jwh wrote:

> My suggestion is: allow for the use of 4-dimensional homogeneous vectors and
> matrices to be switched on if advantageous. I could imagine that the
> calculation overhead could be reduced if successive transformations could
> be easily simplified to just one either by the programmer or by POVray.

I'm not quite sure what you're trying to get at. Possibly you are
confused by the syntax of the "matrix" transform, which takes only
12 floats, as the remaining 4 values are assumed to be <0,0,0,1>,
and that the order of the entries in ASCII formatting leads to a
matrix which is actually transposed with respect to the usual
convention of having the translation in the last *column*.

With this in mind, the formular presented in 2.2.7.1.4 is really
just the common matrix multiplication. It probably wouldn't hurt
if the matrix keyword supported specifying a 4x4 matrix directly,
you never know when it might come in handy.

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