This is the beginning of adding ECS to QF. While the previous iteration
of hierarchies was a start in the direction towards ECS, this pulls most
of the 3d-specific transform stuff out of the hierarchy "objects",
making all the matrices and vectors/quaternions actual components (in
the ECS sense). There's more work to be done with respect to the
transform and entity members of hierarchy_t (entity should probably go
away entirely, and transform should become hierref_t (or whatever its
final name becomes), but I wanted to get things working sooner than
later.
The motivation for the effort was to allow views to use hierarchy_t,
which should be possible once I get entity and transform sorted out.
I am really glad I already had automated tests for hierarchies, as
things proved to be a little tricky to get working due to forgetting why
certain things were there.
The parsing of light data from maps is now in the client library, and
basic light management is in scene. Putting the light loading code into
the Vulkan renderer was a mistake I've wanted to correct for a while.
The client code still needs a bit of cleanup, but the basics are working
nicely.
While there's currently only the one still, this will allow the entities
to be multiply queued for multi-pass rendering (eg, shadows). As the
avoidance of putting an entity in the same queue more than once relies
on the entity id, all entities now come from the scene (which is stored
in cl_world in the client code for nq and qw), thus the extensive
changes in the clients.
It holds the data for a basic 3d camera (transform, fov, near and far
clip). Not used yet as there is much work to be done in cleaning up the
client code.
