omino pixel blog

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

download: ==> omino glass 32 <== a pixel bender filter There was a flurry of interest in "chromatic aberration" a while back, like here. I’d actually played with it a bit, simulating lens-effects, but only now have gotten around to weighing in on it.

The implementations I’ve seen work by splitting out your RGB and moving them around a little bit independently.

Here’s my weigh-in: Come on, people! The spectrum has more than three colors!

I find that five to seven is about right. I’ve implemented this combined with refraction into a pixel bender plugin.

Refraction happens when a ray of light changes its direction as it passes from one substance to another, if they have aaah, varying, that is, if they have different, um, refractive indexes. And that’s how aaah magnifying glasses work. See.

It looks like this.

The blue lines are rays of light moving up, or cast-sight-rays going down. It’s all very technical.

But I’ve got this Pixel Bender filter, right?

The filter takes in two images: a bump map (the refracting surface) and an image to view through the refraction. Here’s a bump map:

And here’s a source image:

Those chairs are known as “Chadwick Modular Seating”, from Herman Miller, designed by Don Chadwick, who later designed the Aeron chair, and that room hasn’t been that empty for, like, six years, after my girlfriend moved in and filled it up with shoes and stuff. So anyway.

And here’s the image, through the omino_glass Pixel Bender filter:

Now the fun part. Chromatic aberration happens when different colors are refracted by different amounts. Here’s the same image with just a touch of chromatic aberration applied:

Livens it up a little bit, yes?

The “flat” parts of the image, under the non-sloping parts of the bump map, appear undistored, and uncolored. But the distorted parts of the image have their colors splayed out a bit.

That’s chromatic aberration, comma, simulated.

By the way, you can get this effect in After Effects using CC Glass and overlaying multiple tinted copies, with slightly different settings for Height, and adding them back together. But that’s a lot of layers and settings to juggle; my pixel bender filter does it all in one at 32bpc instead of 8.

Here’s a test grid set with no basic refraction, and lots of chromatic aberration. This leaves the central green portion of the spectrum centered on the original image.

The inset image is the bump map.

We can see how omino_glass breaks the spectrum up into seven regions. It’s arbitrary, but I like the look.

And here’s a little demo showing the filter in motion, animated in After Effects, out on the ‘Tube.

download: ==> omino glass 32 <== a pixel bender filter Other chromatic aberrations of interest, from some of my favorite blogs: ae-tuts
maltaannon
satya meka

Glory

Time marches forward. Computers are faster, hard drives and screens are bigger, cameras are smaller.

My usual settings have grown from 8 bit, 640×480 to 32 bit 720p. (Yeah, I’ve lost my fear of nonsquare pixels.)

Adobe just announced After Effects CS5, and I’m happy to report that the Omino After Effects Suite is fully ported for Mac OS X, 64-bit, and getting ready to roll.

And they’ve started their migration from humble 8-bit processes to glamorous 32-bit floating point processes, as well.

Tragedy

The great tragedy is that CS5 broke backwards compatibility with CS4 plugins. Oh, there were Reasons, oh yes, there always are. And, oh, they’ve made it relatively easy for developers to recompile, which I’ve done. (Worked like a charm.)

But between Apple’s fickleness (68k, powerPC, Intel) and, now, this… there’s a trail of plugin corpses. Great sadness.

Some of my favorite Plugins don’t even exist for AE Intel Mac. Actually, the only ones I’ve paid for… WalkerFx’s stargate, and dvGarage’s dvMatte Pro. How I do wail!

Rays of Hope

But are things, overall, getting better? Oh yes, much better.

My CS5 plugins are Mac only, for now.

The Mac/Win CS4 versions will remain available. Or should I say, will remain on display in the Marketplace that all may witness their demise and death, their only crime having been to be compiled at the wrong place at the wrong time.

http://omino.com/sw/.

If you tried to download the Windows version of the Omino After Effects Suite and had a negative experience: Please accept my apologies. I jumped the gun on the “release”. Lessons learned (something about DLL’s and testing, thanks).

On the plus side: http://omino.com/sw/ominoAeSuite/ has the fixed download. Confirmed to download and run on 3, count ’em, 3 computers other than my own.

(The only issues were with download/unzip; once running, they are reliable and stable. More stable than Particle Playground ha ha.)

Especial thanks to Mike K at Muonics for dragging me kicking and writhing into the necessary knowledge of manifests, linker choices.