Determine which animation tools to include in the framework

[skoolbus39]

Some tools to consider:

• Animate.css
• Anime.js
• Animista
• Barba.js
• Bounce.js
• Dynamics.js
• GSAP
• Matter.js
• MoJS
• Popmotion
• Rellax
• ScrollReveal
• Spirit
• Wait! Animate
• Wick

When considering the above (or others), keep in mind the emerging Intersection Observer API, which I think we should take advantage of. More info about Intersection Observer: 1, 2, 3, 4

We also need to ensure that any animations included do not introduce jank.

[skoolbus39]

We've used—and liked—skrollr here at UNL, but unfortunately, it is no longer under active development and, as such, I would not recommend its inclusion.

skrollr hasn't been under active development since about September 2014 (check out the contributions graphs on https://github.com/Prinzhorn/skrollr/graphs/contributors) and I don't have any plans for doing major changes to it. Please consider this before using skrollr in production as problems with new browser versions, especially on mobile, will most definitely surface. To be honest, mobile support always sucked (because mobile browsers are hard) and you shouldn't compromise UX for some fancy UI effects. Ever.

[skoolbus39]

Basic, scroll-based animations (#367) are included in DCF Core, but other more complex animations can be added at the theme level.