Replace with forward declarations if needed and includes in .cpp that
now need them.
The idea here is to have our headers have the least amount of impact as
possible on our clients (e.g. compilation time).
* Add missing method to query the type of a light
* IcoSphere now generates front facing triangles
* Add a fairly generic sphere object to use in samples
it provides an ico sphere with normal, and reuses
the same vertex/index buffer for each new instance.
Each instance can have its own material, size and
position.
currently it’s not possible to change the # of
subdivisions.
* FilamentApp now provides a “default” pbr material
this makes it easier to create renderables for
testing.
* clean-up lightbulb and add spheres for each light
lightbulb now has less hardcoded things and it
spawns a small sphere for each light.
