Guitar Tablature

Gen can output guitar tablature (TAB) in two formats: MusicXML for notation software, and ASCII for terminal display.

MusicXML TAB

Use compile_to_tab() for MusicXML with TAB clef:

use gen::compile_to_tab;

let source = r#"---
title: Guitar Riff
time-signature: 4/4
---
_E _G A B
^C ^D ^E ^G
"#;

let musicxml = compile_to_tab(source)?;

The output includes:

• TAB clef (6-line staff)
• String numbers (1-6)
• Fret positions
• Rhythm notation

ASCII TAB

For terminal display, use compile_to_ascii_tab():

use gen::compile_to_ascii_tab;

let source = "C D E F G A B ^C";
let tab = compile_to_ascii_tab(source)?;
println!("{}", tab);

Output:

e|------------------------0-|
B|------------------0-1-----|
G|------------0-2-----------|
D|------0-2-----------------|
A|--3-----------------------|
E|--------------------------|

Structured TAB Data

For programmatic access, use compile_to_tab_data():

use gen::compile_to_tab_data;

let source = "C D E F";
let tab = compile_to_tab_data(source)?;

for measure in &tab.measures {
    for note in &measure.notes {
        if let Some(pos) = note.position {
            println!("String {}, Fret {}", pos.string, pos.fret);
        }
    }
}

Fingering Algorithm

The TAB generator uses an intelligent fingering algorithm:

Priority Order

1. Open strings: Prefers notes that can be played open (fret 0)
2. Same string continuation: Keeps consecutive notes on the same string when possible
3. Look-ahead: Considers the next note to optimize hand position
4. Fret proximity: Minimizes hand movement between notes

Example

For the C major scale C D E F G A B ^C:

Note	String	Fret	Reasoning
C	5 (A)	3	3rd fret A string
D	4 (D)	0	Open D string (preferred)
E	4 (D)	2	Same string as previous
F	4 (D)	3	Same string continuation
G	3 (G)	0	Open G string
A	3 (G)	2	Same string
B	2 (B)	0	Open B string
^C	1 (e)	0	Open high E

Standard Tuning

The TAB generator assumes standard 6-string guitar tuning:

String	Note	MIDI
1 (e)	E4	64
2 (B)	B3	59
3 (G)	G3	55
4 (D)	D3	50
5 (A)	A2	45
6 (E)	E2	40

Playable Range

Notes are mapped to positions within a reasonable fret range:

Range	Fret Range
Low E (E2) to high E (E6)	Frets 0-24

Notes outside the guitar’s range will have no TAB position.

Example: Blues Riff

---
title: Blues Riff
time-signature: 4/4
key-signature: A
---

_A _A ^C/ _A/ _A/ ^C _A
_E _E _G/ _E/ _E/ _G _E

ASCII TAB output:

e|------------------------|------------------------|
B|------------------------|------------------------|
G|--2----2----2-2---------|------------------------|
D|------------------2-----|--2----2----2-2---------|
A|--0----0--------0-------|------------------2-----|
E|------------------------|--0----0--------0-------|

Limitations

• Standard tuning only: No alternate tunings currently supported
• Single notes: Chords are rendered as arpeggios (one note per position)
• No techniques: Bends, slides, hammer-ons, and pull-offs are not notated
• Range: Notes outside E2-E6 cannot be positioned

Tips

1. Write in guitar-friendly ranges: Use _ and ^ to keep notes in the guitar’s range
2. Consider open strings: Melodies using open string notes (E, A, D, G, B) are easier to play
3. Check the output: Review ASCII TAB to ensure playability before sharing

CLI Usage

From the command line:

# MusicXML TAB
cargo run -- --tab score.gen > score_tab.musicxml

# ASCII TAB
cargo run -- --ascii-tab score.gen