Issue by Hixie
Wednesday Oct 21, 2015 at 16:48 GMT
Originally opened as https://github.com/flutter/engine/issues/1708

An AnimatedPerformance is a ticker plus forward()/reverse() methods, and exposes a value in the range 0..1 plus a direction and a change notification API.

A Curve should just be something that takes a value in the range 0..1 plus a direction and a change notification API, and exposes a value in the range 0..1 plus a direction and a change notification API (that it transparently forwards to the input's change notification API).

This would mean we would only need to accept one type rather than accepting a performance plus a curve everywhere, and consumers could chain performances and curves however they wanted. It would also mean you could have a "performance" that was slaved to another kind of input than a ticker.