The software ReciPro makes various crystallographic calculations, visualizes a crystal structure, simulates diffraction patterns and TEM image, indexes diffraction spots, plots stereographic projection, and so on.

pyddt - a helpful tool for planning X-ray dynamical diffraction experiments and analyzing φ-scans

Shared C++/Eigen native library for the Crystallography suite: eigenvalue decomposition and matrix exponentials for dynamical diffraction, HRTEM image formation, pseudo-Voigt fitting, and histograms.