Subject: Re: Antialiasing
From: Mark Thompson <[email-masked]>
To: [email-masked]
Cc: [email-masked]
Date: Wed, 14 Sep 94 11:05:09 EDT

Ernie Wright <[email-masked]> writes:
> Think of the Adaptive Sampling settings as a way to control HOW MUCH
> antialiasing LightWave does.

Actually, I think its more clear to think of the Adaptive Sampling settings
as a way to control HOW MANY PIXELS (or how much of the image) get antialiased.

> Turning Adaptive Sampling OFF is almost the same as
> leaving it ON and setting the Threshold to 0.

However, I think its important to understand that they are NOT the same.
With adaptive on, you only have 1x spatial sampling until an edge is detected.
Then it uses 5x, 9x, or 17x depending on your AA setting. But even with the
adaptive threshold set to 0, it can miss edges because of the 1x sample for
edge detect. What this means is, if you have a very fine pattern in your image,
using adative (regardless of the threshold value) can cause "dropouts"  or
breaks in the pattern. With adaptive off, those dropouts are 5 to 17 times
less likely to occur (depending on AA). BTW, both motion blur and depth of
field disable adaptive edge detection.
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