Techniques: The Base Set

Techniques: The Base Set

Techniques::Technique (in src/public/techniques/Technique.h) enumerates every performance modifier the engine can detect from MusicXML and emit as a keyswitch. The list is intentionally curated — every value carries weight in profile JSON and the editor’s keyswitch grid, so adding members costs real estate.

The Base Set (post-Phase 16)

Technique	Category	XML Element / Detection	Keyswitch Semantics
Muting	Sustained	<mute>palm</mute> or <mute>straight</mute>	Variant: Open/Semi-Closed/Closed/Dead
Vibrato	Sustained	<vibrato/> (with type attr in GP)	Held for the duration of the note
VibratoWTremBar	Sustained	GP-PI <vibratoWTremBar/> (with type attr)	Held for the duration of the note
NaturalHarmonic	PerNote	<harmonic><natural/></harmonic> in <technical>	Single-shot at the note’s onset
PinchHarmonic	PerNote	<harmonic/> without <natural/> in <technical>	Single-shot at the note’s onset
FingerPluckOpen	PerNote	<pluck> in <technical>	Single-shot at the note’s onset
FingerPluckDead	PerNote	<pluck> + <mute>straight</mute> or x-notehead	Single-shot at the note’s onset
TremoloPick	PerNote	<tremolo> in <ornaments>	Single-shot at the note’s onset
ThumbSlap	PerNote	GP-PI <bass-attack type="slap"/>	Single-shot at the note’s onset
Pop	PerNote	GP-PI <bass-attack type="pop"/>	Single-shot at the note’s onset
Tap	PerNote	<tap/>	Single-shot at the note’s onset
LhTap	PerNote	GP-PI <lhtapping/>	Single-shot at the note’s onset
ChokedNote	PerNote	<other-technical type="choked-note"/>	Single-shot at the note’s onset
PickScrape	PerNote	GP Slide property bit 0x40 (or 0x80 GP8 quirk)	Single-shot; routes to a dedicated keyswitch
AutoSlide	PerNote	GP Slide property bit 0x01 (Phase 22 addition)	“Host-decides-direction” legato slide-in
HammerOn	Span	<hammer-on type="start"/> … <.../type="stop"/>	Held from first note onset to last note end
PullOff	Span	<hammer-on> span where second pitch < first	Held from first note onset to last note end
Slur	Span	<slur type="start"/> … <.../type="stop"/>	Held; legato (hammer-on / pull-off by pitch)
Slide	Span	<slide type="start"/> … <.../type="stop"/>	Held; pitch glide along the run
SlideInFromAbove	PerNote	<plop/> in <articulations>	Single-shot at the note’s onset
SlideInFromBelow	PerNote	<scoop/> in <articulations>	Single-shot at the note’s onset
SlideOutDown	PerNote	<falloff/> in <articulations>	Single-shot at the note’s onset
SlideOutUp	PerNote	<doit/> in <articulations>	Single-shot at the note’s onset
Bend	Span	<bend> (single-note span)	Single-note span; pitch wheel envelope

kNumTechniques is the count of enumerators (currently 24) and is anchored by a static_assert. Techniques::getCategory(t) returns the Sustained / PerNote / Span classification used by the injector.

PickScrape and AutoSlide are only detected by the native Guitar Pro importers (.gp / .gpx) — MusicXML has no standard encoding for either, so the MusicXML parser leaves both flags clear.

Removed techniques

• LetRing — removed (no VST supports it via keyswitch)
• Scoop — consolidated into SlideInFromBelow
• ClosedPalmMute, SemiClosedPalmMute, DeadMute — consolidated as variant children of Muting

Adding a New Technique

The cadence is one commit per enum value, never a sweeping rewrite. Each new value lands with:

1. The enumerator added to Technique (in enumeration order matching its category bucket: Sustained -> PerNote -> Span).
2. kNumTechniques bumped; the static_assert anchors the new count.
3. An entry added to the kTable array in TechniqueCoding.cpp:
   • JSON name (PascalCase), XML name (kebab-case), human-readable label, category, and universal flag.
4. Parser detection rule — usually <other-technical type="..."> mapped via techniqueFromXML, or a dedicated <element/> match.
5. Test in tests/TechniqueParserTests.cpp driving a synthetic XML fixture that triggers the new detection path.
6. A row added to kExpectedEntries in tests/TechniqueCodingTests.cpp covering JSON / XML / category.
7. This document updated with the new row in the table above.