[Gmsh] Forcing all jacobians to be positive

[Carole-Anne Daunais]

It works well, thank you!

Christophe Geuzaine <cgeuzaine at uliege.be> a écrit :

>> On 31 May 2020, at 17:12, Carole-Anne Daunais  
>> <carole-anne.daunais at polymtl.ca> wrote:
>>
>> Thank you Christophe for this quick answer!
>> What do you mean by setting the size directly? Is there another way  
>> I can set all shapes to be hexs instead of tets? I looked it up in  
>> the Archives but couldn't find.
>>
>
> I didn't understand that you want all-hexes. Can you try the latest  
> dev snapshot with Mesh.HighOrderOptimize = 1 or 2, and  
> Mesh.ElementOrder = 1 ? The optimization will be applied before the  
> subdivision, which should improve things.
>
>
>> Thank you
>>
>> Christophe Geuzaine <cgeuzaine at uliege.be> a écrit :
>>
>>>> On 29 May 2020, at 20:48, Carole-Anne Daunais  
>>>> <carole-anne.daunais at polymtl.ca> wrote:
>>>>
>>>> Hi,
>>>> I am using GMSH 4.5.6 to generate a 3d mesh. I used the following  
>>>> 2 lines in the .geo file to ensure that no element would have a  
>>>> jac.<0.
>>>>
>>>> Mesh.ElementOrder = 2;
>>>> Mesh.HighOrderOptimize = 1;
>>>>
>>>> It unfortunately didn't work for me. The mesh is generated, but  
>>>> the software failed (froze). Is there another way I can force all  
>>>> jacobians to be positive when creating my mesh?
>>>>
>>>
>>> It works fine here. However you should remove  
>>> "Mesh.SubdivisionAlgorithm = 2;" (and set the sizes you want  
>>> directly), as this makes it harder for the optimizer.
>>>
>>> You can also use "Mesh.HighOrderOptimize = 2;", which will apply a  
>>> global elastic smoothing step before the brute-force optimization.
>>>
>>> Christophe
>>>
>>>
>>>
>>>
>>>> Thank you,
>>>>
>>>> Carole-Anne
>>>>
>>>>
>>>>
>>>>
>>>> <test2.geo>_______________________________________________
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>>>
>>> —
>>> Prof. Christophe Geuzaine
>>> University of Liege, Electrical Engineering and Computer Science
>>> http://www.montefiore.ulg.ac.be/~geuzaine
>>
>>
>>
>>
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>
> —
> Prof. Christophe Geuzaine
> University of Liege, Electrical Engineering and Computer Science
> http://www.montefiore.ulg.ac.be/~geuzaine