In the process, not only are materials compatible with the path-traced renderer, they are also of a much higher resolution too. This involves a good understanding of art as well as coding because fundamentally, we want the materials to look realistic but at the same time to evoke the aesthetic of the original game. For path tracing to work and for light to propagate around a scene, textures need updating with elements like normal maps and material values - so the author of the path tracer has gone in and tweaked all the game's textures to have these characteristics. To get the game working with RT, author Sultim Tsyrendashiev delivers extensive modifications - not just in terms of the renderer (which is running via the Vulkan API) but also in terms of its core art assets too. However, as you'll see from the video and head-to-head screenshots on this page, the results of a transition to a fully path-traced experience are impressive. Yes, that's TFE, not Serious Sam HD - so it's a mod of the original game, largely bound by the limitations of the 2001 release. Taking an ancient, relatively simple 3D game and upgrading it into a fully path-traced graphical experience can be revelatory - and that's exactly what we see with this recently released, highly modified version of Serious Sam: The First Encounter. We've been down this route before with Quake 2, of course.
