[metapost] turningnumber revisited

[Boguslaw Jackowski]

Hi,

> I'm not surprised because at (0,0)  (1,1) and (2,0) we don't have C1
> continuity (as Dan said).

A triangle also doesn't have C1 continuity and well-behaves. The problem 
are cusps.

> IN
> -->------------+
>               |
>               V
> OUT           |   -180°
> --<------------+
>
>
>
> OUT
> --<------------+
>               |
>               ^ +180°
> IN            |
> -->------------+

You've illustrated perfectly the reason, why cusps are "nasty".

Thanks -- cheers -- Jacko

-- 
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  Bogus\l{}aw Jackowski: B_Jackowski at GUST.ORG.PL
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  Hofstadter's Law: It always takes longer than you expect, even
                    when you take into account Hofstadter's Law.
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