BornAgain comes with a graphical user interface (GUI). Based on the library Qt6, it has a native look and feel under all three supported operating systems. It allows users to view experimental and simulated data, to set up and parameterize physical models, and to run fits.
A graphical sample editor allows users to set up multilayer models. Model components like embedded particles or inter-particle correlation functions are represented by groupboxes with editable fields. Simultaneously, the real-space structure of the sample, or any of its components, can be shown in an interactive 3D visualization. This provides users with feedback as to whether the model, constructed in abstract terms in the sample editor, corresponds to their actual intentions. Moreover, a real-space representation can be helpful when communicating scientific results to audiences that are not familiar with the reciprocal-space thinking of scattering practitioners.
All model parameters can also be seen and set from a tree view. To explore their impact upon the simulated GISAS pattern, it is possible to modify parameter values with sliders. Unless the model is excessively computing intensive, the outcome view is kept up to date without noticeable delay. All model and parameter choices made in an interactive GUI session can be stored in XML and can be reloaded in another GUI session. They can also be stored as a Python script, which can then be run from the command line, independently of the GUI. This helps users who reach the limits of GUI functionality to get started with using BornAgain from Python, since it is much easier to edit a given script than to write one from scratch.
Until release 20.0, there was no mechanism to ensure backward compatibity. BornAgain 20 is not able to read GUI project files from older software versions.