Add GLTF Scene Loader

[anishmgoyal]

Using the library cgltf, implements a GLTF scene laoder for BigWheels's scene graph.

Also, defines an interface for generic scene loaders, in case we come up with other ways of storing and loading scenes.

[Keenuts]

Just realized I never clicked "send review"

[Keenuts]

This code now being orphaned, and quite self contained (we don't break bigwheels by bringing it in), I would be fine to merge this as-is (minus the small fixes), and iterate from there, as long as this compiled on all 3 platforms.

[anishmgoyal]

This code now being orphaned, and quite self contained (we don't break bigwheels by bringing it in), I would be fine to merge this as-is (minus the small fixes), and iterate from there, as long as this compiled on all 3 platforms.

@Keenuts ehh - I don't mind trying to address the comments directly in this PR, that way nothing slips through unaddressed. I don't think this PR is needed too immediately

[anishmgoyal]

@Keenuts can you re-review discussions above?

[apazylbe]

I have to admit I mostly skimmed the code at the end. I left some notes (some mainly for the record, feel free to ignore or add your thoughts).

[Keenuts]

This code now being orphaned, and quite self contained (we don't break bigwheels by bringing it in), I would be fine to merge this as-is (minus the small fixes), and iterate from there, as long as this compiled on all 3 platforms.

@Keenuts ehh - I don't mind trying to address the comments directly in this PR, that way nothing slips through unaddressed. I don't think this PR is needed too immediately

Sure, we can address the open comments. But since this is a 4K Loc PR adding a new API with 0 tests, I think we'll miss many bugs anyway. So as long as nothing relies on this before it's proven to work, I'm OK merging this.

[apazylbe]

@Keenuts @anishmgoyal any objections to merging this as is and addressing the outstanding comments in a follow up?
This way @footballhead will be able to make progress on GLTF work

[anishmgoyal]

@Keenuts @anishmgoyal any objections to merging this as is and addressing the outstanding comments in a follow up? This way @footballhead will be able to make progress on GLTF work

Sorry - I've been distracted with other things. Merging this sounds good to me