[vtkusers] ​Re: Normal vector of the surface of ellipstic cylinder

[Andrew Maclean]

Hi all,
In order to introduce more triangles, I don't think that there is any need
to do multiple successive extrusions.
I would suggest using vtkLinearSubdivisionFilter to achieve what I think
you want.

Please see the attached modification of your code.

Note:
1) You need to pass extrude through vtkTriangleFilter then apply
vtkLinearSubdivisionFilter.
2) Experiment with changing numberOfSubdivisions in the attached code.

Regards
    Andrew


> ---------- Forwarded message ----------
> From:
> ​​
> Girish Lande <girish.lande at agiliad.com>
> To:
> ​​
> arwtyxouymz <arw.tyx-ouy_mz at ezweb.ne.jp>
> Cc: vtkusers at vtk.org
> Bcc:
> Date: Fri, 28 Jul 2017 10:00:44 +0530
> Subject: Re: [vtkusers] Normal vector of the surface of ellipstic cylinder
> I think you need to find a way to introduce more triangles in your
> polydata.
>
> One way I can think of is to create multiple successive extrusions instead
> of creating one single extrusion. And then append polydata of these
> multiple extrusions which will definitely have more points and triangles.
> (Please see attached image). Your current polydata is represented by fig.
> A. and what you need is polydata as per figure B.
> [image: Inline images 1]
>
> On 28 July 2017 at 09:19, arwtyxouymz <arw.tyx-ouy_mz at ezweb.ne.jp> wrote:
>
>> Thank you Girish Lande!
>>
>> Can I not get normals the side surface of about my extruded object?
>> Should i change the extrusion method to create elliptic cylinder if I want
>> to get the side surface normals?
>>
>> But I don't know other ways....
>>
>> please tell me!
>>
>>
>>
>> --
>> View this message in context: http://vtk.1045678.n5.nabble.c
>> om/Normal-vector-of-the-surface-of-ellipstic-cylinder-tp5744
>> 171p5744185.html
>> Sent from the VTK - Users mailing list archive at Nabble.com.
>> _______________________________________________
>> Powered by www.kitware.com
>>
>> Visit other Kitware open-source projects at
>> http://www.kitware.com/opensource/opensource.html
>>
>> Please keep messages on-topic and check the VTK FAQ at:
>> http://www.vtk.org/Wiki/VTK_FAQ
>>
>> Search the list archives at: http://markmail.org/search/?q=vtkusers
>>
>> Follow this link to subscribe/unsubscribe:
>> http://public.kitware.com/mailman/listinfo/vtkusers
>>
>
>
>
> --
> thanks & regards,
> Girish
>
>
-- 
___________________________________________
Andrew J. P. Maclean

___________________________________________
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/vtkusers/attachments/20170729/e5056c83/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: dense_triangles.png
Type: image/png
Size: 44020 bytes
Desc: not available
URL: <http://public.kitware.com/pipermail/vtkusers/attachments/20170729/e5056c83/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: normals_at_each_point_in_cylinder.cpp
Type: text/x-c++src
Size: 9920 bytes
Desc: not available
URL: <http://public.kitware.com/pipermail/vtkusers/attachments/20170729/e5056c83/attachment.cpp>