ofPolyline line = ...
vector<ofPoint> vertices = line.getVertices(); // the set of points
bool closed = false;
double tolerance = 10;
vector<BezPoint> bezier = ofxPathFitter::simplify(vertices, closed, tolerance); // creates the Bezier curve through the points

bezier = ofxPathFitter::simplify(line, tolerance);

ofPoint point; // the point
ofPoint handleIn; // the first control point
ofPoint handleOut // the second control point

BezPoint s = ofxPathFitter::handlesAbsolute(bezier[i]);

vector<BezPoint> bezierAbs = ofxPathFitter::handlesAbsolute(bezier);