2.1 Functional Requirements

• Load font files in D3-TUI format (.d3f)
• Support multiple font faces simultaneously
• Character glyph lookup and metrics
• Font atlas management
• Fallback font support

2.2 Non-Functional Requirements

• Font loading time: < 50ms per font
• Font memory usage: < 512KB per font
• Glyph lookup: < 1μs per character

3. Font File Format