adds 3D ( as pan and fade ) to ofxiOSSoundPlayer

ofxiOSSoundPlayer3D.h

//
//  ofxiOSSoundPlayer3D.h
//  iPhone_OSX_BuildTheo
//
//  Created by Theodore Watson on 5/9/13.
//
//

#pragma once

#include "ofxiOSSoundPlayer.h"

class ofxiOSSoundPlayer3D : public ofxiOSSoundPlayer{
    
    public:
        ofxiOSSoundPlayer3D();

        void setLocation(ofPoint pos);
        void setLocation(float x, float y, float z);
        void update();
        void setVolume(float vol);
    
        static void setListenerLocation(float x, float y, float z);
        static void setListenerLocation(ofPoint pos);

        static void setListenerLookAt(float x, float y, float z, ofPoint cameraUp);
        static void setListenerLookAt(ofPoint lookAt, ofPoint cameraUp);
    
        static void setListenerVelocity(ofPoint vel);
        static void setListenerVelocity(float x, float y, float z);
        static void setListenerGain(float gain);
        static void setReferenceDistance(float refDistance);
        static void setMaxDistance(float maxDist);

        ofPoint soundLocation;
        float originalVolume;

};

ofxiOSSoundPlayer3D.mm

//
//  ofxiOSSoundPlayer3D.cpp
//  iPhone_OSX_BuildTheo
//
//  Created by Theodore Watson on 5/9/13.
//
//

#include "ofxiOSSoundPlayer3D.h"

    
static float maxDistance = 3000.0;
static float minDistance = 5.0;
static float listenerGain = 1.0;

static ofPoint listenerPos(0, 0, 100);
static ofPoint listenerLookAt(0, 0, -1);
static ofPoint cameraUp(0, 1, 0);

ofxiOSSoundPlayer3D::ofxiOSSoundPlayer3D(){
    originalVolume = 1.0;
}

void ofxiOSSoundPlayer3D::setLocation(ofPoint pos){
    soundLocation = pos;
}

void ofxiOSSoundPlayer3D::setLocation(float x, float y, float z){
    setLocation(ofPoint(x, y, z));
}

void ofxiOSSoundPlayer3D::setVolume(float vol){
    originalVolume = vol;
    ofxiOSSoundPlayer::setVolume(vol);
}

void ofxiOSSoundPlayer3D::update(){

    ofPoint delta = soundLocation - listenerPos;
    float dist = delta.length();
    
    //first the pan
    ofPoint lookAtN = listenerLookAt.normalized();
    ofPoint leftRight = lookAtN.crossed(cameraUp);
    
    delta.normalize();
    float dotP = leftRight.dot(delta);
        
    ofxiOSSoundPlayer::setPan(dotP);
    
    //to simulate more sound going into a single ear when the sound is just on one side. 
    float gainComp = 1.0 + powf(fabs(dotP), 2) * 0.55;
    
    //now the gain
    float gain = powf(ofMap(dist, minDistance, maxDistance, 1, 0, true), 3) * originalVolume * listenerGain * gainComp;
    ofxiOSSoundPlayer::setVolume(gain);
}

//static methods

void ofxiOSSoundPlayer3D::setListenerLocation(ofPoint pos){
    listenerPos = pos; 
}

void ofxiOSSoundPlayer3D::setListenerLocation(float x, float y, float z){
    ofxiOSSoundPlayer3D::setListenerLocation(ofPoint(x, y, z));
}

void ofxiOSSoundPlayer3D::setListenerLookAt(ofPoint lookAt, ofPoint camUp){
    listenerLookAt = lookAt;
    cameraUp = camUp.normalized(); 
}

void ofxiOSSoundPlayer3D::setListenerLookAt(float x, float y, float z, ofPoint camUp){
    ofxiOSSoundPlayer3D::setListenerLookAt(ofPoint(x, y, z), camUp);
}


void ofxiOSSoundPlayer3D::setListenerVelocity(ofPoint vel){
    cout << " setListenerVelocity - not implemented " << endl;
}

void ofxiOSSoundPlayer3D::setListenerVelocity(float x, float y, float z){
    ofxiOSSoundPlayer3D::setListenerVelocity(ofPoint(x, y, z)); 
}

void ofxiOSSoundPlayer3D::setListenerGain(float gain){
    listenerGain = gain; 
}

void ofxiOSSoundPlayer3D::setReferenceDistance(float refDistance){
    minDistance = refDistance;
}

void ofxiOSSoundPlayer3D::setMaxDistance(float maxDist){
    maxDistance = maxDist;
}