  Interferometric scattering microscopy is a powerful technique that enables
various applications, such as mass photometry and particle tracking. Here we
present a numerical toolbox to simulate images obtained in interferometric
scattering, coherent bright-field, and dark-field microscopy. The scattered
fields are calculated using a boundary element method, facilitating the
simulation of arbitrary sample geometries and substrate layer structures. A
fully vectorial model is used for simulating the imaging setup. We demonstrate
excellent agreement between our simulations and experiments for different
shapes of scatterers and excitation angles. Notably, for angles near the
Brewster angle, we observe a contrast enhancement which may be beneficial for
nanosensing applications. The software is available as a Matlab toolbox.
