[Insight-users] Help using the processObject::update() method works

[tjswift at telus.net]

Hello Everyone,

    I've spent the better part of today examining the code for the 
DeformableMesh3DFilter and the UnaryFunctorImageFilter. My current guess is 
that DeformableMesh3DFilter::advance() and 
UnaryFUnctorImageFilter::ThreadedGenerateData() are the two respective 
functions that cause the bulk of the deforming/Image processing to take place. 
Specifically in UnaryFunctorImageFilter::ThreadedGenerateData():

"while( !inputIt.IsAtEnd() ) 
    {
    outputIt.Set( m_Functor( inputIt.Get() ) );
    ++inputIt;
    ++outputIt;
    progress.CompletedPixel();  // potential exception thrown here
    }"

However, I can't seem to figure out for the life of me how those two methods 
ever get ran. Consequently, I can't write my own filter/Deformable Model 
because I don't understand how to specify which methods will be ran when update
() is called.

I apologize if there is some document on "developing filters for itk" that I 
should be reading, but any help would be greatly appreciated.

Thank's for your time.

-Chris