omino pixel blog

Easy Rain

Here’s a cute one. Nothing deep or advanced, but it was fun. It’s a way to get a very simple and cheap “rain” in After Effects.

1. Take a tiny bit of Noise, and blur it in one direction with Fast Blur.
2. This makes very, very dim “streaks”. Use Threshold to make them visible again.
3. Fast Blur it a little in both directions to make the edges smooth again.
4. Rotate the whole layer, for angled rain.

Easy peasy!

Here’s the AE setup for it. Trivial! Small adjustments of the parameters can get all sorts of interesting results.

What about CC Rain?

Well you know, apart from the joy (cussedness) of doing it the hard way… CC Rain makes relatively slow well-defined rain streaks. Depending what look you like, combining CC Rain with the more random movement described above is pretty nice, too.

If you like, here’s the self-contained tiny AE project. ==> just_rain.aep

Just an administrative note. I’ve got a set of free After Effects plugins available. The old web-page links were a bit confused, especially with respect to which ones work on After Effects CS3 and CS4, and which are for After Effects CS5.

The new link is https://omino.com/pixelblog/omino-ae-plugins/, and also appears as a “Page” in the blog nav column, and should be much clearer.

download ==> omino_spindala_32.pbk, an After Effects filter.

Always doing things the hard way. Needed a wheel with some symmetry, like so:

How else to do it than by drawing a circle with some blobs, and then treating it with… a handwritten pixel bender kernel:

I started describing its controls, but wouldn’t it be more fun to just try it out? Below is a slightly reduced version of the Pixel Bender kernel running in Flash.

Give it a spin! Try the parameters, or click Scramble a few times, or Go, to let it choose random parameters.

There’s no shortage of vaguely-trippy image manglers, these days, but that’s no reason not to indulge.

download: ==> omino staragon 32 <== a pixel bender filter Just recently, Dale Bradshaw posted a rounded-rect pixel bender plugin. Pretty nifty!

It got me thinking, What about other rounded-corner polygons? It was a bit of a puzzle. As with all Pixel Bender plugins, the question is, What color is this pixel? How does a given pixel know if it’s inside a rounded-corner pentagon or not?

I stuck to regular and stellated polygons to start. One solution goes like so:

• Divide the plane into pie-slices, one for each edge of the polygon.
• For each point, decide which slice you’re in.
• Decide if you’re inside or outside the edge.
• For the rounding… decide which corner you’re nearest
• Are you in the arc of that corner? If so, decide if you’re inside the rounding-radius.

Well, that was a bit of obsessive fun. Here’s a screen shot, including the parameter controls:

And here’s a little demo of it.

download: ==> omino staragon 32 <== a pixel bender filter