Dealing with Angle Wrap in c++ code

For completeness I’ll include both [0, 360) and [-180, 180) normalizations.

You will need #include <math.h>.

Normalize to [0,360):

double constrainAngle(double x){
    x = fmod(x,360);
    if (x < 0)
        x += 360;
    return x;
}

Normalize to [-180,180):

double constrainAngle(double x){
    x = fmod(x + 180,360);
    if (x < 0)
        x += 360;
    return x - 180;
}

The pattern should be easy enough to recognize to generalize to radians.

Angle Bisection:

double angleDiff(double a,double b){
    double dif = fmod(b - a + 180,360);
    if (dif < 0)
        dif += 360;
    return dif - 180;
}
double bisectAngle(double a,double b){
    return constrainAngle(a + angleDiff(a,b) * 0.5);
}

This should bisect an angle on the “smaller” side. (warning: not fully tested)