Change default interaction policy to always-allow

[pushmatrix]

From all of our user testing it seems clear that requiring focus on mobile to interact is not intuitive. @mrdoob said the same thing over at #479.

I do think we need a better heuristic for mobile (#479), and we should have the interaction policy be configurable (#500), but a sensible default should favor making it easy to interact with.

Thoughts?

[cdata]

This looks good. I think I would like to see this paired with a way for folks to opt-in to requiring focus until such time as we implement #479 . LMK if you have time to add an attribute for that, otherwise I can layer it on!

[pushmatrix]

I can likely handle it, but it will be next week.

[pushmatrix]

@cdata I added in the attribute interaction-policy so users can opt-in to requiring focus. This name came from the internal attribute that is currently being used.

• Is interaction-policy a good name for an attribute? Or should it be something like require-focus and have that just be a true/false?

• SmoothControls.ts and Controls.ts now both define the same InteractionPolicy. Doesn't seem DRY to me. Thoughts?

[cdata]

interaction-policy is a good name. I think attributes with explicit values are better than boolean attributes without values in a lot of cases (for the same reason that boolean method parameters are usually not ideal).

Agreed, there is a bit of repetition here. I think in the long-run, interaction-policy will be evolved or deprecated as we land on some solid built-in heuristics for interaction detection e.g. #479

[cdata]

One small change requested, otherwise looks great 🍻

[pushmatrix]

Changes made :)

[cdata]

Thanks for the contribution! 👍