The terminator artifact is one that can be seen at the limit of lighting for models of low-poly subdivision (it is more obvious in low-poly meshes although it can be seen on very detailed meshes when closing up). As far as we know, the majority of unbiased renderers suffers from this problem. In biased renderers, it is somewhat easier to fix the problem.

In Thea Render, we didn't want a solution that could alter/bias material appearance but instead we very carefully compensate for the energy loss due to the terminator artifact dark zones. Our solution produces smooth renders even for very low-poly models with the basic assumption that the subdivision is uniform (i.e. not abruptly changing).

We are actually very proud that we have this working out-of-the-box for all engines.

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