On Mon, Mar 4, 2013 at 8:40 PM, Michael Marcin <mike.marcin@gmail.com>wrote:
I first ran across the term in Flash. I'm not sure if that is the origin but I think it has a large role in its popularity.
http://www.adobe.com/devnet/flash/articles/concept_tween.html
I believe it is the origin of the name but not of the functionality. Indeed before doing some flash few years ago, I didn't know that name was used. Once I knew the name, I discovered tons of libraries. The thing is before that, to me, it was value animation, applied either on graphics positions, alpha, effects intensity, sound volume or other effects, etc. But when you say value animation it feels weird so I guess everybody felt having a name like Tween(ing/er) was easier to identify what we're talking about. value animation is also too generic as it include things like steering-behaviours that really are a different (and more reactive) way of doing procedural animation. Joel Lamotte