Direct X Ray Tracing: The Quest For The Holy Grail

THE NEXT GENERATION of Microsoft’s DirectX API, DirectX Raytracing (DXR), is intended to bridge the gap between rasterization and ray tracing, allowing for new and increasingly realistic renderings. But what exactly is ray tracing, and why do we need it?

 

A The holy grail of computer graphics has been figuring out how to create a perfect rendition of the world around us. Imagine trying model the way the world appears to your eyes. Photons bounce around, emitted from light sources such as the sun, light bulbs, our monitors, or are reflected off other objects. These photons reach the receptors in our eyes, and our brain interprets all of this as an image.

The problem with modeling this is that it all happens on an analog level. Photons are always being emitted, at different rates and wavelengths. A single light bulb emits around 2 x 1020 photons per second—never mind the sun. Simulating every photon bouncing around the world is impractical, and we need something else: ray tracing.