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SHA-256 in MySQL!

I eventually got sick of having to patch MySQL with the OpenSSL SHA-2 functions every time I updated it. Nevermind that there was a SHA2() function in MySQL 6.0, and that 6.0 got completely yanked, and...

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Pointless optimization

So I was looking at the macro used to calculate 16-bit parity in pure C without branching: It uses GCC’s handy compound statement syntax, but otherwise it’s plain old C. Let’s look at the 64-bit ASM...

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Missions of the Reliant: I’m haunted by coordinate systems!

As if all the mucking about with coordinates before wasn’t bad enough, next I had to deal with unit vectors, polar/Cartesian coordinate conversion, sign adjustment vs. trigonometric functions… you get...

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Floating-point makes my brain melt

Sometimes it’s better to do the obvious than try to be “correct”. How would you check if a floating-point variable x was zero? Common sense says x == 0.0 should work, right? But the compiler gets...

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Missions of the Reliant: Engine room, flight recorder visual, fifty-one point...

A QTKit-based video recorder is now integrated into the code. I tried about twenty ways to get it to record audio too, but between CoreAudio’s failings and QTKit’s limitations, nothing both sounded...

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