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A comment on Rendering my (billiard) balls in a fragment shader. Parent comment

Re:Rendering my (billiard) balls in a fragment shader by zeristor on Sunday September 11, 2022 @04:03AM (#32797719)
Interesting point if it had been apparent it would have been an issue, at what point does a poor Pi become an issue?

What would a Pi of 3.0 do?

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Re:Rendering my (billiard) balls in a fragment shader by oever on Sunday September 11, 2022 @04:24AM (#32797815)
Here's a presentation show what happens to rendering in the game Doom when π has different values.

https://media.ccc.de/v/mch2022-236-non-euclidean-doom-what-h...

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Re:Rendering my (billiard) balls in a fragment shader by rzzzt on Sunday September 11, 2022 @05:11AM (#32798084)
A professor comes around and criticizes it as it is about to become law:

- https://en.wikipedia.org/wiki/Indiana_Pi_Bill

- https://www.straightdope.com/21341975/did-a-state-legislatur...

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Re:Rendering my (billiard) balls in a fragment shader by jffhn on Sunday September 11, 2022 @05:32AM (#32798198)
The value was superior to mathematical Pi (as is best float approximation, but not best double approximation), such as having 2*PI normalized into [0,2*Pi] by standard trigonometric functions (which use accurate approximations of Pi) would not preserve it and yield a value close to 4.2e-10, which could cause suprises (for example if angular ranges are defined as (start,end) and not (start,span)).
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Re:Rendering my (billiard) balls in a fragment shader by kaoD on Sunday September 11, 2022 @05:11AM (#32798086)
In this case not a lot happens since it's only used for Z rotation.
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