Type 1 (PFB/PFA)

Adobe Type 1 fonts are legacy PostScript fonts.

Overview

• Curve Type: Cubic Bézier
• Hinting: PostScript hints
• Formats: PFB (binary), PFA (ASCII)

File Formats

Format	Extension	Description
PFB	.pfb	Binary format
PFA	.pfa	ASCII format

Structure

Type 1 fonts contain:

1. Font Dictionary — Font info, encoding
2. Private Dictionary — Hinting parameters
3. CharStrings — Glyph outlines
4. Subroutines — Reusable outline segments

Encryption

Type 1 fonts use encryption:

Section	Key
eexec	55665
CharStrings	4330

Fontisan handles decryption automatically.

Loading

font = Fontisan::FontLoader.load('font.pfb')

# Access font info
puts "Family: #{font.family_name}"
puts "Glyphs: #{font.glyph_count}"

CharStrings

# Type 1 CharStrings use operators
# hstem, vstem, moveto, lineto, curveto, etc.

font.charstrings.each do |glyph_name, charstring|
  puts "#{glyph_name}: #{charstring.length} bytes"
end

seac Composites

Type 1 supports composite characters via seac:

# Example: é = e + acute accent
# seac references two glyphs by name

When converting to CFF, seac must be expanded (CFF doesn't support it).

Converting

Type 1 to OTF

fontisan convert font.pfb --to otf --output font.otf

Type 1 to TTF

fontisan convert font.pfb --to ttf --output font.ttf

With Unicode Generation

# Generate Unicode mappings from glyph names
fontisan convert font.pfb --to otf --generate-unicode --output font.otf

Characteristics

Advantages

• Print workflows — PostScript native
• High quality — Professional fonts
• Cubic curves — Fewer points

Limitations

• Legacy format — Modern systems prefer OTF
• Limited Unicode — Requires glyph name mapping
• No native Unicode — Must be generated

seac Expansion

seac (Standard Encoding Accented Character) must be expanded for CFF:

# Fontisan automatically expands seac during conversion
options = Fontisan::ConversionOptions.new(
  opening: { decompose_composites: true }
)