Hi,

I tried rendering Insert Menu bitmaps with POV-Ray 3.7 beta 7 and I got
quite dark images. Is this a bug with gamma correction? I saw in "Known
issues which will be fixed" that "There are some differences in the way
gamma correction works." so maybe this is a known bug.

I also got some odd artefacts with the crackle pattern in the insert menu.
It looks like a tiled boxed pattern (!) with noise (like interference). I
will post an image to beta-test.binaries.
That "interference" can also be seen in camera/normal.pov.

Another thing, camera/focalblur.pov and the focal blur in the
insert menu seem to hang povray, is it because of AA and my lack of
patience? I couldn't see any rendered block in 10 minutes! (Pentuim IV
3GHz).

Tested on the 32-bit executable.

Thanks for this great raytracer!
Nicolas

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About the focal blur item in the insert menu, I just noticed that POV-Ray is 
still rendering and using CPU but the Stop button in the toolbar changed to 
Run!15 minutes so far and still no rendered block!

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Nicolas Alvarez wrote:
> About the focal blur item in the insert menu, I just noticed that POV-Ray is 
> still rendering and using CPU but the Stop button in the toolbar changed to 
> Run!15 minutes so far and still no rendered block! 

Yes, because in POV-Ray 3.7 focal blur can finally be used with 
anti-aliasing.  In POV-Ray 3.6 and earlier focal blur disabled anit-aliasing 
because the two features were not compatible with each other.  Focal blur 
already takes long to render without anti-aliasing, but with anti-aliasing 
on it takes even longer.

	Thorsten

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Nicolas Alvarez wrote:
> I also got some odd artefacts with the crackle pattern in the insert menu.
> It looks like a tiled boxed pattern (!) with noise (like interference). I
> will post an image to beta-test.binaries.
> That "interference" can also be seen in camera/normal.pov.

Yes, this is a known "problem".  Actually it has to do with various design 
flaws in the "crackle" algorithm that make it completely incompatible with 
multithreading.  As such, more complex changes are needed to make it to work.

	Thorsten

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news:42e7f5c9$1@news.povray.org...
>
>  Focal blur already takes long to render without anti-aliasing, but with 
> anti-aliasing on it takes even longer.

But I have a 3 GHz computer, I tried the camera/focalblur.pov scene 
*without* antialias at 160x120, I got no pixel in 5 minutes (I stopped the 
render after that time). I just rendered the whole image in a 800x600 
resolution using POV-Ray 3.6.1 (no antialias, of course) and it took 31 
seconds.

Appart from that, once I start the render in 3.7, if I stop it, POV-Ray 
hangs! I'm using the 32 bit version. (let me ask, what is SSE?)

Happy coding :D

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"Nicolas Alvarez" <nic### [at] gmailbestwebmailcom> wrote in message 
news:42ec2412@news.povray.org...
>

> news:42e7f5c9$1@news.povray.org...
>>
>>  Focal blur already takes long to render without anti-aliasing, but with 
>> anti-aliasing on it takes even longer.
>
> But I have a 3 GHz computer, I tried the camera/focalblur.pov scene 
> *without* antialias at 160x120, I got no pixel in 5 minutes (I stopped the 
> render after that time). I just rendered the whole image in a 800x600 
> resolution using POV-Ray 3.6.1 (no antialias, of course) and it took 31 
> seconds.
>
> Appart from that, once I start the render in 3.7, if I stop it, POV-Ray 
> hangs! I'm using the 32 bit version. (let me ask, what is SSE?)

SSE is Streaming SIMD (Single Instruction Multiple Data) Extensions; which 
means processing more than one thing at a time, as simply as I understand 
it.

I checked that focalblur.pov and the same thing happened here. Stopping the 
render doesn't stop POV from using 99% of the CPU and when it finally closes 
it pops up a box with the following:
-------------------------------------------------------------------
Microsoft Visual C++ Runtime Library

Runtime Error!

Program: Program Files\POV-Ray for Windows v3.6\bin\pvengine*.exe

This application has requested the Runtime to terminate it in an unusual 
way.
Please contact the application's support team for more information.
--------------------------------------------------------------------

* happens with both the 3.7 beta 7 or the sse2.

XP HE SP2; Intel P4-M 2.0GHz

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> SSE is Streaming SIMD (Single Instruction Multiple Data) Extensions; which 
> means processing more than one thing at a time, as simply as I understand 
> it.

More precisely, it allows you to perform the same mathematical operation 
on several numbers simultaneously. (Which is probably very useful for, 
say, vector calculations - except that I imagine POV-Ray does all that 
kind of thing at very high precition, which SSE2 won't support.)

FWIW, SSE2 is an extension of SSE is an extension of MMX. In case you 
wondered.

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