[Ves] Modifying actors properties before rendering them

[Carlos]

Hi,

Regarding the first question about fixing the trihedron in the screen I will
try to suggestion but I ' afraid that setting the ReferenceFrame to Absolute
it will change also the orientation behavior.  that is something that the
trihedron must match to the scene, as it gives orientation information. 
The goal is to display geometric objects in the space and the trihedron
gives the orientation but is fixed in the screen , ie, the translation is
blocked. A similar feature can be found in CAD software.
At this point I forgot to ask about if there is in VES a similar flag to
SetUseBounds() in order to avoid use the bound of one specific actor to
calculate the bounds of the scene.
I will post the checkings with setReferenceFrame.


Regarding the possibility to add a image (jpg for example) to the background
I already checked vesBackground.h and I saw some functions that could work,
specially setimage, that accepts a vesImage object. But in vesImage.h the
best function I have found is setData(const void *data, unsigned int size).
At this point I'm block as I do not know how to read a jpg file and pass it
to this function. Does setdata accept an vtkImageData object or something
similar?

Regards,

Carlos



-----Mensaje original-----
De: Aashish Chaudhary [mailto:aashish.chaudhary at kitware.com] 
Enviado el: miércoles, 20 de marzo de 2013 22:44
Para: Carlos
CC: ves at public.kitware.com
Asunto: Re: [Ves] Modifying actors properties before rendering them

Hi Carlos,

On Wed, Mar 20, 2013 at 5:22 PM, Carlos <ves at calculoandamios.com> wrote:
> Hi,
>
>
>
> In VTK I have derived the vtkAxesActor class in order to fix the 
> trihedron in a fixed place on the screen. For this I have override the
> RenderOpaqueGeometry() method that is called for each actor when a
> renderer->render() is invoked and I modify the position of the Axes to
> display it in the desired position.

Have a look at the vesTransformInteface.h. Based on your description, I am
thinking that you can call setReferenceFrame on the actor and pass it
vesTransformInterface::Absolute option.

>
>
>
> I’m aware of the limitations of this class in VES as it has been 
> discussed in a previous thread but I would like to know if there is a 
> similar way to modify the position of one actor before rendering it 
> with the camera parameters already established. My problem is that I 
> do not fully understand the workflow generated after a 
> renderer->render() call. I have checked the VES code and there are 
> some other classes involved as vesVisitor that I do not understand.
>
>
>
> In VTK I also display an image background using a second camera not 
> related with the interactor but as I understand it is not possible to 
> use a second camera in VES. I’m thinking in using the first approach 
> and modify the image position before rendering it. Does it make sense?

You can grab the background object from the renderer then you can set an
image on it. Look at the vesRenderer.h and vesBackground.h headers.

Let me know if this helps.

>
>
>
> Regards,
>
>
>
> Carlos
>
>
>
>
> _______________________________________________
> Ves mailing list
> Ves at public.kitware.com
> http://public.kitware.com/cgi-bin/mailman/listinfo/ves
>



-- 
| Aashish Chaudhary
| R&D Engineer
| Kitware Inc.
| www.kitware.com