Facilitating post-WIMP Interaction Programming using the Hierarchical State Machine Toolkit

Developing interactive programs is difficult because of the poor support for programming interactions in programming languages and the poor support for creative graphic design in traditional toolkits. This paper presents the Hierarchical State Machine Toolkit (HsmTk), a toolkit targeting the development of rich interactions. HsmTk has been designed to accommodate the needs of its users, namely programmers as well as interaction and graphic designers. It features a new control structure that makes interactions first class objects by extending C++ with hierarchical state machines. It also features the use of Scalable Vector Graphics (SVG) as the graphic language, enabling graphical designers to specify high-quality interfaces. Together, these features enable a tight coupling between graphic and interaction design by designers and software development by programmers. The paper provides examples illustrating the development process that results from using HsmTk.