Classic ray tracing doesn’t do gi well, and gi is important for materials like blood that do lots of subsurface scattering. Also, blood is a fluid and with flu

Classic ray tracing doesn’t do gi well, and gi is important for materials like blood that do lots of subsurface scattering. Also, blood is a fluid and with fluids your often better off using a ray marching algorithm that can handle implicit surfaces than trying to do surface reconstruction