Cute work. Of course there's tons of prior work in tabletop interaction; citing a few of the most famous:
- A full system:
"The reacTable: exploring the synergy between live music performance and tabletop tangible interfaces", Jordà et al., TEI 2007
- A toolkit that explores the problems that emerge when building collaborative UIs on tabletop:
"DiamondSpin: an extensible toolkit for around-the-table interaction", Shen et al. CHI 04
- A system of physical widgets that enable physical interaction with virtual controls on a tabletop:
"SLAP widgets: bridging the gap between virtual and physical controls on tabletops", Weiss et al., CHI 09
- An evaluation of children's interactions around tabletops in collaborative tasks:
"Around the table: are multiple-touch surfaces better than single-touch for children's collaborative interactions?", Harris et al. CSCL 09
There's many, many more. Tabletop interaction was probably at its most popular from ~2007 to ~2011 (I did my MSc. thesis on that near the end of that time); the best known consumer product being of course Microsoft's Surface (no, not the current one):
But then they killed it cause they didn't really know what to do with it, and then reused the name for the tablet/laptop hybrids we now know.
Regarding the "Tabla" project, it's a cool effort - but I'm always sad when the academic and more "artsy" (sorry, for lack of a better name) communities don't intersect. It'd be good to know what are the original contributions the authors see in their system, or what lacks in previous systems they think they address. The beauty of a paper is that long after the system can't be run anymore, the authors' notes and observations survive for the benefit of future researchers! Otherwise, everything these appears when the website/github repo/etc. goes down.
It seems like their project has 5 main activities: a pinball and tennis game, a "ball pit" physics demo of sort, a music composition system, and an animation system. The last 2 are the most interesting to me because of their creative nature - it'd be interesting to hear what aspects of their Tabla system works particularly well for these applications.
Additionally, how easy is it to build new activities for Tabla, and to what extent is it integrated in the system itself?