On 10/12/2010 20:15, Thorsten Froehlich wrote:
> On 10.12.10 19:20, clipka wrote:
>>> Except that spheres do not get bounding boxes.
>>
>> But I guess they are included in the bounding box tree, so they'd
>> normally
>> be bounded hierarchically if I understand the bounding mechanism
>> correctly,
>> right?
>
> IIRC yes.
>
> Thorsten

Excepted that in source/backend/parser/parse.cpp, the volume of each 
bounding box is compared to INFINITE_VOLUME (aka BOUND_HUGE, i.e. 2.0e+10).
(even if sphere does not use bounding box for pruning intersections' 
computation, it got a bounding box which is use for the volume)


as infinite in parse.cpp, not entering the bounding tree.

I would ponder the usage of BOUNDS_HUGE as a criteria against a volume.

than (or equal) BOUNDS_HUGE) should still be infinite.

What about comparing each dimension of the bounding box instead ?
(if it's bigger in at least one dimension, it's infinite, otherwise it 
stay finite)

volume computation has issue with very large & very thin bounding box: a 
larger thin object might be more finite than a smaller but thicker one 
(who could be tagged if infinite).

E.g: bbox of size <1e+7, 1e+7,1e-4> is finite.
      bbox of size <1e+6, 1e+6, 1> is infinite.


Your thought ?

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