I am following the 1.6 tutorials using the 2.0 version of SFML, and I'm trying to use shaders. Instead of sf::PostFX which isn't there, I thought sf::Shader is the equivalent. Furthermore, I tried using the sf::Shader::SetTexture, which not only does not accept 'NULL' as its second argument so I don't know how to tell it to use the contents of the screen but half the functions in sf::Shader that are listed by visual studio don't seem to be in the documentation. sf::Shader::SetTexture isn't.
How can use the equivalent of postfx in 2.0?