Issues in combining marking and direct manipulation techniques

The direct manipulation paradigm has been effective in helping designers create easy to use mouse and keyboard based interfaces.The development of flat display surfaces and transparent tablets are now making possible interfaces where a user can write directly on the screen using a special stylus.The intention of these types of interfaces is to exploit user's existing handwriting, mark-up and drawing skills while also providing the benefits of direct manipulation.This paper reports on a test bed program which we are using for exploring hand-marking types of interactions and their integration with direct manipulation interactions.