[Paraview] netCDF, Multiple outputs, multiple point data arrays

[Brad King]

John Biddiscombe wrote:
> I'm working on a netCDF reader which is working well on the majority of 
> datasets and will handle multiple point data arrays using the 
> PointDataArraySelection method that can be found in several of the more 
> advanced paraview readers. The Gui allows you to select which point data 
> to read. In this case, all the Variables present in the netCDF file are 
> basically the same size (identical x,y,z,t,spacing,origin etc)
> 
> But...
> I've got some netCDF datasets that have mutiple Variables present in 
> them - with different sizes. So that either of the above mentioned 
> variables may be of different sizes. What I'd like to do, is create N 
> outputs, each with possibly M point data arrays. Effectively, calling 
> SetNumberOfOutputPorts in the execute information and assiging the 
> relevent information to them.
> 
> Can the PointDataArraySelection method be extended to handle this case, 
> so that the user can configure reads from the paraview GUI? if so, can 
> anyone give me either an example or some clues as to what to modify. If 
> this case can't be handled, then it's not too serious and I'll just 
> output one (probably the largest) of the "sets" of data.

This isn't very easy because ParaView creates a whole bunch of internal 
objects according to the number of outputs the reader produces.  Once 
this is set it cannot be changed without removing the reader and 
creating a new one.  Therefore the set of outputs to read cannot be 
configured by the GUI.

Changing the number of output ports during execution is not a very 
new-pipeline thing to do.  There is currently multiblock (or composite) 
output support being developed, so you reader would produce one output 
that consists of several blocks.  Each block would correspond to one of 
what you are now calling outputs.

-Brad