Re: improvement of index-calculation

> const x, y, z: integer

If you can pass them as a unique const vector structure (without having to fill a vector structure for that sole purpose) like

	const xyz : TIntegerVector

you may be able to help the compiler generate better code by reducing register pressure at the call point (and pass everything via registers).
Since what this routine does is rather simple, call overhead is probably not negligible.

Eric
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