Return boolean from fill methods

[Manishearth]

This lets us do things like

if (fillPoses(spaces, poses)) {
  renderHand(poses)
}

Another part of #37, was missed in #44

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Preview | Diff

[Manishearth]

unsure if this one needs to be a bool too

[toji]

Might as well, for consistency. It's not going to be as frequently used as the return value from fillPoses, but it'll definitely bite someone if the return value is different between them.

[Manishearth]

Should the boolean be false when there are any null poses or false when there are all null poses?

[Manishearth]

/agenda to discuss if this is necessary

[toji]

enum XRTruthiness {
  'true',
  'false',
  'space_not_found'
};

😁

More seriously, though, I have an inclination to say that it should return false if any poses failed to resolve, since given the code snippet you posted seems extremely reasonable/likely but it could fall apart fast if the result has NaN's sprinkled throughout. Someone who is trying to handle NaNs correctly is going to be forced to loop through and check every value anyway, so there's little reason for them to check this value (aside from possibly a "you can take the fast path this frame" signal?)

[Manishearth]

That sounds good to me!

[Manishearth]

That makes this great for hands, but more annoying for anchors, where a false value would still mean you need to iterate through it, but maybe filtering it.

[cabanier]

I'm ok with returning false if any pose or radius fails to resolve.

[Manishearth]

Flipped the return value to be "if all are valid" instead of "if any are valid"

[Manishearth]

Okay, there seems to be consensus on merging this, and the radius thing can be improved after we fix #46 .