NVIDIA OptiX ray tracing engine is an application framework for achieving optimal ray tracing performance on the GPU. Applications using OptiX can fail in ways that are difficult to diagnose: an invalid API argument, a black frame, or a GPU-side bug buried under thousands of concurrent threads.

Debugging facilities in the NVIDIA OptiX Toolkit (OTK) can help. OTK is a GitHub repository containing a set of utilities supporting workflows common in GPU ray tracing applications. OTK is licensed with a BSD 3-clause style license, so you are free to copy and modify any of the code.

This post covers two OTK debugging facilities: consistent checking of OptiX and CUDA API error codes and targeted device-side debug printing. OTK includes an example program, DemandPbrtScene , that shows device-side debug printing used in context.

How do OptiX logging and validation work?

Before getting to the assistance provided by OTK, some background on the OptiX log would be useful.…