POV-Ray : Newsgroups : povray.documentation.inbuilt : Anti-aliasing mode 3 : Re: Anti-aliasing mode 3 Server Time
7 Dec 2021 13:58:41 EST (-0500)
  Re: Anti-aliasing mode 3  
From: Jim Holsenback
Date: 23 Sep 2018 07:36:12
Message: <5ba77aac@news.povray.org>
On 9/22/18 7:39 PM, clipka wrote:
> Am 23.09.2018 um 00:26 schrieb Jim Holsenback:
> 
>> please review:
>>
>> http://wiki.povray.org/content/Reference:Tracing_Options#Anti-Aliasing_Options
> 
> My thoughts on it:
> 
> 
> Stochastic Seed:
> 
> - Typo: "Set's a value" should read "Sets a value".

oops

> 
> Sampling Methods Synopsis:
> 
> - Excellent! Love this mini section!

at least it's better than the run-on sentence that used to be there

> 
> Details, Type 1:
> 
> - The section states that "the adaptive non-recursive method is the
> default". I would suggest adding "if anti-aliasing is enabled" or
> something along those lines, because the "out of the box" default is no
> anti-aliasing at all.

yep

> 
> - It may or may not be worth also considering an optional alpha channel
> in the formula given (but see further below).

if you /really/ think it's worth it help me out a bit...i /did/ do 
something near the end of common as there was already a +ag discussion 
going on... it seemed to fit.

> 
> Details, Type 3:
> 
> - The formula for the actual maximum number of rays per pixel is
> literally written as "4^n" (four-caret-n), rather than using proper
> superscript notation. Not sure if this is an oversight or technical
> necessity. In the latter case, maybe Unicode character U+207F would be
> an alternative to genuine superscript.

the hex equivalent was too small... 4<sup>n</sup> looked slightly better.

> 
> - The word "moire" in "moire pattern" lacks an accent.

found the hex version used elsewhere on the page

> 
> Common section:
> 
> - The common section ("With all methods..."), as currently written,
> implies that the `Jitter` setting affects all anti-aliasing modes; that
> is incorrect: Anti-aliasing mode 3 always uses a constant amount of
> jitter. I would suggest to use something like the following wording instead:
> 
> ----------------------------------------------------------
> Another way to reduce anti-aliasing artifacts is to introduce noise into
> the sampling process. This is called jittering and works because the
> human visual system is much more forgiving to noise than it is to
> regular patterns, and is inherent in anti-aliasing mode 3. When using
> one of the other methods, the location of the super-samples is also
> jittered or wiggled a tiny amount jittering by default, but may be
> turned off with the Jitter=off option or -J option, or the amount of
> jittering can be set with the Jitter_Amount=n.n option. When using
> switches the jitter scale may be specified after the +Jn.n option. For
> example +J0.5 uses half the normal jitter. The default amount of 1.0 is
> the maximum jitter which will insure that all super-samples remain
> inside the original pixel.
> -----------------------------------------------------------

i mangled this paragraph on purpose because i was fishing for 
clarification... lol and you bit!

> 
> Additional noteworthy information:
> 
> - It may be worth noting that if the image contains an alpha channel,
> that channel will also be considered in the comparisons, pretty much
> like the colour channels, except that unlike the other channels it is
> not subject to `Antialias_Gamma`.

almost verbatim near the end...

> 
> 
>> besides the am3 additions i also did some general cleanup and added a
>> few visual cues to help better separate the method detail descriptions
> 
> Would it make sense to use sub-headings instead of just bold text?

ugh...i'm being lazy

> 
> Also, I guess it might be useful to add another visual cue between the
> type 3 description and the subsequent description of common features.

wasn't /feeling/ any of the several things i tried so i left it as is


Post a reply to this message

Copyright 2003-2021 Persistence of Vision Raytracer Pty. Ltd.