The 2 images here are from Bryce and POV, featuring a mesh and the
application of what POV calls radiosity and what Bryce calls true ambience.
I think in both cases the "radio-ambience" part of this experiment is lost.
The effect in both is too subtle. I shall prolly come back to this feature
in my next comparison. One thing is for sure tho, decent true-embience in
Bryce takes an age to render (114-ray option used in this experiment),
whereas POV does not struggle unduly when the default radiosity options are
inserted.
Mesh-wise, I think POV wins. The artifacts are not so evident. One slightly
pecular thing I found was having to rotate the whole head through 180*y
before the final Brycian transpositions were applied. My test camera was way
off compared with the final location as dictated by the Bryce camera.
Positioning, rotating and scaling the mesh was not entirely successful as
you can see by the differences. OBJuvPOV seemed to be reporting odd min max
info for the POVed OBJ head file; because the translation-to-centre aspect
of the job was producing a mesh that was "resting" on an axis instead of
being plum-centre. After much tinkering around with spreadsheets etc. I
decided to use mins and maxs derived from the vertice [1] information in the
head inc file - writing that down has just made me realise that I forgot to
take into account the hair y-extent too, which explains why I had to fudge
the y-pos of the camera from its true Bryce location. However, that still
does not explain the axis-resting part of the problem.
Placing the Sun in POV was tricky, until I realised that the information
that Bryce was reporting on Sun location was prolly pointless because per
default, the Sun is linked to the camera - and in POV that's where I ended
up putting the parallel Sun light. The shadows all seem to match except the
yellow sphere's - in POV it's visible on the neck of the mesh. The light of
the POV sun was White*2.
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[1] To be really accurate would prolly have required taking the normals into
account but that way madness lay.
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Download 'POV_mesh_radiosity.jpg' (83 KB)
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Preview of image 'POV_mesh_radiosity.jpg'
![POV_mesh_radiosity.jpg](/povray.binaries.images/attachment/%3C3d694cb2%40news.povray.org%3E/POV_mesh_radiosity.jpg?preview=1)
Preview of image 'Bryce_mesh_true_ambience.jpg'
![Bryce_mesh_true_ambience.jpg](/povray.binaries.images/attachment/%3C3d694cb2%40news.povray.org%3E/Bryce_mesh_true_ambience.jpg?preview=1)
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