POV-Ray : Newsgroups : povray.binaries.images : Noise3d and Megapov 0.5 : Re: Noise3d and Megapov 0.5 Server Time
2 Oct 2024 02:18:15 EDT (-0400)
  Re: Noise3d and Megapov 0.5  
From: Jerome
Date: 23 Jun 2000 10:23:26
Message: <395372DB.DDDFB826@iname.com>
Warp wrote:
> 
> Lots of interesting stuff
>
	You're right, that's what I meant when I said that the
statistical distribution is heavily distorted. On the other
hand, does it matter so much since it is basically a random
function anyway? My correction ensures that the function
gets changed as little as possible (in value as well as in
slope) which has two advantages in my eyes:
* it's easier to use for those who are used to the old one
(and it doesn't change anything for the others);
* it gives more variation than Nathan's fix (ok, you can get
as much variation by using a color_map where it is possible,
but what about the way it changes other functions such as
ridged multifractal for example?)

	So I guess, my question is: both changes (mine and
Nathan's) have advantages and drawbacks, which would you
prefer to see included in pov? Or would you like to see both
with an option? (that would also allow to keep the old
noise3d) knowing that I think this option would have to
affect the whole scene...

		Jerome
PS: 
> Your fix (as far as I can deduce from the images) would be to keep the
> wrong amplitude of the sine curve, but when it approaches 1 it's multiplied
> with a correcting factor that lowers the highest parts of the curve so that
> it fits under the amplitude of 1.
	You're basically right. I'd just like to add that the
change is continuous (so you won't see a line in your pic
with the old moise3d on one side and a scaled version on the
other).

-- 

* Doctor Jekyll had something * mailto:ber### [at] inamecom
* to Hyde...                  * http://www.enst.fr/~jberger
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