Pipeline Rendering: Interactive Refractions, Reflections and Shadows

A coordinated use of hardware-provided bitplanes and rendering pipelines can create ray-trace quality illumination effects in real time. We provide recursive reflections through the use of secondary viewpoints, and present a method for using a homogeneous 2D projective image mapping to extend this method for refractive surfaces. We extend the traditional use of shadow volumes to provide reflected and refracted shadows as well as reflected and refracted lighting. A shadow blending technique is demonstrated, and the shadow and lighting effects are incorporated into our recursive viewpoint paradigm. Finally, we incorporate material properties including a translucency model to provide a general framework for creating physically approximate renderings. These techniques are immediately applicable to areas such as 3D modelling, animation and interactive environments to produce more realistic images in real time.