library/repos/AmalgamatedHarmonics/src/Core.cpp

#include "Core.hpp"

#include <iostream>

float Core::getPitchFromVolts(float inVolts, float inRoot, float inScale, int *outRoot, int *outScale, int *outNote, int *outDegree) {
	
	// get the root note and scale
	int currRoot = getKeyFromVolts(inRoot);
	int currScale = getScaleFromVolts(inScale);

	if (debug && stepX % poll == 0) {
		std::cout << "QUANT " << stepX << " Root in: " << inRoot << " Root out: " << currRoot<< " Scale in: " << inScale << " Scale out: " << currScale << std::endl;
	}	
	
	float outVolts = getPitchFromVolts(inVolts, currRoot, currScale, outNote, outDegree);
	
	*outRoot = currRoot;
	*outScale = currScale;
	
	return outVolts;
 
}

float Core::getPitchFromVolts(float inVolts, int currRoot, int currScale, int *outNote, int *outDegree) {
	
	int *curScaleArr;
	int notesInScale = 0;
	switch (currScale){
		case SCALE_CHROMATIC:		curScaleArr = ASCALE_CHROMATIC;			notesInScale=LENGTHOF(ASCALE_CHROMATIC); break;
		case SCALE_IONIAN:			curScaleArr = ASCALE_IONIAN;			notesInScale=LENGTHOF(ASCALE_IONIAN); break;
		case SCALE_DORIAN:			curScaleArr = ASCALE_DORIAN;			notesInScale=LENGTHOF(ASCALE_DORIAN); break;
		case SCALE_PHRYGIAN:		curScaleArr = ASCALE_PHRYGIAN;			notesInScale=LENGTHOF(ASCALE_PHRYGIAN); break;
		case SCALE_LYDIAN:			curScaleArr = ASCALE_LYDIAN;			notesInScale=LENGTHOF(ASCALE_LYDIAN); break;
		case SCALE_MIXOLYDIAN:		curScaleArr = ASCALE_MIXOLYDIAN;		notesInScale=LENGTHOF(ASCALE_MIXOLYDIAN); break;
		case SCALE_AEOLIAN:			curScaleArr = ASCALE_AEOLIAN;			notesInScale=LENGTHOF(ASCALE_AEOLIAN); break;
		case SCALE_LOCRIAN:			curScaleArr = ASCALE_LOCRIAN;			notesInScale=LENGTHOF(ASCALE_LOCRIAN); break;
		case SCALE_MAJOR_PENTA:		curScaleArr = ASCALE_MAJOR_PENTA;		notesInScale=LENGTHOF(ASCALE_MAJOR_PENTA); break;
		case SCALE_MINOR_PENTA:		curScaleArr = ASCALE_MINOR_PENTA;		notesInScale=LENGTHOF(ASCALE_MINOR_PENTA); break;
		case SCALE_HARMONIC_MINOR:	curScaleArr = ASCALE_HARMONIC_MINOR;	notesInScale=LENGTHOF(ASCALE_HARMONIC_MINOR); break;
		case SCALE_BLUES:			curScaleArr = ASCALE_BLUES;				notesInScale=LENGTHOF(ASCALE_BLUES); break;
		default: 					curScaleArr = ASCALE_CHROMATIC;			notesInScale=LENGTHOF(ASCALE_CHROMATIC);
	}

	// get the octave
	int octave = floor(inVolts);
	float closestVal = 10.0;
	float closestDist = 10.0;
	int noteFound = 0;

	if (debug && stepX % poll == 0) {
		std::cout << "QUANT Octave: " << octave << " Scale: " << scaleNames[currScale] << " Root: " << noteNames[currRoot] << std::endl;
	}

	float octaveOffset = 0;
	if (currRoot != 0) {
		octaveOffset = (12 - currRoot) / 12.0;
	}
	
	if (debug && stepX % poll == 0) {
		std::cout << "QUANT Octave: " << octave << " currRoot: " << currRoot << " -> Offset: " << octaveOffset << " inVolts: " << inVolts << std::endl;
	}
		
	float fOctave = (float)octave - octaveOffset;	
	int scaleIndex = 0;
	int searchOctave = 0;
	
	do { 

		int degree = curScaleArr[scaleIndex]; // 0 - 11!
		float fVoltsAboveOctave = searchOctave + degree / 12.0;
		float fScaleNoteInVolts = fOctave + fVoltsAboveOctave;
		float distAway = fabs(inVolts - fScaleNoteInVolts);

		if (debug && stepX % poll == 0) {
			std::cout << "QUANT input: " << inVolts
			<< " index: " << scaleIndex
			<< " root: " << currRoot
			<< " octave: " << fOctave
			<< " degree: " << degree
			<< " V above O: " << fVoltsAboveOctave
			<< " note in V: " << fScaleNoteInVolts
			<< " distance: " << distAway
			<< std::endl;
		}

		// Assume that the list of notes is ordered, so there is an single inflection point at the minimum value
		if (distAway >= closestDist){
			break;
		} else {
			// Let's remember this
			closestVal = fScaleNoteInVolts;
			closestDist = distAway;
		}
		
		scaleIndex++;
		
		if (scaleIndex == notesInScale - 1) {
			scaleIndex = 0;
			searchOctave++;
		}

	} while (true);

	if(scaleIndex == 0) {
		noteFound = notesInScale - 2; // NIS is a count, not index
	} else {
		noteFound = scaleIndex - 1;
	}

	if (debug && stepX % poll == 0) {
		std::cout << "QUANT NIS: " << notesInScale <<  " scaleIndex: " << scaleIndex << " NF: " << noteFound << std::endl;
	}
	
	int currNote = (currRoot + curScaleArr[noteFound]) % 12; // So this is the nth note of the scale; 
	// case in point, V=0, Scale = F#m returns the 6th note, which should be C#

	if (debug && stepX % poll == 0) {
		// Dump the note and degree, mod the size in case where we have wrapped round

		std::cout << "QUANT Found index in scale: " << noteFound << ", currNote: "  << currNote;
		std::cout << " This is scale note: "  << curScaleArr[noteFound] << " (Interval: " << intervalNames[curScaleArr[noteFound]] << ")";
		std::cout << ": " << inVolts << " -> " << closestVal << std::endl;

	}

	*outNote = currNote;
	*outDegree = curScaleArr[noteFound];
	
	return closestVal;
 
}


void Core::getRootFromMode(int inMode, int inRoot, int inTonic, int *currRoot, int *quality) {
	
	*quality = ModeQuality[inMode][inTonic];

	int positionRelativeToStartOfScale = tonicIndex[inMode + inTonic];
	int positionStartOfScale = scaleIndex[inMode];
	
	// FIXME should be mapped into the Circle of Fifths??	
	*currRoot = inRoot + noteIndex[positionStartOfScale + positionRelativeToStartOfScale]; 
 	
 	if (*currRoot < 0) {
 		*currRoot += 12;
 	}
	
 	if (*currRoot > 11) {
 		*currRoot -= 12;
 	}
 
	// Quantizer q;
	//
	// std::cout << "Mode: " << inMode
	// 	<< " Root: " << q.noteNames[inRoot]
	// 	<< " Tonic: " << q.tonicNames[inTonic]
	// 	<< " Scale Pos: " << positionStartOfScale
	// 	<< " Rel Pos: " <<  positionRelativeToStartOfScale
	// 	<< " Note Index: " << positionStartOfScale + positionRelativeToStartOfScale
	// 	<< " Note: " << noteIndex[positionStartOfScale + positionRelativeToStartOfScale]
	// 	<< " Offset: " << ModeOffset[inMode][inTonic]
	// 	<< " Output: " << *currRoot
	// 	<< " " << q.noteNames[*currRoot]
	// 	<< std::endl;
 }
 
 Core & CoreUtil() {
     static Core core;
     return core;
 }
 
 //	http://c-faq.com/lib/gaussian.html
 double Core::gaussrand() {
 	static double U, V;
 	static int phase = 0;
 	double Z;

 	if(phase == 0) {
 		U = (rand() + 1.) / (RAND_MAX + 2.);
 		V = rand() / (RAND_MAX + 1.);
 		Z = sqrt(-2 * log(U)) * sin(2 * M_PI * V);
 	} else
 		Z = sqrt(-2 * log(U)) * cos(2 * M_PI * V);

 	phase = 1 - phase;

 	return Z;
 }
 
 int Core::ipow(int base, int exp) {
     int result = 1;
     while (exp)
     {
         if (exp & 1)
             result *= base;
         exp >>= 1;
         base *= base;
     }

     return result;
 }