X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;f=scherzo.c;h=89a93010b9b6c54585c53ffb54145b5925d0a031;hb=99dc6bdb0dba7a014e41783da6e83046a2f2973e;hp=098008930e4d4d77b4dd21ec82ad40ca52d19554;hpb=fc6b1da08cd8552050d2669363a85e405f19736d;p=scherzo diff --git a/scherzo.c b/scherzo.c index 0980089..89a9301 100644 --- a/scherzo.c +++ b/scherzo.c @@ -450,10 +450,15 @@ static int _modified_degree_to_half_steps (const modified_degree_t *degree) { int half_steps; + int scale_degree = degree->degree; + + /* Restrict to actual degrees within a scale. */ + if (scale_degree > 7) + scale_degree = (scale_degree % 8) + 1; /* Number of half steps from root to specified degree within a * diatonic scaled. */ - switch (degree->degree) { + switch (scale_degree) { case 1: half_steps = 0; break; @@ -489,55 +494,46 @@ _chord_signature_matches (analyzed_note_t *notes, int num_notes, modified_degree_t *degrees, int num_degrees, - int *inversion_ret, + int inversion, score_pitch_t *root) { -#define MAX_DEGREES 4 +#define MAX_DEGREES 5 int relative_pitches[MAX_DEGREES]; - int inversion, max_inversions; int i, root_index; assert (num_degrees <= MAX_DEGREES); if (num_notes != num_degrees) - return 0; + return 0; - max_inversions = num_degrees; + if (inversion >= num_degrees) + return 0; /* We never spell simple intervals as inversions. */ - if (num_degrees == 2) - max_inversions = 1; - - for (inversion = 0; inversion < max_inversions; inversion++) { - for (i = 0; i < num_degrees; i++) { - /* The num_degrees is in the addition just to ensure all - * inputs to the modulus operator remain positive. */ - int index = (i + num_degrees - inversion) % num_degrees; - - /* Again, adding a 12 to keep things positive. */ - relative_pitches[index] = - (12 + - _modified_degree_to_half_steps (°rees[i]) - - _modified_degree_to_half_steps (°rees[inversion])) % 12; + if (num_degrees == 2 && inversion > 0) + return 0; + + for (i = 0; i < num_degrees; i++) { + /* The num_degrees is in the addition just to ensure all + * inputs to the modulus operator remain positive. */ + int index = (i + num_degrees - inversion) % num_degrees; + + /* Again, adding a 12 to keep things positive. */ + relative_pitches[index] = + (12 + + _modified_degree_to_half_steps (°rees[i]) - + _modified_degree_to_half_steps (°rees[inversion])) % 12; - } - - for (i = 0; i < num_notes; i++) - if (notes[i].relative_pitch != relative_pitches[i]) - goto NEXT_INVERSION; - - root_index = (num_notes - inversion) % num_notes; - *root = notes[root_index].note->pitch; + } - *inversion_ret = inversion; + for (i = 0; i < num_notes; i++) + if (notes[i].relative_pitch != relative_pitches[i]) + return 0; - return 1; + root_index = (num_notes - inversion) % num_notes; + *root = notes[root_index].note->pitch; - NEXT_INVERSION: - ; - } - - return 0; + return 1; } static const char * @@ -670,22 +666,67 @@ scherzo_analyze_chord (scherzo_t *scherzo) #define PUS "" struct { modified_degree_t degrees[3]; const char *name; } triads[] = { + { {{1, 0}, {3, +1}, {5, 0}}, "sus" }, { {{1, 0}, {3, 0}, {5, +1}}, SUP "+" PUS }, { {{1, 0}, {3, 0}, {5, 0}}, "" }, { {{1, 0}, {3, -1}, {5, 0}}, "m" }, - { {{1, 0}, {3, -1}, {5, -1}}, "°" } + { {{1, 0}, {3, -1}, {5, -1}}, "°" }, + { {{1, 0}, {2, 0}, {5, 0}}, "msus2" } }; - struct { modified_degree_t degrees[4]; const char *name; } sevenths[] = { + struct { modified_degree_t degrees[4]; const char *name; } tetrachords[] = { + /* Sixth chords */ + { {{1, 0}, {3, +1}, {5, 0}, {6, 0}}, "sus" SUP "6" PUS }, + { {{1, 0}, {3, 0}, {5, 0}, {6, 0}}, "6" }, + { {{1, 0}, {3, -1}, {5, 0}, {6, 0}}, "m6" }, + { {{1, 0}, {2, 0}, {5, 0}, {6, 0}}, "msus2" SUP "6" PUS }, + /* Seventh chords */ + { {{1, 0}, {3, +1}, {5, 0}, {7, 0}}, "sus" SUP "M7" PUS }, + { {{1, 0}, {3, +1}, {5, 0}, {7, -1}}, "sus" SUP "7" PUS }, + { {{1, 0}, {3, +1}, {5, -1}, {7, -1}}, "sus" SUP "7♭5" PUS }, { {{1, 0}, {3, 0}, {5, +1}, {7, 0}}, SUP "+M7" PUS }, { {{1, 0}, {3, 0}, {5, +1}, {7, -1}}, SUP "+7" PUS }, { {{1, 0}, {3, 0}, {5, 0}, {7, 0}}, "M7" }, { {{1, 0}, {3, 0}, {5, 0}, {7, -1}}, "7" }, + { {{1, 0}, {3, 0}, {5, -1}, {7, -1}}, SUP "7♭5" PUS }, { {{1, 0}, {3, -1}, {5, 0}, {7, 0}}, "m" SUP "M7" PUS }, { {{1, 0}, {3, -1}, {5, 0}, {7, -1}}, "m7" }, { {{1, 0}, {3, -1}, {5, -1}, {7, 0}}, "°" SUP "M7" PUS }, { {{1, 0}, {3, -1}, {5, -1}, {7, -1}}, "𝆩" SUP "7" PUS }, - { {{1, 0}, {3, -1}, {5, -1}, {7, -2}}, "°" SUP "7" PUS } + { {{1, 0}, {3, -1}, {5, -1}, {7, -2}}, "°" SUP "7" PUS }, + { {{1, 0}, {2, 0}, {5, 0}, {7, 0}}, "msus2" SUP "M7" PUS }, + { {{1, 0}, {2, 0}, {5, 0}, {7, -1}}, "msus2" SUP "7" PUS }, + { {{1, 0}, {2, 0}, {5, -1}, {7, 0}}, "msus2°" SUP "M7" PUS }, + { {{1, 0}, {2, 0}, {5, -1}, {7, -1}}, "msus2𝆩" SUP "7" PUS }, + { {{1, 0}, {2, 0}, {5, -1}, {7, -2}}, "msus2°" SUP "7" PUS }, + /* Ninth chords voiced with no 5th */ + { {{1, 0}, {9, 0}, {3, 0}, {7, 0}}, "M9" }, + { {{1, 0}, {9, 0}, {3, 0}, {7, -1}}, "9" }, + { {{1, 0}, {9, 0}, {3, -1}, {7, 0}}, "m" SUP "M9" PUS }, + { {{1, 0}, {9, 0}, {3, -1}, {7, -1}}, "m9" }, + { {{1, 0}, {9, -1}, {3, -1}, {7, -1}}, "m♭9" }, + }; + + /* The sorting here is funny to keep the array in degree order + * after reducing each degree to an actual scale degree, (9 -> 2, + * 11 -> 4, 13 -> 6) */ + struct { modified_degree_t degrees[5]; const char *name; } pentachords[] = { + { {{1, 0}, {9, 0}, {3, 0}, {5, +1}, {7, 0}}, SUP "+M9" PUS }, + { {{1, 0}, {9, 0}, {3, 0}, {5, +1}, {7, -1}}, SUP "+9" PUS }, + { {{1, 0}, {9, 0}, {3, 0}, {5, 0}, {7, 0}}, "M9" }, + { {{1, 0}, {9, 0}, {3, 0}, {5, 0}, {7, -1}}, "9" }, + { {{1, 0}, {9, 0}, {3, -1}, {5, 0}, {7, 0}}, "m" SUP "M9" PUS }, + { {{1, 0}, {9, 0}, {3, -1}, {5, 0}, {7, -1}}, "m9" }, + { {{1, 0}, {9, -1}, {3, -1}, {5, 0}, {7, -1}}, "m♭9" }, + { {{1, 0}, {9, 0}, {3, -1}, {5, -1}, {7, -1}}, "𝆩" SUP "9" PUS }, + + /* FIXME: I don't have names for these last three after + * dropping the 5th from the voicing. That suggests to me that + * I'm missing names for these with a perfect 5th in the list + * above. */ + { {{1, 0}, {9, -1}, {3, -1}, {5, -1}, {7, -1}}, "𝆩" SUP "♭9" PUS }, + { {{1, 0}, {9, 0}, {3, -1}, {5, -1}, {7, -2}}, "°" SUP "9" PUS }, + { {{1, 0}, {9, -1}, {3, -1}, {5, -1}, {7, -2}}, "°" SUP "♭9" PUS }, }; if (scherzo->chord) { @@ -750,52 +791,66 @@ scherzo_analyze_chord (scherzo_t *scherzo) } } - switch (num_notes) { - case 1: - for (i = 0; i < ARRAY_SIZE (octaves); i++) { - if (_chord_signature_matches (notes, num_notes, - octaves[i].degrees, 1, - &inversion, &root)) - { - chord_name = octaves[i].name; - break; + for (inversion = 0; inversion < 4; inversion++) { + switch (num_notes) { + case 1: + for (i = 0; i < ARRAY_SIZE (octaves); i++) { + if (_chord_signature_matches (notes, num_notes, + octaves[i].degrees, 1, + inversion, &root)) + { + chord_name = octaves[i].name; + goto CHORD_NAME_KNOWN; + } } - } - break; - case 2: - for (i = 0; i < ARRAY_SIZE (intervals); i++) { - if (_chord_signature_matches (notes, num_notes, - intervals[i].degrees, 2, - &inversion, &root)) - { - chord_name = intervals[i].name; - break; + break; + case 2: + for (i = 0; i < ARRAY_SIZE (intervals); i++) { + if (_chord_signature_matches (notes, num_notes, + intervals[i].degrees, 2, + inversion, &root)) + { + chord_name = intervals[i].name; + goto CHORD_NAME_KNOWN; + } } - } - break; - case 3: - for (i = 0; i < ARRAY_SIZE (triads); i++) { - if (_chord_signature_matches (notes, num_notes, - triads[i].degrees, 3, - &inversion, &root)) - { - chord_name = triads[i].name; - break; + break; + case 3: + for (i = 0; i < ARRAY_SIZE (triads); i++) { + if (_chord_signature_matches (notes, num_notes, + triads[i].degrees, 3, + inversion, &root)) + { + chord_name = triads[i].name; + goto CHORD_NAME_KNOWN; + } } - } - break; - case 4: - for (i = 0; i < ARRAY_SIZE(sevenths); i++) { - if (_chord_signature_matches (notes, num_notes, - sevenths[i].degrees, 4, - &inversion, &root)) - { - chord_name = sevenths[i].name; - break; + break; + case 4: + for (i = 0; i < ARRAY_SIZE (tetrachords); i++) { + if (_chord_signature_matches (notes, num_notes, + tetrachords[i].degrees, 4, + inversion, &root)) + { + chord_name = tetrachords[i].name; + goto CHORD_NAME_KNOWN; + } } + break; + case 5: + for (i = 0; i < ARRAY_SIZE (pentachords); i++) { + if (_chord_signature_matches (notes, num_notes, + pentachords[i].degrees, 5, + inversion, &root)) + { + chord_name = pentachords[i].name; + goto CHORD_NAME_KNOWN; + } + } + break; } - break; } + CHORD_NAME_KNOWN: if (chord_name) { if (inversion) {