"Robert McGregor" <rob### [at] mcgregorfineartcom> wrote:
> "Kenneth" <kdw### [at] gmailcom> wrote:

> > This is the 2nd part of my task. I looked up 'gaussian blur', and I see that it
> > involves matrix use in some way. I'm still a rank beginner when it comes to
> > manipulating matrices, but aside from that small problem (ha), I can't even get
> > a *basic* experiment with a matrix to work in v3.8xx for Windows
>
> Okay, I didn't use a matrix in that sense, i.e., the matrix keyword as used for
> transformations. I just built my own Gaussian smoothing matrix using a 2d array,
> like this (note the symmetry):
>
> #declare ConvolutionKernel = array[5][5] {   // Smoothing matrix
>    {1,  4,  7,  4, 1},
>    {4, 16, 26, 16, 4},
>    {7, 26, 41, 26, 7},
>    {4, 16, 26, 16, 4},
>    {1,  4,  7,  4, 1}
> }

Yes, it's a mathematical "matrix" - but with what we're doing with it, it's
implemented as an _array_ in code.   Not many working parts under the hood for
doing matrix math at the moment.

So I guess "array processing algorithm" would most clearly describe the
operation.

I did similar here:

http://news.povray.org/povray.binaries.images/thread/%3Cweb.5e9e3e93521c7ab7fb0b41570%40news.povray.org%3E/?ttop=432310
&toff=50

And probably for the Fast Fourier Transform and other places where I needed the
matrix structure to accomplish what I wanted.

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