Something to look forward to: Adding ray tracing to classic games has been an excellent way to show off the difference it makes. Last week a modder posted a YouTube trailer that shows the feature employed on the original Half-Life. The modder plans to have it playable this year, though no specific date was mentioned.
Sultim_t says in the description of his trailer for Half-Life: Ray Traced that he will add real-time path tracing to Valve's seminal 1998 first-person shooter. The ray-traced effects include global illumination, reflections, refractions, and soft shadows.
Path tracing is similar to ray tracing but far more comprehensive and computationally expensive. The ray tracing in games like Cyberpunk 2077 or Resident Evil Village is mixed with traditional rasterization, only handling effects like global illumination or reflections. By comparison, path tracing renders the entire scene with ray tracing.
It takes so much horsepower that only games with relatively basic or aged graphics like Minecraft or Quake II RTX can use it at playable framerates. However, even those games need upscaling methods like DLSS to do it. Sultim_t doesn't mention any upscaling feature for Half-Life: Ray Traced.
Sulim_t previously developed a ray-tracing mod for Serious Sam, although this mod is based on a previous attempt to add ray tracing to Half-life. Sulim_t plans to release it on GitHub along with the source code when done. In 2019 Nvidia said it planned to bring ray tracing to more classic games but hasn't revealed any since.