Namespaces
namespace	detail

Classes
struct	Chord
	A chord "recipe" defining the required intervals relative to its root. More...

struct	DiatonicChord
	Contains the structure and generated symbol name of a diatonic chord. More...

struct	Scale
	Descriptor holding the name, pitch mask and chord tags for a musical scale. More...

Typedefs
using	NoteSet = std::uint16_t
	A 12-bit bitmask representing the 12 pitch-classes of the chromatic scale.

using	Degree = int
	Integer index used to select a degree inside standard diatonic representations (0-based).

Enumerations
enum class	ChordTag : std::uint16_t { MajorTriad = 1u << 0 , MinorTriad = 1u << 1 , DiminishedTriad = 1u << 2 , AugmentedTriad = 1u << 3 , Major7 = 1u << 4 , Dominant7 = 1u << 5 , Minor7 = 1u << 6 , HalfDim7 = 1u << 7 , Dim7 = 1u << 8 , Sus2Triad = 1u << 9 , Sus4Triad = 1u << 10 , Major9 = 1u << 11 , Dominant9 = 1u << 12 , Minor9 = 1u << 13 , Major11 = 1u << 14 , Dominant11 = 1u << 15 , All = 0xFFFFu }
	Bitmask flags describing chord "families" characteristic of a scale. More...

enum class	ChordLevel : std::uint8_t { TriadsOnly = 0 , Triads7 = 1 , Triads79 = 2 , Triads7911 = 3 , Triads791113 = 4 }
	Complexity level describing which extensions to generate for diatonic chords. More...

Functions
constexpr ChordTag	operator\| (ChordTag lhs, ChordTag rhs) noexcept
	Bitwise OR operator for ChordTag flags.

constexpr ChordTag	operator& (ChordTag lhs, ChordTag rhs) noexcept
	Bitwise AND operator for ChordTag flags (intersection).

constexpr bool	hasTags (ChordTag tags, ChordTag wanted) noexcept
	Tests whether `tags` contains ALL flags in `wanted`.

consteval NoteSet	makeMask (bool b0, bool b1, bool b2, bool b3, bool b4, bool b5, bool b6, bool b7, bool b8, bool b9, bool b10, bool b11) noexcept
	Build a NoteSet from 12 boolean flags (b0 = C, b1 = C#/Db, ... b11 = B).

consteval NoteSet	makeMask (std::initializer_list< int > degrees) noexcept
	Build a NoteSet from a list of semitone degrees.

constexpr std::string_view	noteName (int midi, int root=0) noexcept
	Returns a human-readable note name for the given MIDI note (0..127).

constexpr std::optional< int >	parseNote (std::string_view s) noexcept
	Parse a simple note name (no octave) into a pitch-class (0..11).

constexpr NoteSet	scaleAtRoot (NoteSet base, int root) noexcept
	Circularly rotate a NoteSet so it becomes rooted at a specific key.

constexpr std::array< int, 7 >	chordAtRootMidi (const Chord &c, int rootMidi, int inversion=0) noexcept
	Build MIDI note numbers for a chord recipe located at a specific root.

constexpr std::array< const Scale *, 16 >	scalesForChordMask (NoteSet chordMask) noexcept
	Reverse lookup: find up to 16 scales that fully contain `chordMask`.

constexpr std::array< const Scale *, 16 >	scalesForChord (const Chord &chord) noexcept
	Reverse lookup wrapper: find scales that can contain a specific Chord recipe.

constexpr DiatonicChord	diatonicChord (const Scale &sc, Degree degree, ChordLevel level) noexcept
	Generates the diatonic chord built upon a specific degree of a scale.

constexpr std::array< int, 7 >	diatonicChordToMidi (const DiatonicChord &c, int rootMidi) noexcept
	Convert a DiatonicChord's interval recipe into absolute MIDI notes.

constexpr std::optional< int >	parseNoteWithOctave (std::string_view note) noexcept
	Parse a note string containing an optional octave (e.g. "C#4", "C-1").

constexpr int	getOctaveFromNote (std::string_view note) noexcept
	Extract octave number from a note string. Supports negative octaves.

constexpr int	transposeByOctaves (int midi, int octaveDelta) noexcept
	Transpose a MIDI note by a discrete number of full octaves.

Variables
constexpr std::array< Scale, 61 >	allScales

constexpr std::array< std::string_view, 12 >	sharpNames

constexpr std::array< std::string_view, 12 >	flatNames

constexpr std::array< bool, 12 >	useSharpsForRoot

constexpr std::array< Chord, 15 >	allChords

Typedef Documentation

◆ Degree

dspark::harmony::Degree

Integer index used to select a degree inside standard diatonic representations (0-based).

Definition at line 51 of file HarmonyConstants.h.

◆ NoteSet

dspark::harmony::NoteSet

A 12-bit bitmask representing the 12 pitch-classes of the chromatic scale.

Bits 0..11 correspond to semitones above the root (0=C, 1=C#/Db, ..., 11=B). Fits perfectly in CPU registers for extremely fast subset/superset evaluations.

Definition at line 45 of file HarmonyConstants.h.

Enumeration Type Documentation

◆ ChordLevel

enum class dspark::harmony::ChordLevel : std::uint8_t

strong

Complexity level describing which extensions to generate for diatonic chords.

Enumerator
TriadsOnly	Generate base triads only (R-3-5).
Triads7	Generate up to 7th chords.
Triads79	Up to 9ths.
Triads7911	Up to 11ths.
Triads791113	Up to 13ths.

Definition at line 493 of file HarmonyConstants.h.

◆ ChordTag

enum class dspark::harmony::ChordTag : std::uint16_t

strong

Bitmask flags describing chord "families" characteristic of a scale.

Used to filter scales by chord type without computing intervals dynamically.

Note: The tags stored in allScales are REPRESENTATIVE of each scale's sonority (typically the root-degree triad and seventh), not an exhaustive list of every chord family constructible inside the scale. For exhaustive containment queries use scalesForChordMask(), which derives the answer from the pitch masks themselves.

Enumerator
MajorTriad	Contains a major triad (e.g., C-E-G).
MinorTriad	Contains a minor triad (e.g., C-Eb-G).
DiminishedTriad	Contains a diminished triad (e.g., C-Eb-Gb).
AugmentedTriad	Contains an augmented triad (e.g., C-E-G#).
Major7	Contains a major 7th chord.
Dominant7	Contains a dominant 7th chord.
Minor7	Contains a minor 7th chord.
HalfDim7	Contains a half-diminished 7th chord.
Dim7	Contains a fully-diminished 7th chord.
Sus2Triad	Contains a suspended-2 triad.
Sus4Triad	Contains a suspended-4 triad.
Major9	Contains a major 9th chord.
Dominant9	Contains a dominant 9th chord.
Minor9	Contains a minor 9th chord.
Major11	Contains a major 11th chord.
Dominant11	Contains a dominant 11th chord.
All	Convenience: all flags set.

Definition at line 70 of file HarmonyConstants.h.

Function Documentation

◆ chordAtRootMidi()

constexpr std::array< int, 7 > dspark::harmony::chordAtRootMidi	(	const Chord &	c,
		int	rootMidi,
		int	inversion = `0`
	)

constexprnoexcept

Build MIDI note numbers for a chord recipe located at a specific root.

Parameters

c	Chord definition to use.
rootMidi	MIDI note for chord root (0..127 typical).
inversion	Which chord tone to place in bass (0=root position, 1=first inversion...).

Returns: Array of 7 ints: valid MIDI numbers for present tones, unused slots = -1.

Definition at line 429 of file HarmonyConstants.h.

◆ diatonicChord()

constexpr DiatonicChord dspark::harmony::diatonicChord	(	const Scale &	sc,
		Degree	degree,
		ChordLevel	level
	)

constexprnoexcept

Generates the diatonic chord built upon a specific degree of a scale.

Parameters

sc	Scale definition (assumes root=C internally).
degree	The 0-based degree index inside the scale (0..6).
level	Which chord extensions to include.

Returns: A DiatonicChord object with the dynamically evaluated intervals and symbol.

Definition at line 532 of file HarmonyConstants.h.

◆ diatonicChordToMidi()

constexpr std::array< int, 7 > dspark::harmony::diatonicChordToMidi	(	const DiatonicChord &	c,
		int	rootMidi
	)

constexprnoexcept

Convert a DiatonicChord's interval recipe into absolute MIDI notes.

Parameters

c	The DiatonicChord object.
rootMidi	The MIDI note assigned as the root of the generated chord.

Returns: Array of 7 ints with valid MIDI notes, -1 for absent positions.

Definition at line 601 of file HarmonyConstants.h.

◆ getOctaveFromNote()

constexpr int dspark::harmony::getOctaveFromNote ( std::string_view note )

constexprnoexcept

Extract octave number from a note string. Supports negative octaves.

Parameters

note	String representation of the note (e.g. "C#5", "C-1").

Returns: Valid octave integer. Defaults to 4 if not present.

Definition at line 634 of file HarmonyConstants.h.

◆ hasTags()

constexpr bool dspark::harmony::hasTags	(	ChordTag	tags,
		ChordTag	wanted
	)

constexprnoexcept

Tests whether tags contains ALL flags in wanted.

Definition at line 114 of file HarmonyConstants.h.

◆ makeMask() [1/2]

consteval NoteSet dspark::harmony::makeMask	(	bool	b0,
		bool	b1,
		bool	b2,
		bool	b3,
		bool	b4,
		bool	b5,
		bool	b6,
		bool	b7,
		bool	b8,
		bool	b9,
		bool	b10,
		bool	b11
	)

noexcept

Build a NoteSet from 12 boolean flags (b0 = C, b1 = C#/Db, ... b11 = B).

Definition at line 142 of file HarmonyConstants.h.

◆ makeMask() [2/2]

consteval NoteSet dspark::harmony::makeMask ( std::initializer_list< int > degrees )

noexcept

Build a NoteSet from a list of semitone degrees.

Degree values are taken modulo 12. Negative degrees are ignored.

Definition at line 159 of file HarmonyConstants.h.

◆ noteName()

constexpr std::string_view dspark::harmony::noteName	(	int	midi,
		int	root = `0`
	)

constexprnoexcept

Returns a human-readable note name for the given MIDI note (0..127).

Parameters

midi	The MIDI note number.
root	The pitch-class of the key root (0..11) to decide enharmonic spelling.

Returns: std::string_view pointing to a static note name (e.g., "C#", "Db").

Definition at line 329 of file HarmonyConstants.h.

◆ operator&()

constexpr ChordTag dspark::harmony::operator&	(	ChordTag	lhs,
		ChordTag	rhs
	)

constexprnoexcept

Bitwise AND operator for ChordTag flags (intersection).

Returns: Flags present in both operands.

Definition at line 105 of file HarmonyConstants.h.

◆ operator|()

constexpr ChordTag dspark::harmony::operator\|	(	ChordTag	lhs,
		ChordTag	rhs
	)

constexprnoexcept

Bitwise OR operator for ChordTag flags.

Returns: Combination of both flags.

Definition at line 95 of file HarmonyConstants.h.

◆ parseNote()

constexpr std::optional< int > dspark::harmony::parseNote ( std::string_view s )

constexprnoexcept

Parse a simple note name (no octave) into a pitch-class (0..11).

Parameters

s	String containing note name (e.g., "C#", "Bb", "Fb").

Returns: Pitch-class 0..11 on success, std::nullopt on failure.

Definition at line 341 of file HarmonyConstants.h.

◆ parseNoteWithOctave()

constexpr std::optional< int > dspark::harmony::parseNoteWithOctave ( std::string_view note )

constexprnoexcept

Parse a note string containing an optional octave (e.g. "C#4", "C-1").

Parameters

note	String representation of the note.

Returns: Pitch-class (0..11) on success, or std::nullopt if format is invalid.

Definition at line 619 of file HarmonyConstants.h.

◆ scaleAtRoot()

constexpr NoteSet dspark::harmony::scaleAtRoot	(	NoteSet	base,
		int	root
	)

constexprnoexcept

Circularly rotate a NoteSet so it becomes rooted at a specific key.

Parameters

base	NoteSet defined with root = C.
root	Desired root as semitone offset from C (0..11).

Returns: New bitmask representing the transposed scale.

Definition at line 377 of file HarmonyConstants.h.

◆ scalesForChord()

constexpr std::array< const Scale *, 16 > dspark::harmony::scalesForChord ( const Chord & chord )

constexprnoexcept

Reverse lookup wrapper: find scales that can contain a specific Chord recipe.

Parameters

chord The Chord recipe object.

Returns: Array of pointers to compatible scales.

Definition at line 476 of file HarmonyConstants.h.

◆ scalesForChordMask()

constexpr std::array< const Scale *, 16 > dspark::harmony::scalesForChordMask ( NoteSet chordMask )

constexprnoexcept

Reverse lookup: find up to 16 scales that fully contain chordMask.

Parameters

chordMask A NoteSet representing the notes of the chord.

Returns: Array of pointers to compatible scales. Remaining entries are nullptr.

Definition at line 458 of file HarmonyConstants.h.

◆ transposeByOctaves()

constexpr int dspark::harmony::transposeByOctaves	(	int	midi,
		int	octaveDelta
	)

constexprnoexcept

Transpose a MIDI note by a discrete number of full octaves.

Parameters

midi	Original MIDI note number.
octaveDelta	Number of octaves to transpose (can be negative).

Returns: New MIDI note number.

Definition at line 665 of file HarmonyConstants.h.

Variable Documentation

◆ allChords

constexpr std::array<Chord, 15> dspark::harmony::allChords

inlineconstexpr

Initial value:

{{
        {"Major",      {0, 4, 7, -1, -1, -1, -1}},
        {"Minor",      {0, 3, 7, -1, -1, -1, -1}},
        {"Diminished", {0, 3, 6, -1, -1, -1, -1}},
        {"Augmented",  {0, 4, 8, -1, -1, -1, -1}},
        {"Major7",     {0, 4, 7, 11, -1, -1, -1}},
        {"Dominant7",  {0, 4, 7, 10, -1, -1, -1}},
        {"Minor7",     {0, 3, 7, 10, -1, -1, -1}},
        {"HalfDim7",   {0, 3, 6, 10, -1, -1, -1}},
        {"Dim7",       {0, 3, 6,  9, -1, -1, -1}},
        {"Sus2",       {0, 2, 7, -1, -1, -1, -1}},
        {"Sus4",       {0, 5, 7, -1, -1, -1, -1}},
        {"Major9",     {0, 4, 7, 11, 14, -1, -1}},
        {"Dominant9",  {0, 4, 7, 10, 14, -1, -1}},
        {"Minor9",     {0, 3, 7, 10, 14, -1, -1}},
        {"Major13",    {0, 4, 7, 11, 14, 17, 21}}
    }}

Definition at line 399 of file HarmonyConstants.h.

◆ allScales

constexpr std::array<Scale, 61> dspark::harmony::allScales

inlineconstexpr

Definition at line 222 of file HarmonyConstants.h.

◆ flatNames

constexpr std::array<std::string_view, 12> dspark::harmony::flatNames

inlineconstexpr

Initial value:

{
        "C","Db","D","Eb","E","F","Gb","G","Ab","A","Bb","B"
    }

Definition at line 309 of file HarmonyConstants.h.

◆ sharpNames

constexpr std::array<std::string_view, 12> dspark::harmony::sharpNames

inlineconstexpr

Initial value:

{
        "C","C#","D","D#","E","F","F#","G","G#","A","A#","B"
    }

Definition at line 306 of file HarmonyConstants.h.

◆ useSharpsForRoot

constexpr std::array<bool,12> dspark::harmony::useSharpsForRoot

inlineconstexpr

Initial value:

{
        1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1
    }

Definition at line 315 of file HarmonyConstants.h.

Namespaces

Classes

Typedefs

Enumerations

Functions

Variables

Typedef Documentation

◆ Degree

◆ NoteSet

Enumeration Type Documentation

◆ ChordLevel

◆ ChordTag

Function Documentation

◆ chordAtRootMidi()

◆ diatonicChord()

◆ diatonicChordToMidi()

◆ getOctaveFromNote()

◆ hasTags()

◆ makeMask() [1/2]

◆ makeMask() [2/2]

◆ noteName()

◆ operator&()

◆ operator|()

◆ parseNote()

◆ parseNoteWithOctave()

◆ scaleAtRoot()

◆ scalesForChord()

◆ scalesForChordMask()

◆ transposeByOctaves()

Variable Documentation

◆ allChords

◆ allScales

◆ flatNames

◆ sharpNames

◆ useSharpsForRoot