Warp <war### [at] tagpovrayorg> wrote:
> clipka <ano### [at] anonymousorg> wrote:
> > Warp schrieb:

> > >   As for POV-Ray itself, I bet the limit is 2147483648x2147483648 pixels
> > > (or maybe even 4294967296x4294967296 pixels).

> > On contemporary x64 machines, the limit will be much smaller - some 4e6 
> > x 4e6 pixels; more than that, and you'll crash through the 256 TeraByte 
> > address limit (contrary to legend, contemporary x64 processors only 
> > support 48-bit addresses, despite the architecture being designed for 
> > future extensibility to full-fledged 64-bit addresses).

> > Windows will not allow more than some 7e5 x 7e5 pixels (8 TB), while 
> > Linux will not go beyond some 3e6 x 3e6 pixels (128 TB) due to 
> > per-process address space limits.

>   But those are not limitations of POV-Ray, they are limitations of the
> hardware and/or operating system.

>   If POV-Ray were to be compiled on a system without those limitations,
> it could probably achieve images of those sizes (in theory, of course,
> because in practice it would take millenia to render such an image, as
> noted elsewhere).

  Actually, thinking about it, you confused me.

  POV-Ray doesn't need to keep the entire image in memory in order to render
it (after all, POV-Ray was developed on systems with limited amount of memory,
yet was able to render images larger than any conceivable RAM size back then).

  Thus it's perfectly possible for POV-Ray to render a 2^31 x 2^31 pixels
large image even on a system which limits memory addresses to be smaller
than that.

  (Of course you won't be able to *save* that image anywhere because you
would encounter limitations in the file system. But that doesn't stop
POV-Ray from *rendering* the image.)

-- 
                                                          - Warp

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