One-handed Real Time Strategy Game User Interface for Multi-Touch Devices

Historically, real-time strategy video games, such as Starcraft (1999) and Command and Conquer (1995), were intended to be played on desktop or laptop computers, with interfaces that afford the user dozens of keys and key combinations, mouse gestures including clicking and dragging, and several mouse buttons to further complicate the interface while allowing customization and a wide range of possibilities to the user. On a mobile multi-touch platform, there are constraints of limited visual real estate, shared with the touch command interface. Further constraints are presented when considering accessibility for players desiring one-handed operation. Game accessibility is a topic with a growing need, as those with disabilities are often unable to use commercially-available games due to user interface restrictions. To date, there has not been a significant commercial effort to enhance the usability of strategy games’ touch interfaces by removing redundancies and tailoring the game commands to these multi-touch devices – especially for use with only one hand. In this paper, we present a rapidlyprototyped user-centered design in a ten-week project of a real-time strategy user interface native for the iPad. The contributions of this project are the ability of the user to use one hand to interact with the system, a multi-touch interface design, and the ability to cancel orders. We confirm the effectiveness of the user interface using one hand with a pilot study. Although we hoped to be a universally accessible user interface for a real-time strategy game for the iPad, we found that it is impossible to separate the user interface from a polished game with real features.