Gilles Tran wrote:
> 
> This one puzzles me...
> The code below shows 2 bunches of cones. One is called "slow", the other
> one "quick". Render the code to see why : render the "quick" ones first
> and then the "slow" ones.
> The only difference between the slow and quick ones is that the slow
> ones have a slightly larger base radius.
> POV says that the slow cones are infinite objects !!!!
> I came upon this problem when rendering a tree : for some mysterious
> reason, some trees took forever to render (not counting parsing time).
> The "slow" cones below were (painstakingly) extracted from a file
> containing 16000 cones.
> 
> Scaling the cones or moving the camera sometimes make the problem
> disappear, sometimes not.
> 
> Any idea about what's going wrong ?
> 
> Gilles

Perhaps the programs epsilon limit is causing rounding errors ?

  Your slow cones are only .000004 pov units different between the
radius at each end. Adding .000010 to the first radius in the cone
statement at least removes the infinte object problem but it still
renders slowly.

-- 
Ken Tyler
  
mailto://tylereng@pacbell.net
http://home.pacbell.net/tylereng/links.htm

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