Rune nous apporta ses lumieres en ce 10-01-2007 12:33:
> Rune wrote:
>> For objects that fill a reasonably high percentage of the bounding
>> box (such as a sphere) it wouldn't be a big problem unless you really
>> care about high accuracy. For other objects though, such as, say, a
>> cylinder from <-1,-1,-1> to <1,1,1> with radius 0.01, testing all
>> points (with some proximity) within the bounding box is extremely
>> inefficient. However, pre-testing with trace lines within the
>> bounding box parallel with one or more axes could be used to weed out
>> by far the most points beforehand, and this would only be O(n^2).
> 
> ...in most common cases that is. It won't work for, say, a sphere with a 
> slightly smaller sphere carved out of it.
> 
> Come to think of it, the tracing could be used iteratively to do the volume 
> calculation in the first place. This would work in all cases and would only 
> be O(n^2*m) where m represents the complexity of the object.
> 
> Rune
What about a complex shape with another complex shape carved out of it, making a 
strange, one opening, hole?

-- 
Alain
-------------------------------------------------
Age is a very high price to pay for maturity.

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