
  font = Fontisan::FontLoader.load(path)
else
  puts "Unknown format"
end