The goal of this first step is to break down the high-level tasks performed by people when playing the particular game – irrespectively of the medium they use to play it – as well as the things they do, the things they act on and the things they need to know. In this context, it is essential to focus on the basic logical game activities and constituents identifying their semantic attributes and relevant regulations independently of the way these can be physically instantiated to be accessible or usable to particular user groups.
As an indicative example, the result of the decomposition for the game of chess is illustrated in Figure 2, where tasks are divided in two broad categories:
In this step, the abstract tasks resulting from the previous step are mapped to multiple low-level, physical alternative interactive designs, meeting target user attributes. In this context, accessibility barriers that can possibly emerge in each task when performed by a particular user group are identified and suitable alternative interaction methods and modalities are selected. An example of how the abstract task entitled “Select piece” (from the example illustrated in Figure 2) can be mapped to alternative low-level, physical, alternative interactive designs is presented in Figure 3.