annotate scanpath.mm @ 0:c667dfe12d47

OK. Ther real deal.

/*
 *  scanpath.cpp
 *  springstructure
 *
 *  Created by Robert Tubb on 09/06/2011.
 *  Copyright 2011 __MyCompanyName__. All rights reserved.
 *
 */
#include <vector>
#include "scanpath.h"
#include "testApp.h"

//----------------------------------------------------------------
ScanPath::ScanPath() : maxElements(2048) {
	// construct an empty scanpath
	// an ' element ' consists of 1 lump and one spring

    
	numElements = 0; // numElements is a dynamic running count of elements when building - a bit crap
    springPath = new Spring*[maxElements];
    lumpPath = new Lump*[maxElements];
    
    framesPerSample = ofGetFrameRate()/SAMPLE_RATE;
    frameInterpolator = 0.0;
    currentLength = 0.0;
    restLength = 1.0; // ?

    scanMode = DISPLACEMENT;
    
    initWavetables();

}
//----------------------------------------------------------------
ScanPath::~ScanPath(){
	delete [] springPath;
    delete [] lumpPath;
    delete [] wavetableNew;
    delete [] wavetableOld;
    delete [] wavetableUpdate;
    cout << "destructed scanpath\n"; 
}

void ScanPath::clear(){
    for(int i = 0; i<numElements; i++){
        springPath[i]->removeFromScanPath();
        lumpPath[i]->removeFromScanPath();
    }
    numElements = 0;
    // cant work?
}
int ScanPath::howManyElements(){
    return numElements;
}
//----------------------------------------------------------------
void ScanPath::inscribe(double ax, double ay){
	// look at coordinates, add the closest lump and it's connecting string 
	// if we're further away from current lump
	
	// check end points of connecting springs, pick closest
}
void ScanPath::draw(){
    // draw the actual waveform in the corner

    int width = 768;
    int height = 128;
    double sampval = 0.0;
    int leftsampnum = 0;
    int rightsampnum = 0;
    float sampscale = 0.0, prevsampscale = 0.0, interp = 0.0;

     ofSetColor(0, 0, 0);
    double step = double(numElements)/width; // how much we are stepping thru wave per pixel
    for(int i = 0; i < width; i++){
        
        leftsampnum = floor(i * step); // basic nearest neighbour interpolation
        rightsampnum = ceil(i*step);
        interp  = (i*step)-leftsampnum;
        if(rightsampnum < numElements){
            sampval = (1 - interp)*wavetableNew[leftsampnum] + interp*wavetableNew[rightsampnum];
        }
        sampscale = (sampval * 700) + height/2.0; // centre and scale
        ofSetLineWidth(2);
        ofLine(sampscale, i, prevsampscale, i-1); // draw a line from pixel to pixel (?)
        prevsampscale = sampscale;
    }
    
}
void drawCubic(){
    
}
//----------------------------------------------------------------
// add spring
void ScanPath::addSpring(){
	// see add element
}
//----------------------------------------------------------------
// add lump
void ScanPath::addLump(){
    // see add element
}
//----------------------------------------------------------------
// add lump
double ScanPath::getTotalLength(){
    // for interesting modulations...
    currentLength = 0.0;
    for(int i = 0; i < numElements; i++){
        currentLength += springPath[i]->getLength();
    }
    return currentLength;
    
}
//----------------------------------------------------------------
void ScanPath::initWavetables(){
    wavetableNew = new double[maxElements];
    wavetableOld = new double[maxElements];
    wavetableUpdate = new double[maxElements];
    
    for(int i = 0; i < maxElements; i++){
        wavetableOld[i] = 0.0;
        wavetableNew[i] = 0.0;
        wavetableUpdate[i] = 0.0;
    }
    
}
//----------------------------------------------------------------
void ScanPath::addElement(Lump* aLump, Spring * aSpring){
    // insert ptr to the lump and spring into array
    if(numElements >= maxElements){
        cerr << "cannot add any more to scanpath - max elements: 2048\n";
        return;
    }
    lumpPath[numElements] = aLump;
    springPath[numElements] = aSpring;
    
    aLump->addToScanPath();
    aSpring->addToScanPath();
    
    numElements++;
}
//----------------------------------------------------------------
void ScanPath::updateWavetables(){
    // swap old , new
    double * temp;

    switch(scanMode){
        case DISPLACEMENT:
            // now fill with new values
            for(int i = 0; i < numElements; i++){

                wavetableUpdate[i] = lumpPath[i]->scanRadialDisplacement()/1.5;
                
            }
            break;
        case SPEED:
            for(int i = 0; i < numElements; i++){
                wavetableUpdate[i] = lumpPath[i]->scanLumpSpeed();
            }
            break;
        case SPRING_FORCE:
            for(int i = 0; i < numElements; i++){
                wavetableUpdate[i] = springPath[i]->getForceMag();
            }
            break;
        case YPOS:
            for(int i = 0; i < numElements; i++){
                wavetableUpdate[i] = lumpPath[i]->scanYPos();
            }
            break;
        default:
            break;
            
          
    }
 
    // reset the interp between frames
    if(audioAccessing){
        cout << "buffers swapped while update!\n";
    }
    updateAccessing = true;   
    temp = wavetableOld;
    wavetableOld = wavetableNew;
    wavetableNew = wavetableUpdate;
    wavetableUpdate = temp;
    updateAccessing = false;
    
    frameInterpolator = 0.0;
    framesPerSample = 2.0*ofGetFrameRate()/SAMPLE_RATE; // attempt to get a reasonable est. of how fast to interp
    
}
//----------------------------------------------------------------
// get next sample
double ScanPath::getNextSample(double aPhasor){
	// move along path, interpolating between points
    // move between frames too
    double alongPath = aPhasor*double(numElements);
    
    // indexes for interpolated points
    int n0 = floor(alongPath);
    int n1 = n0+1;
    if(n1 >= numElements){
        n1 = 0;
    }

    double frac = alongPath - double(n0);
    
    audioAccessing = true;
    if (updateAccessing){
        cout << "update is accessing while audio is\n";
    }
    double oldsample = (1 - frac) * wavetableOld[n0] + frac * wavetableOld[n1];
    
    double newsample = (1 - frac) * wavetableNew[n0] + frac * wavetableNew[n1];
    
    audioAccessing = false;
    
    frameInterpolator += framesPerSample;
    if(frameInterpolator >= 1.0){
        //cout << "frame interp > 1\n";
        frameInterpolator = 1.0; // just stays outputting new
    }
    
    double sample = (1 - frameInterpolator)*oldsample + frameInterpolator*newsample;
    //cout << sample << endl;
    // keep within the bounds of acceptability
    if(sample > 0.99){
       // cout << "OUCH\n";
        sample = 0.99;
    }else if(sample < -0.99){
        sample = -0.99;
    }
    return sample;
	
}
//----------------------------------------------------------------
// get next sample
double ScanPath::getNextSample(){
	// move along wavetable, no interpolation ie: length of path is pitch
    static int n = 0;
    double oldsample = wavetableOld[n];
    
    double newsample = wavetableNew[n]; 
    n++;
    if (n >= numElements){
        n = 0;
    }

    frameInterpolator += framesPerSample;
    if(frameInterpolator >= 1.0){
        //cout << "frame interp > 1\n";
        frameInterpolator = 1.0; // just stays outputting new
    }
    
    double sample = (1 - frameInterpolator)*oldsample + frameInterpolator*newsample;
    return sample*3.0;
	
}
//----------------------------------------------------------------
//----------------------------------------------------------------
// get next sample with cubic interpolation
double ScanPath::getNextSampleCubic(double aPhasor){
	// move along path, interpolating between points
    // move between frames too
    double alongPath = aPhasor*double(numElements);
    
    // indexes for interpolated points
    int n1 = floor(alongPath);
    
    int n0 = n1-1;
    if(n0 < 0){
        n0 = numElements;
    }
    int n2 = n1+1;
    if(n2 >= numElements){
        n2 = 0;
    }
    int n3 = n2+1;
    if(n3 >= numElements){
        n3 = 0;
    }
    double frac = alongPath - double(n0);
    double fracSquared = frac * frac;
    double fracCubed = fracSquared * frac;
    double a0,a1,a2,a3;
    //cout << n0 << endl;
    // cubic interp
    /*
     double y0,double y1,
     double y2,double y3,
     double mu)
     {
     double a0,a1,a2,a3,mu2;
     
     mu2 = mu*mu;
     a0 = y3 - y2 - y0 + y1;
     a1 = y0 - y1 - a0;
     a2 = y2 - y0;
     a3 = y1;
     
     return(a0*mu*mu2+a1*mu2+a2*mu+a3);
     */
    a0 = wavetableOld[n3] - wavetableOld[n2] - wavetableOld[n0] + wavetableOld[n1];
    a1 = wavetableOld[n0] - wavetableOld[n1] - a0; //  y0 - y1 - a0;
    a2 = wavetableOld[n2] - wavetableOld[n0]; // y2 - y0;
    a3 = wavetableOld[n1];
    
    double oldsample = a0*fracCubed + a1*fracSquared + a2*frac + a3;
    
    a0 = wavetableNew[n3] - wavetableNew[n2] - wavetableNew[n0] + wavetableNew[n1];
    a1 = wavetableNew[n0] - wavetableNew[n1] - a0; //  y0 - y1 - a0;
    a2 = wavetableNew[n2] - wavetableNew[n0]; // y2 - y0;
    a3 = wavetableNew[n1];
    
    double newsample = a0*fracCubed + a1*fracSquared + a2*frac + a3;
    
    frameInterpolator += framesPerSample;
    if(frameInterpolator >= 1.0){
        frameInterpolator = 1.0; // just stays outputting new
    }
    
    double sample = (1 - frameInterpolator)*oldsample + frameInterpolator*newsample;
    //cout << sample << endl;
    // keep within the bounds of acceptability
    
    // beef up
    sample = sample*3.0;
    
    if(sample > 0.99){
        sample = 0.99;
    }else if(sample < -0.99){
        sample = -0.99;
    }
    
    return sample;
	
}
//----------------------------------------------------------------