check failed issue

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Aug 23, 2023, 5:53:28 AM8/23/23
to pbrt

I'm using a realistic camera by importing some lens parameters. I'm rendering a typical pbrt scene with many trees and grass.  However very often I run into the following error. I'm not quite sure what this means and how to potentially fix it. Has anyone encountered this before? Any help would be greatly appreciated!

Rendering: [+++++++++                                  ]  (211.6s|790.2s)  F0822 23:06:23.561084 1083064 path.cpp:140] Check failed: beta.y() >= 0.f (-nan vs. 0)
*** Check failure stack trace: ***
    @     0x55f3cf063b19  pbrt::ScrambledRadicalInverse()
    @     0x55f3cf060e30  pbrt::RadicalInverse()
    @     0x55f3cf0642a9  pbrt::ScrambledRadicalInverse()
    @     0x55f3cee519fb  pbrt::ReadImage()
    @     0x55f3cef1924c  pbrt::HairBSDF::Sample_f()
    @     0x55f3cedbda24  (unknown)
    @     0x55f3cedbe102  (unknown)
    @     0x7efd06cd44a3  (unknown)
    @     0x7efd069c741c  (unknown)
    @     0x7efd06a477ac  (unknown)
    @              (nil)  (unknown)

Matt Pharr

Sep 3, 2023, 7:44:21 AM9/3/23
(That is a strange stack trace; it is likely incorrect.)

There is most likely a bug in pbrt somewhere causing floating-point not-a-number values to be generated.

Can you confirm that you are using an unmodified version of pbrt, or have you changed the code? Can you do a run with a debug build of pbrt? That will have many more runtime checks, one of which is likely to happen closer to where the bug is occurring.

Also, I’ve opened an issue for further discussion/debugging….


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