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0 pointssmallnamespace9y ago0 comments

> A monitor does not quite deliver perfect squares,

Monitors don't display colored squares, period:

https://upload.wikimedia.org/wikipedia/commons/4/4d/Pixel_ge...

Our cone cells also don't see colored squares, and in fact each color's distribution is random:

https://askabiologist.asu.edu/sites/default/files/resources/...

In fact, CRTs phosphors didn't even correspond to logical computer pixels. If your CRT resolution was lower than the maximum phosphor grid resolution of the CRT mask, then a single pixel would indeed spread across more than one tri-color phosphor group.

Signal theory points reminds us that 'square pixels' are just an arbitrary shortcut. We could equally well describe them as hexagons, ovals, or rectangles, or make the grid positions random, and monitors would work just as well. That's why when you blow up a and render it as a giant square with exact edges, it's a very misleading and arbitrary choice.

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3 comments · 1 top-level

lmm9y ago· 2 in thread

But at no point, either in the CRT or in the human eye, do the ringing artifacts actually show up. So any pipeline that renders those when you blow the pixel up is worse than rendering just a giant square.

smallnamespaceOP9y ago

They do. If you try to draw a white pixel in the middle of a black background on a CRT, the white bleeds around in a small circle, and if look at a point light source in a totally dark room, you will see a small halo around it. These are both ringing artifacts.

lmm9y ago

You see faint light around the pixel/light source. You don't see the edges of the pixel/light source as brighter than the center. Do you? (Can't check right now but it's not how I remember seeing things)

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