  Structured Adaptive Mesh Refinement (Structured AMR) enables simulations to
adapt the domain resolution to save computation and storage, and has become one
of the dominant data representations used by scientific simulations; however,
efficiently rendering such data remains a challenge. We present an efficient
approach for volume- and iso-surface ray tracing of Structured AMR data on
GPU-equipped workstations, using a combination of two different data
structures. Together, these data structures allow a ray tracing based renderer
to quickly determine which segments along the ray need to be integrated and at
what frequency, while also providing quick access to all data values required
for a smooth sample reconstruction kernel. Our method makes use of the RTX ray
tracing hardware for surface rendering, ray marching, space skipping, and
adaptive sampling; and allows for interactive changes to the transfer function
and implicit iso-surfacing thresholds. We demonstrate that our method achieves
high performance with little memory overhead, enabling interactive high quality
rendering of complex AMR data sets on individual GPU workstations.
