This Pi-powered protractor is intended to be used to calculate rotational angles in real time ... this is the sort of setup ...

Image caption, An obtuse angle is between 90° and 180°. Both of these angles are obtuse. Without using a protractor, a good estimate for the first angle is 135° because it is midway between 90 ...

The idea of the survey is to measure the angle of the flag as seen from point A and B using the two protractors. From this data we can determine the position and distance of the flag. If we make ...