zRcube

Another possible explanation : the example picture could have been computed using the smp (multi-thread) or the "distributed" code. This code uses some arithmetics to distribute the pixels to render. It's not impossible that a small bug in this arithmetics causes a one-pixel shift somewhere (for example at the beginning of each line, ...) . Or maybe there's a real bug somewhere.

Btw, if it's visually good... :) Why bother ? :)

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Mandor