Integer Ray Tracing

Abstract

Despite nearly universal support for the IEEE 754 floating-point standard on modern general-purpose processors, a wide variety of more specialized processors do not provide hardware floating-point units and rely instead on integer-only pipelines. Ray tracing on these platforms thus requires an integer rendering process. Toward this end, we clarify the details of an existing fixed-point ray/triangle intersection method, provide an annotated implementation of that method in C++, introduce two refinements that lead to greater flexibility and improved accuracy, and highlight the issues necessary to implement common material models in an integer-only context. Finally, we provide the source code for a template-based integer/floating-point ray tracer to serve as a testbed for additional experimentation with integer ray tracing methods.