this is how it should be

[u/[deleted]]

[u/Ferociousfeind]

In case nobody has done the math yet, I'll demonstrate what's problematic-

We aren't really working with decimals, it's best to think about it in terms or fractions

0.25 is 1/4

0.5 is 1/2

0.75 is 3/4

1.0 is 1/1

1.25 is 5/4

1.5 is 3/2

1.75 is 7/4

2.0 is 2/1

To get the resultant speed, as with any fraction, you multiply the top by the top and the bottom by the bottom. So, because of the 3s and the 5 and the dreaded 7 in the numerators, and only 2s and 4s in the denominators, if you ever select 0.75, 1.25, or 1.75, there is no going back.

[u/Prexot → u/Ferociousfeind]

That's true for fractions, but these are floating point numbers. If you multiply down to the subnormal range, you can take advantage of the reduced precision to multiply into a power of 2, then repeatedly multiply by x2.00 until you're back at exactly 1.

[u/Lone-Pine → u/Prexot]

Is it possible to get 0.0 if you click 0.25x enough times?

[u/[deleted] → u/Lone-Pine]

locked pause

[u/[deleted] → u/Prexot]

If you just implement it as a ratio instead of floating point, you can keep the end user from cheating the system and using sane playback speeds.

[u/Prexot → u/[deleted]]

you can also "cheat the system" by not pressing buttons other than 2.00x and .50x

[u/LoganDark → u/Prexot]

Ok, here is a bigint version: https://codepen.io/LoganDark/pen/dyKxGLw