I am working on a raytracing Java program for fun. Here's one rendering: [![enter image description here][1]][1]

As you can see I still have to implement anti-aliasing (and there are huge geometry problems I won't get in to). How would one go about this in a raytracing program, where the renderer doesn't really render lines, but individual pixels? Is it even possible? For example, in a scanline rendering, you could apply anti-aliasing after filling a triangle. But in a raytraced rendering, the program works pixel-by-pixel, and doesn't know where object's edges are, or where to smooth things out.


  [1]: https://i.stack.imgur.com/CSWU3.jpg