* Minor clean-ups
- fix a couple usage of std::function
- fix a couple usage of std::string
- remove ALIGN_LOOP, which didn't work
- fix a couple explicit/noexcept
- virtual -> override
* Fix spelling typos and other minor clang-tidy
computeLightTree() takes a list of light as
a bitfield and produces a depth-first
binary tree array that can be used to efficiently
check which lights volumes contain a given z
coordinate in screen space.
Currently computeLightTree() produces the array
locally on the stack, which isn’t useful, but
before we can make use of it, a lot of other
things have to happen.
