query about beamChain.

Greetings,

Apologies for the elementary question about PolyRound. Sometimes when I call beamChain I get warnings "Tan() parameter could not be converted...".

Typically, either a portion of the curve is not rendered (the first vertex or last), or sometimes the entire curve is not rendered.

Is there some guidance on how do avoid these sorts of problems?

Here is a sample codeblock that causes such a problem:

R = 1.6;
PTL = [ [20,0,R], [19,2,R], [12,2,R], [10,4,R], [1,4,R], [0,3,R], [0,0,R] ];

polygon(polyRound(beamChain(PTL, offset1=0.4, offset2=0, mode=1), 20));

As a side-note, if I call it without "mode=1", OpenSCAD does not render anything.

I'm running OpenSCAD 2019.05, in case this is relevant.

Your sample code works fine, so I imagine the problem must be in the geometry I'm submitting to beamChain.

edit: after a little fiddling around it seems the last coordinate [0,0,R] is the one causing the trouble. If I change it to [0.1,0,R] the code runs as I would expect. Perhaps the code can't handle points at the origin?