Exceptions vs. error returns, quantified

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Today I got into a discussion regarding embedded programmers and their tendency to avoid exceptions in C++ (even after moving to new-school “embedded” systems such as smartphones, game consoles, and set-top boxes). The argument basically boils down to three things: code size, memory usage, and execution speed. So, rather than continue on without actually putting my beliefs to the test (the discussion basically centered around whether engineers are making assumptions based on how things were 15+ years ago), I decided to construct a minimal test which I think shows where the tradeoffs may be.

Note: The timing and memory analysis has been updated as of May 24, 2018.

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Affine HSV color manipulation

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Because the need for color manipulation comes up fairly often in computer graphics, particularly transformations of hue, saturation, and value, and because some of this math is a bit tricky, here’s how to do HSV color transforms on RGB data using simple matrix operations.

Note: This isn’t about converting between RGB and HSV; this is only about applying an HSV-space modification to an RGB value and getting another RGB value out. There is no affine transformation to convert between RGB and HSV, as there is not a linear mapping between the two.

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xmousekeys

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This is a simple program for moving the mouse cursor around from a script. Useful as something to bind to a key event in window managers which allow such a thing but don’t have built-in keyboard-mouse functionality (such as pwm).

xmousekeys.c