fast_float VS gammy

> Google put in significant engineering effort into "Ryu", a parsing library for double-precision floating point numbers: https://github.com/ulfjack/ryu

It's not a parsing library, but a printing one, i.e., double -> string. https://github.com/fastfloat/fast_float is a parsing library, i.e., string -> double, not by Google though, but was indeed motivated by parsing JSON fast https://lemire.me/blog/2020/03/10/fast-float-parsing-in-prac...

For those that don't know, gcc 12.x updated its float parsing logic to something similar to fast_float and it's about 1/6 of the cost presented here (sub 100 in the graph presented here). Strongly suggest using that library or upgrading the compiler if you need the performance.

This makes sense for integers but betware floating point from_chars - libc++ still doesn't implement it and libstdc++ implements it by wrapping locale-dependent libc functions which involves temporarily changing the thread locale and possibly memory allocation to make the passed string 0-terminated. IMO libstdc++'s checkbox "solution" is worse than not implementing it at all - user's are better off using Lemire's API-compatible fast_float implementation [0].

[0] https://github.com/fastfloat/fast_float

I'm a bit stuck on how to do the same thing in c++, due to containers only having a single type. The very inefficient way I'm currently doing it is by passing a program as a vector of strings, and then converting the string constants to doubles with the fast_float library.

Just above this comment is a merged PR, which references fast_float library: https://github.com/fastfloat/fast_float

Daniel Lemire @lemire (creator of the algorithm, author of the C++ implementation, and provided constant feedback to help guide the PR).

And out of 6,000 lines in the file, at least 3000 are other people's code: earcut for polygon triangulation and fast_float because .obj files typically contain a lot of floating point numbers so it's important to parse them quickly.

How this compares to https://github.com/fastfloat/fast_float ?

I tried to compare it against Daniel Lemire's excellent fast_float library. Fast float took about 180ms for the same program, and all I did was change "std" namespace prefix to "fast_float". It's a factor of 12 difference, at least my machine. I tried MSVC next, and it is a lot better, but it is still ~4 times slower than fast float. AFAIK, clang currently does not implement the feature at all.

If you don't mind a 3rd party lib until your stdlib updates, https://github.com/fastfloat/fast_float is best-in-class.

Been using this https://github.com/Fushko/gammy/releases on F35. Now that Fedora defaults to Wayland on Nvidia cards i can't use it anymore (I could if i went back to X11 i suppose). I have tried https://github.com/maximbaz/wluma but it doesn't seem to work on fedora, even when compiling it myself. Anyone got a similar software that does work? I hate getting flashbanged when opening a website with a white background at 23:00.

I installed Brightness controller and Gammy both of them are not working in Manjaro gnome but worked fine in Pop OS.

Check out gammy, LightBulb or CareUeyes. I use the last one.

You could try gammy with adaptive brightness it adjusts to your screen light levels and tries to normalize brightness.

gammy has this option, install it from the aur:

you can use a program that has auto-brightness option to achieve this, i use gammy for example, just uncheck the auto color temperature option because that is for night mode (reduces blue light in night).

Every time i try to adjust either the light colors turn too bright or dark areas too dark and i found a solution in software called Gammy that auto adjusts brightness based on the content on your screen.