Superquadric attributes exact definition

ParaView Support
#1

Hi,

I’m using the Python interface of Paraview and the Superquadric() function, being quite familiar with background equations for superquadrics [*].

However, I could not find (in ParaViewGuide-5.7.0 for instance) the exact definition of these attributes, with respect to these background equations and Paraview (x,y,z) axes. For instance:

  • What is the exact definition of spherical angles theta and phi used here ? (for attributes Phi/ThetaResolution/Roundness)

That is, which one is in [0;pi], and with respect to z-axis ?

  • What is the exact definition, with respect to half lengths along each axis, of the Scale attribute ?

My tests tell me Scale[1] (denoting Scale[0] the first value of this list…) corresponds eg to z-axis in Paraview window. Whereas I was expecting it to be along the z-axis.

Thank you very much,

[*] eg pdf p. 5, top right, of https://authors.library.caltech.edu/9756/1/BARieeecga81.pdf

#2

https://gitlab.kitware.com/vtk/vtk/blob/master/Filters/Sources/vtkSuperquadricSource.cxx

Based on "Rigid physically based superquadrics", A. H. Barr,
   in "Graphics Gems III", David Kirk, ed., Academic Press, 1992.
#3

Thank you !

It seems to me AxisOfSymmetry is not accessible from Python (not an attribute of paraview.simple.Superquadric). Christmas being close, let me say I would appreciate it to be on some WishList. :wink:

Thanks again

#4

Here you go :slight_smile:

1 Like
#5

Christmas is already here ! Thanks again