This bug (http://news.povray.org/3c23b26c@news.povray.org) is a simple 
scaling problem.

In the file bezier.cpp there are three cross products (VCross) and
after each one you check the squared length of the resulting vector 
against BEZIER_EPSILON (1.0e-10). 
But the result of a cross product (a = b x c) is a vector (a) whose 
length is the product of the length of the two vectors times the sine 
of the angle.

||a|| = ||b|| ||c|| sin(b^c).  

so scaling b and c, as the bug report author does, there is  a value
of the scaling factor, below which a condition like

||a||^2 > BEZIER_EPSILON

is no more satisfied. It suffices to transform the three conditions
to:

||a||^2 > BEZIER_EPSILON * ||b||^2 * ||c||^2

and the image produced is quite independent from the scale factor.

HTH Massimo

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