You can write a ray tracer in a weekend. http://in1weekend.blogspot.com/2016/01/ray-tracing-in-one-weekend.html?m=1 http://in1weekend.blogspot.com/2016/01/ray-

You can write a ray tracer in a weekend. http://in1weekend.blogspot.com/2016/01/ray-tracing-in-one-weekend.html?m=1 http://in1weekend.blogspot.com/2016/01/ray-tracing-in-one-we... Improvements to commercial render engines today are often these days about adding new features and improving end user workflows. Here's last year's SIGGRAPH talk from Renderman. https://youtu.be/iDUV4ISCklA https://youtu.be/iDUV4ISCklA Commercial end users include digital art studios and other advanced users. In-house teams of specialists will use low-level APIs to achieve desired results. Render engines often more like a software development platform than a video game engine. The CG industry is constantly changing, these days a lot of effort seems to be aiming toward standardization and interchangeably as pipelines become more complex and software becomes increasingly specialized. (Zbrush, Maya, Mari, Houdini, Katana, Nuke.) A render engine will have to support several of these DCC packages and ensure artists get consistent results. Render engine speed improvements still play an important role in development, but it's most noticeable in areas that are outside of the traditional "path tracing" parts. This is things like subsurface scattering (the red glow of a flashlight behind your fingers), volumetrics (smoke and steam), and caustics (shimmering light on the table when a water bottle sits in the sun). The "ray tracer in a weekend" parts are very thoroughly optimized, but you do see innovation now and again with developments in importance sampling methods. What you say is true in this sense: modern render engines are still just as CPU intensive as ever and you still need massive server farms to create final frames. A more modern development is GPU-based render engines such as Redshift, Octane and Blender's Cycles. These engines are subject to the limitations of GPU memory - unlike a server where you could pop in a TB of RAM if necessary, GPU render engines are not currently able to handle extremely complex scenes like hero assets with tens of GB of textures, entire cities worth of geometry and so on. This Unreal Engine feature is a slightly different world. This isn't a raytracer in the sense of what I've been describing above, what it's doing is adding a layer of reflective effects, computed with raytracing, on top of ordinary "game engine", where in theory you could add controls to manipulate the camera with your mouse and keyboard and look around. To hit 30fps, the trick is adding just a little bit of reflection to improve the look, and setting up assets do that the approximated effect looks appealing and convincing. The machine they ran this on would cost nearly $100k, though the cost of creating professional assets specifically tuned for this specialized environment would rival that. However for an architecture studio trying to make a pitch showing a stunning interactive demo of their design, the economics are nearly there. And on a wider scale, this same technology could add extra pop to glass, metals, and liquids in next gen video games on a more modest gaming rig.