Radiative heat transfer of absorbing, emitting and scattering media and of diffuse and specular surfaces is analyzed by a generalized numerical method: radiation element method by ray emission model, REM2. Arbitrary thermal conditions can be specified for each radiation element. A generalized radiative heat transfer analysis can be achieved without recognizing participating media and surface elements by introducing the ray emission model and extinction, absorbing and diffuse scattering view factors. A torus plasma in a large helical device for the research of a fusion reactor is analyzed, in which plasma is approximated as a gray participating medium and a specular and diffuse surface is assumed for the vacuum chamber. The dimensionless temperature distribution of the modeled plasma and the dimensionless surface heat flux distribution on the wall of the vacuum chamber are presented.