Integrating GPGPU Functionality into Scene Graphs

The concept of scene graphs is widely used in computer graphics to structure graphics-related entities, e.g. geometry, visual attributes as well as abstract data related to certain application requirements like object identifiers or manufacturing details. This paper presents a new method to incorporate General Purpose Graphics Programming Unit (GPGPU)-functionality into scene graph APIs. We define specific scene graph nodes in order to realize a flexible integration of GPU functionality at various levels of granularity without violating the programming paradigm inherent to scene graphs. We focus on current and upcoming compute APIs like CUDA, which are designed for GPGPU purposes. We further present the osgCompute framework that implements our concept and is based on the OpenSceneGraph API. CUDA is integrated into osgCompute via osgCuda. Our method is flexible in the sense that other compute APIs could be used instead. The advantages of our concept and ofosgCuda are demonstrated by presenting examples with different processing requirements.