Chercher l'erreur ConvexHull

Noel Lambert shared this problem 5 months ago
Solved

Pourquoi dans le fichier attaché ConvexHull({A,B,C,D}) retourne un polygone erroné ?

Comments (12)

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newly an update problem

move A

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exact, bien attrapé


et pourtant j'avais "secoué" la figure de R-W

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strange

open the file

move B


then move D around AC (note convexhull when A C D are aligned)

then move C

I think there is a bug when the points was created in aligned positions

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an update problem mean this is normal ?

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Depending on which person has the problem :wink:

(yes, sometime has update problems in GGB (for example Locus() )

then you can make a bug-report and/or a workaround)

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When I look to this bug as black-box, then I see the following statements (in the attachment)

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Workaround (with small difference between A and the corner of Convex-Hull)

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if you zoom with the mouse then the problem disappear

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Thanks, yes I see this (now) too.

Spekulation:

Moving A with the mouse follows a pixel unit.

This unit changes with the zoom.

This means that A can no longer be manually set to f with sufficient accuracy (?).

In this version this can be done with a new button.

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Another question is: what is the possible path or area of C.

But I think for the developer the hints in this version are good enough and far more than usual.

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Thanks, we've add a new algorithm for v525 which should work better

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v525 online

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Thanks, Its works!

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