Divide by zero with colorpict

radiance-general
1

Hi there

I'm running the the Debevec tutorial 2002 IBL program that uses beach.hdr with
the spheres on the pedestal and it's rendering with rview but I keep getting
these outputs and it takes ages. I tried changing the .hdr environment map but
the same thing happens. Anyone know what the problem is?

./rview: warning - compute error for colorpict "hdr_probe_image"
./rview: acos: domain error
./rview: warning - compute error for colorpict "hdr_probe_image"
./rview: Division by zero

Thanks for any help

Tarik

···

--
Tarik Rahman
PhD student, Institute of Perception, Action and Behaviour
School of Informatics
University of Edinburgh

2

Tarik

One thing I noticed when I did that exercise is that Debevec's world in <angmap.cal> is Y up and Radiance defaults to Z up.

I have no idea if this is a problem from the standpoint of generating the errors below, but it is something that I noticed.

I have gotten multiple "divide by zero" messages from rpict when using IBL as well. It just keeps on chugging through the calcs though. Greg?

Here is a link to my Radiance-IBL tests with the Debevec scene and some of my homegrown HDR's (thanks to Debevec's HDR shop and Greg's Photosphere).

http://www.3dfightclubforum.com/phpBB2/viewtopic.php?t=4328

good luck

kirk

···

On Feb 11, 2005, at 12:38 PM, Tarik Rahman wrote:

Hi there

I'm running the the Debevec tutorial 2002 IBL program that uses beach.hdr with
the spheres on the pedestal and it's rendering with rview but I keep getting
these outputs and it takes ages. I tried changing the .hdr environment map but
the same thing happens. Anyone know what the problem is?

./rview: warning - compute error for colorpict "hdr_probe_image"
./rview: acos: domain error
./rview: warning - compute error for colorpict "hdr_probe_image"
./rview: Division by zero

Thanks for any help

Tarik
--
Tarik Rahman
PhD student, Institute of Perception, Action and Behaviour
School of Informatics
University of Edinburgh

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3

I think that this error is resulting from one of the functions in the .cal (angmap.cal?) . In this case acos() is probably being fed a value outside the bounds -1 to 1, acos() is defined to return an error outside these bounds (man acos). An alternative is to use Acos() (see rayinit.cal), which I believe forces the boundary condition. It is likely that the subsequent divide by zero error is related to the domain error with acos(). Of course this is largely a guess based on the error output you indicated. If we had the cal to lookout then this might provide more information.

-Jack

Kirk Thibault wrote:

···

Tarik

One thing I noticed when I did that exercise is that Debevec's world in <angmap.cal> is Y up and Radiance defaults to Z up.

I have no idea if this is a problem from the standpoint of generating the errors below, but it is something that I noticed.

I have gotten multiple "divide by zero" messages from rpict when using IBL as well. It just keeps on chugging through the calcs though. Greg?

Here is a link to my Radiance-IBL tests with the Debevec scene and some of my homegrown HDR's (thanks to Debevec's HDR shop and Greg's Photosphere).

http://www.3dfightclubforum.com/phpBB2/viewtopic.php?t=4328

good luck

kirk

On Feb 11, 2005, at 12:38 PM, Tarik Rahman wrote:

Hi there

I'm running the the Debevec tutorial 2002 IBL program that uses beach.hdr with
the spheres on the pedestal and it's rendering with rview but I keep getting
these outputs and it takes ages. I tried changing the .hdr environment map but
the same thing happens. Anyone know what the problem is?

./rview: warning - compute error for colorpict "hdr_probe_image"
./rview: acos: domain error
./rview: warning - compute error for colorpict "hdr_probe_image"
./rview: Division by zero

Thanks for any help

Tarik
--
Tarik Rahman
PhD student, Institute of Perception, Action and Behaviour
School of Informatics
University of Edinburgh

_______________________________________________
Radiance-general mailing list
Radiance-general@radiance-online.org
http://www.radiance-online.org/mailman/listinfo/radiance-general

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Radiance-general mailing list
Radiance-general@radiance-online.org
http://www.radiance-online.org/mailman/listinfo/radiance-general

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