Category Archives: Uncategorized

How to Speak NeoPixel

Adafruit calls them NeoPixels, but their real name is WS2812 or SK6812. They’re handy little RGB LEDs with built-in controllers. They use a single-wire anisochronous self-clocking signal, so controlling them requires some precise timing. There’s an easy-to-use Arduino library available, … Continue reading

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Spooky nulls in an ArrayList

I had a crash reported for one of my Android applications. Thankfully that includes a stack trace, because I would never have found this bug without it. I learned something new about concurrently accessing an ArrayList.

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A Gentleman’s Orthonormal Basis Rotation

So you need to draw curved and bent pipe-tube-things. You can make a straight section with two rings of points; just orient one ring like so, the other ring like so, and draw triangles between them. For a curve, just … Continue reading

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Iterating Over a Triangulation in Java

Say you’ve got some points in a plane, and you’re fixin’ to triangulate them. Specifically, you’re going to generate the Delaunay triangulation with an incremental algorithm, and then of course you’re going to want the triangles and/or segments. Now say … Continue reading

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SNES Classic Teardown

If I made a Christmas wish-list, the SNES Classic would be on it. I finally found one on the store shelf. When I got it home I played me some Star Fox and Super Metroid, and then of course I … Continue reading

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