Dithering with alpha to coverage

Up fairly early and got on with it. Still on anti-alaising. There’s a couple of extra bits in it as well. One of them is ‘alpha to coverage’. Now normally when you do an alpha test on a pixel you just test it against a threshold and do a discard. But when you are doing multi-sampling you can do a bit better as you have multiple fragments to play with. So you can take the alpha value and then dither it, this gives a nice sort of faded effect which looks like alpha-blending but isn’t. The fun thing you can do in more modern hardware is actually specify which fragments to use in the actual pixel shader, so you can do your own dither patterns. Well that was the excitement of my day.

Walked the dogs, yes both went. Went to Spin, which after yesterdays car crash of a class was nice to get back to normal. Came back and worked far too hard. Upgraded pfSense, due to all this who ha on bloody SSL leaking. I need to re-key all my certificates next, that’ll be an exciting evening. Fitted new hard drive to iMac, that’s an extra 4TB there. The blu-ray recorder doesn’t seem to work though.

Time for cheese, may be wine, may be wine and cheese. (See, dithering again.)

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