Path tracing techniques usually focus on finding the most useful rays to trace, to focus only rays that hit a light (importance sampling).
RC is different, at least in 2D and screen-space 3D. It brute-force traces fixed sets of rays in regular grids, regardless of what is in the scene. There is no attempt to be clever about picking the best locations and best rays. It just traces the exact same set of rays every frame.
Full 3D RC is still too expensive beyond voxels with Minecraft's chunkiness. There's SPWI RC that is more like other real-time raytracing techniques: traces rays in the 3D world, but not exhaustively, only from positions visible on screen (known as Froxels and Surfels elsewhere).
Penumbra hypothesis is an observation that hard shadows require high resolution to avoid looking pixelated, but soft shadows can be approximated with bilinear interpolation of low-res data.
RC adjusts its sampling resolution to be the worst resolution it can get away with, so that edges of soft shadows that are going from dark to light are all done by interpolation of just two samples.
RC is different, at least in 2D and screen-space 3D. It brute-force traces fixed sets of rays in regular grids, regardless of what is in the scene. There is no attempt to be clever about picking the best locations and best rays. It just traces the exact same set of rays every frame.
Full 3D RC is still too expensive beyond voxels with Minecraft's chunkiness. There's SPWI RC that is more like other real-time raytracing techniques: traces rays in the 3D world, but not exhaustively, only from positions visible on screen (known as Froxels and Surfels elsewhere).
Penumbra hypothesis is an observation that hard shadows require high resolution to avoid looking pixelated, but soft shadows can be approximated with bilinear interpolation of low-res data.
RC adjusts its sampling resolution to be the worst resolution it can get away with, so that edges of soft shadows that are going from dark to light are all done by interpolation of just two samples.