On 19/06/2011 06:42 PM, Darren New wrote:
> On 6/19/2011 2:00, Chambers wrote:
>> 40pps :(
>
> The biggest (to me) unexpected slow-down was when I had something
> casting shadows that had a much-too-large bounding box, so every pixel
> was testing every light source for every shadow.

For me, it was when I tried to build a volumetric photon map.

I had a render which took 20 minutes or so. Turned on scattering media 
and volumetric photon maps, and now the photon map alone takes 45 
minutes to build. The actual render slowed to something absurd like 2 
pixels per minute.

At that point, I concluded that volumetric photon mapping was just too 
absurdly slow to ever use for anything.

Ten years later, I realise what the problem was. The photon map exceeded 
my computer's memory capacity, causing the puny laptop harddrive to swap 
like crazy for every individual pixel.

Perhaps if I get time, I'll go see if media sampling works now, ten 
years after I first tried it...

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