1. The POV image appears to have some radiosity artifacts. Any that appear
in the Bryce image (as graininess) will be due to the number of rays used
(114). Again, in POV, the default radiosity settings were plonked in.

2. POV has taken the background white into account and so the ground is
brighter. In Bryce the atmosphere is off and the Sun too.

3. When developing the POV scene, prior to adding the radiosity features,
the sphere's roundness was still in visible due to shadow. However, in
Bryce, once the ambience was whacked up, the shadow was lost.

4. POV relies on the diffuse element of a texture, whereas Bryce uses the
ambient element. One can specify in Bryce an ambient colour and an ambient
level. In POV, one merely specifies an ambient colour. However, I used
"ambient 1" in POV as it seemed to eliminate more of the self-shadow that
was not visible in Bryce.

Conclusion: The Bryce version looks more pleasing but I suspect that there's
a good reason they call it "true ambience" rather than radiosity. I should
imagine that with some knowledgeable tweeking in POV, those artifacts could
be got rid of.

PS. After creating these 2 images I decided to determine the most accurate
POV camera angle for emulating the Bryce camera. With only about a pixel's
difference the angle appears to be 48 degrees - how this relates to Bryce's
FOV of 60 degrees I don't know, but when viewing the Bryce camera from above
it does appear to be approx 45 degrees.


The Bryce camera viewing angle in POV appears to be 48 degrees. Bryce has a
default of

Post a reply to this message

Attachments:
Download 'POV_radiosity.jpg' (30 KB) Download 'Bryce_true_ambience.jpg' (42 KB)

Preview of image 'POV_radiosity.jpg'

Preview of image 'Bryce_true_ambience.jpg'