Re: bad bezier behavior

From: [at]} <Gérard>
Date: Mon, 20 Dec 2004 18:11:37 +0100

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Fyodor,

> Could anyone explain the fact that a segment of a Bezier curve is
sometimes incorrectly drawn as a straight
> line?
> The picture is attached: it also visualizes the array of 10 Ports.point's
which was passed to the
> Views.Frame.DrawPath procedure.
>
> The second picture shows that the Bezier segment for the anomalous four
points is well-defined (the middle
> red curve segment was produces in an independent drawing application
using the four points).
>
> The effect is stable with respect to sufficiently small deformations of
the View's parameters -- but
> disappears for larger deformations, and reappears (with another segment
drawn incorrectly) for another set
> of parameters.
>
> Perhaps there is a way to detect and prevent this condition beforehand?

Code you give some code or values? I tried quickly to reproduce your
pictures with Brahe (http://www.zinnamturm.de/#Brahe), but I get no error.

Cheers.
Gérard

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Received on Mon Dec 20 2004 - 18:11:37 UTC

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