RTX provides hardware primitives from which one could build portions of a global illumination solution. Lumen is such a full-featured, turn-key solution which I

RTX provides hardware primitives from which one could build portions of a global illumination solution. Lumen is such a full-featured, turn-key solution which I believe can run in "software" (as in not using dedicated ray tracing hardware functions) or can take advantage of hardware raytracing, including RTX, for some portion of its calculations.