William F Pokorny <ano### [at] anonymousorg> wrote:

> Got up to go to the bathroom(*) and, wow, a lot of posts in this thread.

> Lastly, you could play with higher adc_bailout values too as a solution
> to the v3.7 rendering.

I thought this was just straight rendering - no radiosity.

Also, I replaced all of the ambient statements with emission.

> On your particular question about artifacts. The discs at larger radius
> values will start to cross each other. Where they do there will be a
> seam of numerical instability somewhat like coincident surfaces. Some
> likelihood this is the cause of the artefacts, but unsure how to be sure
> at moment. Can you filter out some range of discs closer to the camera
> location?

I would think the lines would be curved in that instance?

Just out of curiosity, I was wondering what the actual overall scene looked
like, so once I wrapped my head around the coordinate system and
camera-to-look_at orientation, I was able to pull the camera back and look down
over the entire undistorted market.
(see attached)

There are places where there are significant holes / spaces.
I'm wondering if perhaps part of the problem may be that the lines are places
where the rays are making it through to the black background.

Perhaps a non-zero (1/255) sky_sphere or background may help, or something like
a fog effect where the foreground is crystal clear, but the far-away spaces get
filled in with a lighter color.  Maybe some sort of large box with a gradient
that's the 4th root of the normalized total distance... that sort of thing.

Due to the time difference, I'm _just_ getting up and having First Coffee - so,
you're getting what you're paying for.  ;)

- BW

A huge point set like this is a real treat to play with, since it is large,
asymmetric, offers human-recognizable structure, and has color data built in.
I've been wanting to do a 3D convex hull algorithm, and this would be a great
final test for that.
Wondering what would happen if instead of discs or cylinders or spheres, _cones_
were used instead, oriented looking straight at the smaller face and the larger
end being just large enough to protrude: maybe that might fix the dark artifact
lines if it's a see-through effect.

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