They are still limited in non-phone embedded contexts these days, leading to the ironic situation that the radar in your car that can override your brakes is running a much weaker CPU than your phone. RAM measured in the low megabytes.

Source: I write code for one of those radars and this constant appears in that code, alongside several other sqrt implementations of varying resolutions (8b, 16b, float). You are expected to use the least-resolution option in your algorithm, based on your analysis/testing. Same goes for trig functions.

I have to keep computer game development textbooks from the nineties and aughts around for reference material.

(he's a personal friend and a great guy!)