Inline Raytracing (Metal Support)
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Summary
DXR 1.0 traditionally works by dynamically executing shaders on hit/miss, via indexing into shader tables. DXR 1.1 introduces support for ‘inline ray tracing’ which allows to instantiate and configure ray queries in any shader stage, in order to traverse the provided acceleration structures, and implement the desired on hit / miss functionality.
In cases with lower shader complexity (fewer, less complex miss/hit shaders), Inline ray tracing allows to avoid the overhead of dynamic shader setup and execution, providing a convenient and efficient way to utilize hardware-accelerated ray tracing for more simplified use-case, as well as for generic implementations via compute.
Intended Outcome / Usecases
- Ray queries can be used in compute shaders in order to implement hardware accelerated ray-triangle intersection tests, when targeting capable Metal platforms.