Blender's path tracing engine, Cycles, supports realtime use in the editing viewport. Unless your machine is quite powerful, however, it doesn't render anywhere

Blender's path tracing engine, Cycles, supports realtime use in the editing viewport. Unless your machine is quite powerful, however, it doesn't render anywhere close to 30fps. Instead, it iteratively updates the viewport. It is fast enough that this is tolerable and useful for many workload+workstation combinations.