I don't think we covered texture antialiasing with respect to raytracing, but we estimate the footprint area in raytracing by sending out "auxiliary" rays that are slighly shifted from a camera ray. This is explained in chapter 10 of pbrt: http://www.pbr-book.org/3ed-2018/Texture/Sampling_and_Antialiasing.html
I don't think we covered texture antialiasing with respect to raytracing, but we estimate the footprint area in raytracing by sending out "auxiliary" rays that are slighly shifted from a camera ray. This is explained in chapter 10 of pbrt: http://www.pbr-book.org/3ed-2018/Texture/Sampling_and_Antialiasing.html