space_cadet wrote:
  > As for 'sane' numbers, I'm using real world numbers to model real world
> values...
Those would go from astronomicals to subatomics...


-- 
 From a certain point onward there is no longer any turning back.
That is the point that must be reached.
Franz Kafka

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space_cadet wrote:
> I'm juggling my time between work arounds to meet some deadlines and trying
> to get to the bottom of this.  I'll have to look into it deeper as time
> permits, so I havent been able to explore all the helpful suggestions here
> yet.
> 
> But one thing I'm seeing today is curious. I isolated one very small piece
> of geomtery. Rendered it in native scaling, and it rendered in one second.
> I scaled it by the .0000254 and it took 10 seconds to render (and I did
> adjust the camera position so that the geometry covered the exact same
> image portion.) I then scaled it to .254 and it rendered in 3 seconds.  The
> slow down is porportional to the degree of scale, not just the scale itself.
> Does that make ANY sense at all?
> 
> On a similar note, a light source I have was positioned at <-9500, 0, -9500>
> and rendered fine.  But when moved to <-95000, 0 , -95000> * 3600, the
> render hung, and I had to kill it.  Again, slowdown proportional to the
> precision/magnitude of the values involved in the computation.
> 
> All this has been done on 32 bit architectures so far (linux and windows).
> As of yesterday, I did a custom build on a 64-bit mega cluster. I've only
> rendered my 'workarounds' on there so I havent learned anything yet, but
> will shortly be playing with these issues in 64 bits to see if that sheds
> any light.
> 
> I've just never seen this sort of thing before.

Does the same problem occur with the 3.7 beta?

If so please post a small sample that demonstrates the problem and I will
investigate.

-- Chris

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Hugo <hug### [at] yahoocombr> wrote:
> space_cadet wrote:
>   > As for 'sane' numbers, I'm using real world numbers to model real world
> > values...
> Those would go from astronomicals to subatomics...

LOL, yes indeed.  However, my numbers werent that extreme.  I knew they were
aggressive, so I tried them with my fingers crossed, and they worked fine.
(until this problem surfaced much much later).

Actually, on first attempt, I scaled the spacecraft into kilometers (from
native milimeters) and positioned it at orbit altitude (in km).  Here is
where I saw many polygons disappearing from the spacecraft geometery,
although render speed was fine. So I reconfigured my scene such that the
craft stayed at the origin, and translated the earth away to the
appropriate distance, keeping all scales.  All was right with the world
from then on. (...until now)

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Chris Cason <del### [at] deletethistoopovrayorg> wrote:
> >
> Does the same problem occur with the 3.7 beta?
>
> If so please post a small sample that demonstrates the problem and I will
> investigate.
>
> -- Chris

Ah, I wont have time to explore a whole new code base for some time yet. I'm
really very pressed with deadlines at the moment (I'm making do with usable
workarounds).  As time permits me to investigate more exhaustively, I'll
put this on the list and let you know.

Thanks for the suggestion.

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