Andrew, Hai, Chris: this is a library Ryan and I were working on for a while.
The pinch stuff is most well thought out, and includes a mechanism for listeners
to say whether they claim a point or not.

The pinch stuff includes support for projecting pinches onto a sphere for
manipulating a 3D camera, which is probably of interest as it might save you
some time if you try to do something similar. The  2D pinch stuff here is more
straight forward and is a variation of the map-specific stuff in the
https://github.com/randomEtc/modestmaps-cinder project.

The double-tap stuff can/should probably be adapted to use the new Cinder
Timeline support. The issue is that you probably want to suppress the reporting
of single-tap events until a double-tap has fired (with e.g. a ~200ms delay).
This means re-working apps that already support single-tap before you can use
double-tap.

Other event support is really just sketched out, we had plans for:

* double tap / single tap 
* two-finger tap 
* two-finger double tap 
* tap and hold
* pinch/spread (zoom out, zoom in) (2+ fingers?) 
* 3 finger pinch (gather?) 
* two-finger rotation 
* three+ finger twist 
* one/two/three/four finger swipe 
* palm print :) 
* full multi-touch transform (a la modestmaps, with optional rotation)

...

To add this lib to an existing git-managed Cinder project do:

git submodule add git@github.com:bloomtime/CinderGestures.git blocks/CinderGestures

And then add the relevant folders (include) to your project. Don't add the
samples folder (I just add  everything and then remove the irrelevant bits).