Welcome to Fractal Forums

Fractal Math, Chaos Theory & Research => Theory => Topic started by: pauldoo on June 07, 2010, 04:55:32 PM




Title: How is the "distance estimator" derived?
Post by: pauldoo on June 07, 2010, 04:55:32 PM
Hi,
For my work in progress renderer I am using the distance estimation expression of "0.5 * |w| * log(|w|) / |δw|" which I found at the following link:

http://www.subblue.com/blog/2009/12/13/mandelbulb

This seems to work great, but I am very confused as to how this expression was derived.  Does anyone have pointers for that?


Title: Re: How is the "distance estimator" derived?
Post by: David Makin on June 07, 2010, 10:04:11 PM
This seems to work great, but I am very confused as to how this expression was derived.  Does anyone have pointers for that?

Not surprised you're having trouble finding it (at least here anyway) - the post is buried in "the thread" here (wait for it to locate):

http://www.fractalforums.com/3d-fractal-generation/true-3d-mandlebrot-type-fractal/msg8505/#msg8505

You may like to check out a number of the follow-up posts.