scott <sco### [at] scottcom> wrote:
> > The attached shows artifacts present at various accuracies for the function
> > sqrt(x*x+y*y+z*z)-1.>
>
> Assuming you've got no pattern displacement in any of those images, it
> looks to me like it's something to do with the shadow ray being started
> too close to the surface (and hence the tracer immediately thinks the
> shadow ray has been blocked by the isosurface itself).

I should have guessed that, since I ran into shadow ray problems last summer
with the raymarching stuff. The shadow ray's origin had to be spaced from the
initial hit point (by backing it up toward the camera or outward from the
surface), or else artifacts would appear.

Attached is the same scene, this time with no_shadow applied to the isosurfaces.
Making the light_source shadowless also works.

I vote for a new keyword addressing this issue! Not only are the artifacts ugly,
but I would imagine they also slow down render times when aa is used.

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