In the previous chapter we covered postprocessing effects that enhance the lighting results with a series of 2D calculations in screen space. All the recipes in the previous chapter provide the essentials for enhancing the rendered scene's quality after it is fully lit. Postprocessing, however, is not the only group of calculations that are handled in screen space.
All the recipes covered in this chapter complement our lighting system in some way. As you will soon see, the line between what is considered as postprocessing and what is considered a screen space calculation is not always very clear, but in the end it is not really important as long as you get the resulting image you wanted.