RasterShade is small simple R package that is available from GitHub. The package provides an interface to the package rayshader that allows using spatial data (as implemented by raster) instead of elevation matrixes. Besides that, the package allows calculation of surface shades for a given date and time or specific sun position.
Current versions of both packages can be installed using remotes:
remotes::install_github("tylermorganwall/rayshader")
remotes::install_github("JanCaha/rasterShade")