Hello blenderheads, I have a present for you today: a rather hacky solution to blur using nodes.
Does it use multisampling? It doesn’t have to.
Does it make things blurry? Well, eh, grainy
How it works:
You distort the UV map by a random amount. This takes part of one image and places them in a radius somewhere around where you are expecting the image to show. This means that for a single pass you get grainyness, but don’t have to sample very much to get a large blur radius that looks acceptable
What it looks like:
And up close:
Yes it’s grainy, but compare that to the minimum of 3 passes to get any sort of blur using regular multisampling and where you can clearly see the samples.
What can you do with it:
Well the obvious one is blur textures, and all the good things this means (edge detect in textures etc.)
NoiseBlur.blend (1 MB)
I’ve implemented it as a node group that is easy to use and allows a configurable blur radius and seed.
Credit where credit is due:
This whole lot was inspired by a post of martinsh’s I can’t find at the moment. It was called ‘dithered blur’ or something to that effect.