[vtkusers] Automatically change radius of sphere when a variable changes its value

[Ken Martin]

Position your spheres using the Actor's SetPosition, I am guessing you are
changing the spheres' centers in the SphereSource which is the issue.

On Mon, Aug 7, 2017 at 8:30 AM, M. Jordan <mjordan at live.at> wrote:

> Hello,
>
> i tried to use the ->SetScale() options but it turned out that this
> changes the position as well.
> My goal is to find the fastest way to change the radius of the spheres,
> without affecting their positions.
> Any idea how to solve this issue?
>
> Thank you very much!
>
>
> ------------------------------
> *Von:* Ken Martin <ken.martin at kitware.com>
> *Gesendet:* Freitag, 04. August 2017 16:28
> *An:* M. Jordan
> *Cc:* vtkusers at vtk.org
> *Betreff:* Re: [vtkusers] Automatically change radius of sphere when a
> variable changes its value
>
> 1) actor->SetScale(...) instead of changing the sphere source
>
> or
>
> 2) use a Glyph3DMapper with a scale array to control the scale of each
> sphere
>
> or
>
> 3) vtkOpenGLSphereMapper with a scale array
>
> Which solution works best depends on the specifics of your use case, ala
> is only one sphere changing radius?, are they all?, are they all changing
> by the same amount? one actor? 100 actors? etc.
>
>
>
>
>
>
> On Fri, Aug 4, 2017 at 10:00 AM, M. Jordan <mjordan at live.at> wrote:
>
>> Hello,
>>
>> I have a scene with many spheres (about 100) in my QVTK-Widget.
>> Now I would like to achieve that the radii of the spheres change
>> automatically when a variable changes its value.
>>
>> Right now I add the spheres to the scene, start a timer and in the timer
>> callback I change the radius of the SphereSources depending on the
>> variable. Finally, I call qvtkwidget->update(); to update the spheres in
>> my scene.
>>
>> It works, but i would like to improve the speed. Any ideas how to update
>> spheres faster? Is there any possibility to only "re-render" one sphere and
>> not the whole scene?
>>
>> Thank you!
>>
>>
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>
>
> --
> Ken Martin PhD
> Distinguished Engineer
> Kitware Inc.
> 28 Corporate Drive
> Clifton Park NY 12065
>
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-- 
Ken Martin PhD
Distinguished Engineer
Kitware Inc.
28 Corporate Drive
Clifton Park NY 12065

This communication, including all attachments, contains confidential and
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