high performance computing on graphics processing units: hgpu.org

Graphics programming sees widespread use across a number of industries, from video games to medical imaging. Because of the unique needs of graphics programming, specialised tools are required to aid in the debugging of graphics programs. While there are a number of well-maintained and wide-spread general-purpose debugging tools, the range of available graphics debuggers is much smaller, to the degree that it is sometimes hard to find appropriate tools. Given that graphics debugging is a dificult and time-consuming activity, research into more effective ways to support it are warranted. This thesis details the implementation of GLDebug, an OpenGL debugging tool that implements the novel feature of using historical information to assist with graphics debugging. GLDebug provides the ability to capture and recall OpenGL state and function call information. Users of GLDebug can retrace the graphics state history of OpenGL applications and compare different recorded states, which may come from different applications. State differences are made clearly visible, so that the source of state-based errors can be tracked down more easily. The thesis describes the knowledge required to implement a graphics debugging tool: how OpenGL information is captured, why this is dificult, and the limitations on information that can be captured. Furthermore, it describes how state information can be managed and made accessible to the programmer to support debugging. GLDebug has been evaluated in a pilot study. The results of the pilot study are promising: the participants of the study found the tool helped them when working on four OpenGL debugging tasks. All participants commented favourably on the support for tracking and analysing state history. The study also provided feedback and information that is useful in guiding the future development of the project.