I don't think an atantwo is needed. I *thought* I had read somewhere
that atan( y, x ) was equivalent to calling atan2 in Lua. Ensuring
there's no breakage when x == y would be nice, though. It was a little
surprising to see angle return degrees rather than radians, but it
does simplify my code:
dc := vbc - vac;
dr := vbr - var;
vi := 0;
if not( dc == dr ):
vi := round( angle( dc, dr ) / 60 );
fi;
% Compute the direction towards the first segment (to vertex of an edge).
vangle := vi * 60 * pi / 180;
Even simpler would be:
dc := vbc - vac;
dr := vbr - var;
vi := round( angle( dc, dr ) / 60 ); % returns 0 when dc == dr
% Compute the direction towards the first segment (to vertex of an edge).
vangle := vi * 60 * pi / 180;
Or accepting a third argument as the return value in the special case:
vi := round( angle( dc, dr, 0 ) / 60 ); % returns 0 when dc == dr
Cheers!
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