RES: [Paraview] Newbie: contributing with an implementation of theSplatting algorithm

Mon Jan 22 11:47:42 EST 2007

El dl 15 de 01 del 2007 a les 23:54 -0300, en/na Renato N. Elias va
escriure: 
> Hi Jordi,
> 
> First of all I should tell you that I know nothing about what you told in
> your post since I'm not a visualization guy. I'm just a CFD developer and a
> ^curious^ user of visualization tools. Therefore, forgive me if I'm only
> wasting your time -- my intention was good ;o)

First of all, thank you for your time ;) I took a lot of time to answer
because we were preparing a ParaView introduction workshop to high
school students (I've just sent a message to the list about it, that is
placed here [1]). So, sorry for the delay.

> Some time ago I posted a message asking for some technique to visualize SPH
> (Smoothed Particle Hydrodinamics) and DEM (Discrete Element Method) data. At
> that time I got some answers addressing the visualization of particle data
> within VTK ([1, 2]) using a splatting algorithm (take a look here
> http://www.vtk.org/doc/nightly/html/classvtkGaussianSplatter.html)

Certainly, this can be used when implementing the Splatting algorithm,
but it only represents the very last step of the algorithm.

> [1] http://public.kitware.com/pipermail/paraview/2006-February/002550.html
> 
> [2] http://public.kitware.com/pipermail/paraview/2006-February/002547.html 
> p.s.: Some guys from CSCS lab are working with particle data visualization
> (http://www.cscs.ch/a-display.php?id=170). Once again, I don't know if this
> software (Sparticles) uses something related to the splatting technique.

The example from CSCS seems to take a 'surface rendering' approach,
while the Splatting algorithm is used to perform 'direct volume
rendering' DVR [2]. In DVR, all the 'volume' is rendered considering
that is internally heterogeneous.

So, it seems that the vtkGaussianSplatter can be used to implement the
algorithm but no Splatting Algorithm implementation is available in VTK.

> Regards
> 
> Renato N. Elias

Thanks for your answer. I rest a little bit more to see if somebody else
answers.

Regards,

jor;)i

References:
[1] http://truja.lsi.upc.edu/movibio/soft/paraview/Workshop
[2] http://en.wikipedia.org/wiki/Volume_rendering

> 
> 
> -----Mensagem original-----
> De: paraview-bounces+rnelias=nacad.ufrj.br at paraview.org
> [mailto:paraview-bounces+rnelias=nacad.ufrj.br at paraview.org] Em nome de
> Jordi Campos i Miralles
> Enviada em: segunda-feira, 15 de janeiro de 2007 17:41
> Para: paraview at paraview.org
> Assunto: [Paraview] Newbie: contributing with an implementation of
> theSplatting algorithm
> 
> Hi all,
> 
> I'm a PhD student [0] at Universitat Politècnica de Catalunya [1] and
> Universitat de Barcelona [2], working on Volume Visualization at MoViBio
> research group [3].
> 
> The research group has its own software system Hipovis [4], but I am
> evaluating the possibility of using other software systems. Right now, I'm
> evaluating using ParaView/VTK to test current research approaches on
> Focus+Context Volume Visualization based on the Splatting algorithm [5].
> 
> As far as I know, VTK libraries does not offer the Volume Splatting
> algorithm [6] and there are no available examples of implementing it using
> VTK. However, I found references to works that use VTK to implement
> Splatting approaches [7], but no code is available.
> 
> 
> 
> Hence, I have the following questions::::::::::::::::
> 
> A- Is there any VTK's architectural reason why the splatting algorithm does
> not suit the VTK libraries? May be implementing the splatting algorithm
> inside the VTK's pipeline architecture will not provide enough performance
> to develop research activities, will it?
> 
> B- Although ParaView offers fast volume rendering (textures), precise v.r.
> (RayCast) and both qualities v.r. (using VolumePro hw), will it be worth if
> I work on adding the Splatting algorithm and Focus+Context features? (for me
> it is worth because it is the basis of my thesis but I would like to know if
> there are other people also interested in it).
> 
> C- If I want to be involved in VTK development to implement the Splatting
> algorithm, which steps do you recommend me? From you experience, how long
> does it take to a PhD student (with C++ and graphics knowledge) to get
> involved with the project and develop new code? (I know this is a generic
> question, but I need some estimation). I already bought the two books
> [8][9], reviewed the coding standards [10] and subscribed to the list.
> 
> D- If I want to be involved in ParaView development to use the Splatting
> algorithm and implement Focus+Context features, which steps do you recommend
> me?  From you experience, how long does it take to a PhD student (with C++
> and graphics knowledge) to get involved with the project and develop new
> code? (I know this is a generic question, but I need some estimation). I
> already ordered the book [11] and subscribed to the list.
> 
> E- Which are the good and bad points of ParaView/VTK versus VolumeShop [12]?
> It seems VolumeShop is not really open source (and we are looking an open
> source project to get involved), it is mainly used on MsWindows platforms
> (and we are interested in a multi-platform environment), and it does not
> provide parallel rendering.
> 
> F- Which are the good and bad points of ParaView/VTK versus VolView [13]?
> 
> 
> 
> 
> I would like to known your opinion about these questions and any other
> possible important factors you think I should pay attention.
> 
> 
> 
> Thank you very much in advance.
> 
> 
> jor;)i
> 
> 
> 
> PD: I already have sent a similar post to VTK's list, specifically about
> VTK's issues.
> 
> 
> References:
> [0] http://truja.lsi.upc.edu/movibio/Members/jordi
> [1] http://www.upc.es
> [2] http://www.ub.edu
> [3] http://truja.lsi.upc.edu/movibio
> [4] http://truja.lsi.upc.edu/movibio/ResearchLines/soft
> [5] Lee Westover: Interactive volume rendering, 1989 [6]
> http://public.kitware.com/pipermail/vtkusers/2001-January/055005.html
> [7] Zwicker, Pfister, Baar and Markus Gross: EWA volume splatting, 2001 [8]
> The Visualization Toolkit An Object-Oriented Approach To 3D Graphics [9] VTK
> User's Guide [10] http://www.vtk.org/Wiki/VTK_Coding_Standards
> [11] ParaView User's Guide
> [12] http://www.cg.tuwien.ac.at/volumeshop
> [13] http://www.volview.com
> 
> _______________________________________________
> ParaView mailing list
> ParaView at paraview.org
> http://www.paraview.org/mailman/listinfo/paraview
> 