When using the samples, the interpolated points get abrupt steps because the system cannot receive all events in a short period of time.
This is more noticeable when the samples are set to 10 and the pen is moved very fast. The problem with post-processing smooth is that is applied to all stroke and this removes details.
The smart smooth is automatic and detect only the segments in the stroke where the system was unable to capture all movements and apply a smooth algorithm.
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