YKSConverter Rust Implementation

Modern Rust port of the MML to MIDI converter with 100% binary compatibility with the C++ version.

Building

cargo build --release

Usage

Command Line Tool

Clone and run directly:

git clone https://github.com/rajephon/YKSConverter.git
cd YKSConverter/rust
cargo run --bin yks_converter -- "MML@t120l4cdefg,,;"

This generates output.midi in the current directory.

More examples:

# Simple melody
cargo run --bin yks_converter -- "MML@t120l4cdefg,,;"

# Complex multi-track piece  
cargo run --bin yks_converter -- "MML@t190l8cdefgab>c4.,l8<cdefgab>c4.,l8>cdefgab>c4.;"

Library Usage

Single Track Example

use yks_converter::YksConverter;

fn main() {
    let mml = "MML@t190l8cdefgab>c4.,l8<cdefgab>c4.,l8>cdefgab>c4.;";
    let converter = YksConverter::new(mml.to_string(), 1);
    
    if let Some(buffer) = converter.to_buffer() {
        std::fs::write("output.midi", buffer.as_slice()).unwrap();
    }
}

Multi-Track Example

use yks_converter::YksConverter;

fn main() {
    let mml_tracks = vec![
        "MML@t180l8ccccccc4,l8eeeeeee4,l8ggggggg4;".to_string(),
        "MML@t180l8>ccccccc4,l8>eeeeeee4,l8>ggggggg4;".to_string(),
    ];
    let instruments = vec![26, 74]; // MIDI instrument codes
    
    let converter = YksConverter::new_multi(mml_tracks, instruments);
    if let Some(buffer) = converter.to_buffer() {
        std::fs::write("ensemble.midi", buffer.as_slice()).unwrap();
    }
}

Adding to Your Project

Add to your Cargo.toml:

[dependencies]
yks_converter = "0.1.0"

Or use cargo:

cargo add yks_converter

Testing

Run the comprehensive test suite:

cargo test                           # All tests
cargo test -- --nocapture          # With debug output
cargo test binary_compatibility    # Binary compatibility test

Test Coverage

• ✅ MML regex parsing
• ✅ Single note parsing
• ✅ Multi-note sequences
• ✅ Length tokens (l8, l4, etc.)
• ✅ Octave changes (<, >)
• ✅ Dotted notes (4.)
• ✅ Tempo changes (t190)
• ✅ Multi-track support
• ✅ 100% Binary compatibility with C++

Dependencies

• regex - MML pattern matching
• byteorder - MIDI binary format handling

Architecture

This Rust implementation mirrors the C++ architecture:

• YksConverter: Main converter struct
• Mf2tt2mf: MML parsing and MIDI track building
• TrackBuilder: MIDI track construction
• TrackEvent: Trait for MIDI event types
  • MetaText, Tempo, SysEx
  • ProgramChange, ControlChange
  • NoteOn, NoteOff, EndOfTrack
• ByteBuffer: Binary MIDI data handling with big-endian support

Binary Compatibility

The Rust version produces identical MIDI output to the C++ version:

• Same timing calculations (384 ticks per whole note)
• Same velocity values (8 * volume)
• Same MIDI event encoding
• Verified with comprehensive binary comparison tests

Performance

cargo bench                  # Run benchmarks
cargo build --release       # Optimized build