|
 |
In the second last paragraph it reads:
Although the preliminary passes render only as many pixels as needed,
the 1*1 pass re-renders every pixel so that anti-aliasing and file
output
streams work properly. This makes the scene take up to 25% longer
than
the regular 1*1 pass to render, ...
If the text correctly describes the behaviour, then the figure of 25%
should
be corrected to 33%. with +SP65536 (or some other power of 2 that
exceeds
the image size), the following number of pixels will be rendered:
size pixels for the final frame
size/4 pixels for the 2x2 preview
size/16 pixels for the 4x4 preview
size/64 pixels for the 8x8 preview
...
In total that converges to
\sum_{n>=0}1/(4^n) = 4/3,
which is 33% more than the output number of pixels.
Mark Weyer
Post a reply to this message
|
|
