[chimerax-users] Question about creation of splines for alpha helix models

Dear Sir/Madam, My name is Shriya and I am an undergraduate research assistant at the Microsystems and Mechanobiology Lab at Carnegie Mellon University. I was wondering if you could help me with regard to how ChimeraX creates splines when modeling alpha helices. In particular, which atoms from the protein backbone are used as the points through which the spline is calculated? Thank you! Sincerely, Shriya Sivakumar