Two days ago I added an optional bloom filter, which was easy to add, even though it’s a bit drawn out (takes 4 passes to make the final image). A lot of it was borrowed code from the blur shader. The bloom is exaggerated here for detail.
I pretty much figured out the steps needed to blur and add the colors myself. Where I needed some more help and insight was on how the brightness threshold should be calculated. Here are the references that I used: