[vtk-developers] vtkProcrustesAlignmentFilter

[John Biddiscombe]

I can only speak for myself here....

The main reason I needed a datasetcollection that supported updates was for
a vtkDXFReader class, which outputs 2 collections, one for layers in the DXF
file and one for Blocks. DXFReader descends from ProcessObject and simply
exposes two outputs which operate normally

Then I wanted to take a series of test points (probe points) and compute the
field strength at the points from a transmitter and using a high resolution
building database as the "scenery".
Later on - multiple "Test points" sets were generated and the field strength
computed for each and a collection of field strengths ouput.
(There are lots of permutaions involving different scenery files or
different test points, or different transmitter locations/frequencies etc
etc)

I do not want to do anything at all to the existing update mechanism or
modify any of the existing filters. This is important. No messing with
existing streaming.

BUT...
If one decides to develop a custom filter which is capable of iterating over
lists of inputs, the existing streaming mechanism supports
Pieces of type : ImageData Extents
Pieces of type : Polydata piece number (or cell ID a to b)
all one needs to do is add
Pieces of type : Collection index start and end (List ID a to b)

This would only be used when the developer specifically chooses to support
lists as inputs and there is no need to modify the many hundreds of existing
classes. I only mentioned it in the hope someone else would do it :). (I
haven't really got deeply involved with multiple CPUs - yet)

ttfn

JB