Stephane Marty <alb### [at] wanadoofr> wrote:
: Well, what is clear to me is that your opinion is a bit influenced by
: something I don't understand.
: Too bad.

  I don't think it should be so hard to understand.

  - Your patch certainly makes the so-called "color bleeding" more evident.
This, however, doesn't make the image look better or more realistic, only
kind of overexposed.

  - As seen in the two example images made with my scene, the brightness seems
to need some fixing. At least to me the megapov version looks more like it
should be (I'm talking about the white wall). If you look at the image created
with your patch and compare the brightness of the colored walls to the white
wall, there seems to be an odd discontinuity: The colored walls are well lit
while the white wall is quite dark. In the real word the light reflecting
from the side walls, the floor, the backwall and even the objects should make
the white wall more lit.

  - Your patch seems to have some graininess problem which is somewhat evident
in the example image in the www-page of the patch. If I understood correctly,
it happens when the sample count is too low. In megapov even an extremely
low sample count creates almost perfectly smooth illumination. It was mentioned
that your patch may need even 10 times more samples than megapov needs to
create a non-grainy image (80 samples vs. 800 samples).

  - Your patch is very slow compared to megapov. Even when megapov uses
recursion level 4 and your patch uses only recursion level 2 (which of
course reduces the quality), your patch took twice the render time of
megapov to get an image of approximately the same quality. Even then some
blotchy spots can be seen in some parts of the scene (probably due to the
low sample count?).
  Somehow I also have the feeling that using antialiasing would have made the
render time even longer compared to megapov (I may be wrong here, of course).

  - You haven't rendered the sample image at a higher resolution (eg. 640x480)
and somehow I have the feeling that using the same radiosity settings but
using higher resolution might cause graininess in the image (of course it's
only a hypotesis). Please correct me if I'm wrong.
  The radiosity in megapov is independent of the image size. You can render
that image at any resolution you want and you will probably not get any
graininess, blotchiness or whatever that doesn't appear in the small image.
  If I'm correct in my assumption then I think that you'll have to increase
the sample count for bigger resolutions thus making the rendering times
extremely long.
  (If I'm mistaken here, please forgive me.)

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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