[Paraview] Volume Rendering with opacity mapping and specular highlights

[Aashish Chaudhary]

Matthew,

* Can you send us the exact number you are putting in for the transfer
function? Make sure that you have values for the entire range of scalar
values?

* Are you using OpenGL2 version?

- Aashish

On Wed, Sep 23, 2015 at 1:18 PM, Mathew Guilfoyle <mrguilfoyle at gmail.com>
wrote:

> Thanks for the suggestions.  After looking into it further the type of
> visualisation I am after is volume rendering of the data with an opacity
> transfer function based on the scalar data values.
>
> I have set up my volume rendering to have full (i.e =1) opacity through
> the range of scalar values I’m interested in, reducing to near transparency
> either side of this.  I also want specular highlighting of the opaque
> tissues.
>
> However, despite these settings Paraview does not seem to render any
> voxels as fully opaque and there is certainly no specular highlighting.  Is
> this a known limitation?
>
> Many thanks
>
> On 21 Sep 2015, at 15:10, David E DeMarle <dave.demarle at kitware.com>
> wrote:
>
> Two suggestions:
> * try contour filter instead of threshold if contour isn't available,
> apply cell to point first.
> * try the clip filter with the clip type set to scalar.
> hth
>
> David E DeMarle
> Kitware, Inc.
> R&D Engineer
> 21 Corporate Drive
> Clifton Park, NY 12065-8662
> Phone: 518-881-4909
>
> On Mon, Sep 21, 2015 at 9:40 AM, Mathew Guilfoyle <mrguilfoyle at gmail.com>
> wrote:
>
>> I would be grateful for some advice on volume and surface rendering in
>> Paraview.
>>
>> I am trying to generate 3D skull models from CT data.  The reason for
>> using Paraview is to take advantage of the detailed fly-through/movie
>> capability.  I can generate an acceptable 3D model that I can interact with
>> in OsiriX and 3D Slicer, both of which I believe use VTK.  However, in
>> Paraview I am struggling to create a 3D model that looks any good.
>>
>> When I apply a threshold filter and view as a ‘Surface’ the image is a
>> lot more ‘blocky’ than in the other two applications.  The image is
>> dominated by the artifactual lines due to the original data being acquired
>> as axial slices; whereas in OsiriX and 3D Slicer this gets smoothed out and
>> the ‘genuine’ surface skull features (sutures etc) stand out.
>>
>> I realise this is probably question of apply the correct series of
>> filters and that the other two apps do this ‘under the hood’.  However, i
>> have tried to apply Decimation and Smooth to the extracted surface and am
>> not making any headway.
>>
>> Any pointers would be very welcome
>>
>> M
>> _______________________________________________
>> 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 ParaView Wiki at:
>> http://paraview.org/Wiki/ParaView
>>
>> Search the list archives at: http://markmail.org/search/?q=ParaView
>>
>> Follow this link to subscribe/unsubscribe:
>> http://public.kitware.com/mailman/listinfo/paraview
>>
>
>
>
> _______________________________________________
> 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 ParaView Wiki at:
> http://paraview.org/Wiki/ParaView
>
> Search the list archives at: http://markmail.org/search/?q=ParaView
>
> Follow this link to subscribe/unsubscribe:
> http://public.kitware.com/mailman/listinfo/paraview
>
>


-- 



*| Aashish Chaudhary | Technical Leader         | Kitware Inc.            *
*| http://www.kitware.com/company/team/chaudhary.html
<http://www.kitware.com/company/team/chaudhary.html>*
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/paraview/attachments/20150923/3504e979/attachment.html>