Fun With ClearType

Text anti-aliasing is one of the the subtle things that makes modern computers much nicer to use than their ancestral 1990's era counterparts. It makes text render on screen without hard edges. It uses some trickery to do that, carefully choosing which colored elements around the text glyphs to give them a smooth looking appearance. Closely examining the characters onscreen (lean in really close, get a magnifying glass, it's happening on your screen right now, I guarantee it!) shows slight blue, green, and red tones in places that blend to gray when you're further back. This gives the impression of sub-pixel size features from a distance, tricking your brain into thinking you see things that really aren't there.

On windows, the piece of code that handles the text render is called ClearType.

Sadly, cleartype doesn't seem to know about monitor rotation, so having the color elements stacked vertically instead of horizontally can yield some interesting results. For instance, some character elements can actually vanish. This happens text is rendered on a color background with a rotated screen, thin vertical lines completely disappear.

Rotated Display:

Normal Display:

In normal rotation, there is a faint hint of darkness where the vertical bar on the * should be, but on the rotated display, it's just plain gone. When I first saw it, I wondered why there was a multiplication sign displayed when I pushed Shift-8.