double xp = cosTheta * x - sinTheta * y; // translate point by thetaIncrement
double yp = sinTheta * x + cosTheta * y;
lineAbs (xCent + xp, yCent + yp);
double xp = cosTheta * x - sinTheta * y; // translate point by thetaIncrement
double yp = sinTheta * x + cosTheta * y;
lineAbs (xCent + xp, yCent + yp);