Protovis composes custom views of data with simple marks such as bars and dots . Unlike low-level graphics libraries that quickly become tedious for visualization, Protovis defines marks through dynamic properties that encode data, allowing inheritance , scales and layouts to simplify construction. Protovis is free and open-source, provided under the BSD License .
Skyrails Blog Someone finally (thanks Christian) sent a mail in the skyrails-public mailing list, asking some questions, so I answered in the mailing list. It'll just become an FAQ here instead. > I am aware of that skyrails is a sprout of a PhD research