Cousin Ricky <ric### [at] yahoocom> wrote:
> On 10/02/2016 03:57 PM, Mike Horvath wrote:
> > How do you evenly space points within a circle? Using a spiral? Or maybe
> > a hexagonal/triangular grid? I'm not sure it's possible.
>
> Based on my jittered circular renders, just having the points in each
> ring evenly spaced would be quite sufficient.
>
> But taking a closer look at how the points are spaced, I believe I know
> how they computed those positions.  (I'd verify my guess by looking at
> the code, but if I still had the mental stamina to do that, I'd be
> *writing* POV-Ray.)  A wild guess at why they chose to do it that way
> would be to facilitate adaptive sampling.

I was going to guess what it might NOT be... perhaps not something to do with
degrees around each circle...?

Have you tried unequal numbers yet? I did and here's the result from 4 X 6.
You'll see it doesn't spread around evenly at all.
The formula or equation used would be interesting to know. I searched the 'net
for equations showing pictures of concentric circle points and nothing like this
found, plenty of evenly spaced points though. Maybe its peculiar to area_light
but sure would be interesting if it isn't a commonly known math equation and a
complex formula instead.

I was into those source files a long time ago, playing with tiny bits and
recompiling. Nothing ever achieved really by doing so. I just liked to see what
was going on with it more than anything.

Bob

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