A Visual Programming Environment for Authoring ASD Therapy Tools

3D virtual environments can be used as therapy tools in patients with autism spectrum disorders (ASDs); however, the development of such tools is time-consuming. A 3D virtual environment development platform for such tools has been developed specifically for the South African context, because of the language and culture sensitivity of these therapy tools. The 3D virtual environment development platform has a Lua scripting interface for specifying logic in the virtual environments. Lua is a textual programming language, and presents a challenge to ASDs therapists’ ability to create therapy tools without engaging an expert programmer. The aim of this research was to investigate the design and implementation of a visual programming environment to support non-expert programmers in scripting within the 3D virtual environment development platform. Various visual program representation techniques, reported in literature, were examined to determine their appropriateness for adoption in our design. A visual programming language based on the “building-block” approach was considered the most suitable. The research resulted in the development of a visual script editor (VSE), based on an open source framework called the OpenBlocks library. The VSE successfully alleviated the syntax burden that textual programming languages place on non-expert programmers. The fitness of purpose of our VSE was exemplified in a sample 3D virtual environment that was scripted using the VSE. Despite the success, we argue that the applicability of the “building-block” approach is limited to domain-specific programming languages due to the absence of visual expressions for defining user-defined types, and for specifying hierarchy.