SBT Theoretical quesions?

[droettger]

@droettger

There is another elegant method to index into the SBT for the material and hold the per instance data separately.
The SBT hit records only need to contain the 32 byte header information which selects the material programs defining the material behavior (bi-directional scattering distribution function, BSDF), but none of the input parameters.
Which material is used can be directly selected with the OptixInstance sbtOffset value.
All other data required to define an OptixInstance’s geometry topology (vertex attributes and indices) and any other data like material parameters can be stored in separate device memory arrays and uniquely indexed by the user defined OptixInstance instanceId field which can be read inside the device code with optixGetInstanceId() which is available in IS, AH, and CH programs.

This smallest possible shader binding table architecture is now shown inside the rtigo10 example added to the OptiX 7 Advanced Examples:
https://forums.developer.nvidia.com/t/optix-advanced-samples-on-github/48410/8