/*! \page driver_device_app Notes on the terms "driver", "device", and "app"

@ingroup api_notes

While we currently write the ray tracer on a single-memory image
machine, it will eventually run primarily on one or multiple devices
with separate address spaces. Thus, I think it is imperative to
directly design the entire system to suppor that later on. For that
reason, I will always differentiate between "host" and "device" when
referring to actual pieces of hardware, and between "app", "driver",
and "device" when it comes to differentiating different pieces of
software.

Wrt hardware: "host" is the host computer on which the application
run, and "device" the actual chip (or chips), on which the bulk of the
ray tracing is being done (i.e., LRB). Note however, that some parts
of the ray tracer may still live on the _host_ (like BVH builder,
potentially, and most certainly large parts of the API).

Wrt software: "app" is the actual applicatoin written by the end user,
which communicates with "the ray tracer" purely through the
API. "driver" is the part of the ray tracer that still runs on the
_host_, and which thereby can, in principle, share data with the
application. "device" is the part of the ray tracer that runs on the
actual device (eventually, LRB), and which operates in a different
address space. Eventually, the app will tell he driver what to do,
which will preformat all data (and potentially do some
pre-computatoins), upload data to the device, and then trigger the ray
tracer's device part to do the actual work.


Note: The naming is pretty much oriented on CUDA and GL...


*/