I already asked the same question in my post "Rain Forest" in p.b.i. but
didn't get an answer yet, so please excuse my cross posting.

My system is a 3.6 GHz Intel P4 with 2 GB RAM running under Win XP Home with
SP2. I was not able to render the scene Rain Forest with the official
POV-Ray 3.6 version. I allways got an error message "can not allocate xyz
bites for pigment_eval" or something like this as soon as I wanted to
include the second height_field (background) with it's trees in my render.

So I tried the same scene with MegaPOV 1.1 and there was no issue at all.
Parse time was faster by at least a factor 4 and render time (for the
limited scene that also worked with the official version) was faster too.

Did anybody else notice this behaviour before? Any hint would be
appreciated!

Regards and have a nice easter weekend, Christoph

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gerberc wrote:
> I already asked the same question in my post "Rain Forest" in p.b.i. but
> didn't get an answer yet, so please excuse my cross posting.

Nice image BTW.

> My system is a 3.6 GHz Intel P4 with 2 GB RAM running under Win XP Home with
> SP2. I was not able to render the scene Rain Forest with the official
> POV-Ray 3.6 version. I allways got an error message "can not allocate xyz
> bites for pigment_eval" or something like this as soon as I wanted to
> include the second height_field (background) with it's trees in my render.
> 
> So I tried the same scene with MegaPOV 1.1 and there was no issue at all.
> Parse time was faster by at least a factor 4 and render time (for the
> limited scene that also worked with the official version) was faster too.

That's quite unusual - in most cases the official compile is faster than 
MegaPOV.  Note MegaPOV contains a patch to decrease memory use of 
patterns so it might well be that rendering in MegaPOV uses 
significantly less memory than in official POV.  Does you scene define 
many textures, pigments etc.?

Maybe your OS is having trouble with handling that much memory (AFAIK 
all 32bit Windows version by default only address a maximum of 2GB 
although you can increase this to 3GB with a boot switch).  The 'can not 
allocate' messages result from the allocation of new memory failing 
(which means the OS fails to allocate memory for the program).

Christoph

-- 
POV-Ray tutorials, include files, Sim-POV,
HCR-Edit and more: http://www.tu-bs.de/~y0013390/
Last updated 27 Feb. 2005 _____./\/^>_*_<^\/\.______

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Christoph Hormann <chr### [at] gmxde> wrote:
> That's quite unusual - in most cases the official compile is faster than
> MegaPOV.  Note MegaPOV contains a patch to decrease memory use of
> patterns so it might well be that rendering in MegaPOV uses
> significantly less memory than in official POV.  Does you scene define
> many textures, pigments etc.?

There are only 4 leaf and 4 bark textures for the plants plus a complex
ground/rock texture. Additionally there are 2 height_fields on which I put
the plants using pigment_eval(). All in all much less than in most of the
scenes I did before without any problems.
Maybe the problems comes from the plants, the meshes have approx. 12 MB. On
the other hand peak memory for the render was only about 350 MB.

> Maybe your OS is having trouble with handling that much memory (AFAIK
> all 32bit Windows version by default only address a maximum of 2GB
> although you can increase this to 3GB with a boot switch).  The 'can not
> allocate' messages result from the allocation of new memory failing
> (which means the OS fails to allocate memory for the program).

I thought Win XP can handle 4 GB but I'm not sure and more specific I don't
know if there is a difference between the professional and the home edition
in this respect.

Regards, Christoph

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gerberc wrote:
> 
> There are only 4 leaf and 4 bark textures for the plants plus a complex
> ground/rock texture. Additionally there are 2 height_fields on which I put
> the plants using pigment_eval(). All in all much less than in most of the
> scenes I did before without any problems.
> Maybe the problems comes from the plants, the meshes have approx. 12 MB. On
> the other hand peak memory for the render was only about 350 MB.

Well - does memory use differ between official POV-Ray and MegaPOV?

> 
> I thought Win XP can handle 4 GB but I'm not sure and more specific I don't
> know if there is a difference between the professional and the home edition
> in this respect.

I am pretty sure all 32bit Windows versions default to 2GB address space 
for programs (the rest is reserved for the system).  If this can be 
changed with a boot option might differ between versions.

Christoph

-- 
POV-Ray tutorials, include files, Sim-POV,
HCR-Edit and more: http://www.tu-bs.de/~y0013390/
Last updated 27 Feb. 2005 _____./\/^>_*_<^\/\.______

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Well, here are the statistics for a small render without clouds, media fog
and background trees:

POV-Ray 3.6
parse time 2'28''
total render time 3'19''
peak memory 287563875 bytes

MegaPOV 1.1
parse time 0'54''
total render time 2'02''
peak memory 253942407 bytes

I made both renders with a freshly booted system because I noticed that
things get worse with POV-Ray 3.6 after each crashed render. As you see,
there are differences in memory used, but they are small (at least i.m.h.o.
and maybe because I don't understand much of th technical stuff).

Contrary to my estimation after a few crashes the render is a little bit
faster with the official version (51'' vs. 68''), but parse is
significantly faster with MegaPOV also on a freshly booted system.

Christoph

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