Serious answer: Posits seem cool, like they do most of what floats do, but better (in a given amount of space). I think supporting them in hardware would be awesome, but of course there’s a chicken and egg problem there with supporting them in programming languages.
I had the great honour of seeing John Gustafson give a presentation about unums shortly after he first proposed posits (type III unums). The benefits over floating point arithmetic seemed incredible, and they seemed largely much more simple.
I also got to chat with him about “Gustafson’s Law”, which kinda flips Amdahl’s Law on its head. Parallel computing has long been a bit of an interest for me I was also in my last year of computer science studies then and we were covering similar subjects at the time. I found that timing to be especially amusing.
No real use you say? How would they engineer boats without floats?
Based and precision pilled.
I know this is in jest, but if 0.1+0.2!=0.3 hasn’t caught you out at least once, then you haven’t even done any programming.
As a programmer who grew up without a FPU (Archimedes/Acorn), I have never liked float. But I thought this war had been lost a long time ago. Floats are everywhere. I’ve not done graphics for a bit, but I never saw a graphics card that took any form of fixed point. All geometry you load in is in floats. The shaders all work in floats.
Briefly ARM MCU work was non-float, but loads of those have float support now.
I mean you can tell good low level programmers because of how they feel about floats. But the battle does seam lost. There is lots of bit of technology that has taken turns I don’t like. Sometimes the market/bazaar has spoken and it’s wrong, but you still have to grudgingly go with it or everything is too difficult.
all work in floats
We even have float16 / float8 now for low-accuracy hi-throughput work.
Even float4. You get +/- 0, 0.5, 1, 1.5, 2, 3, Inf, and two values for NaN.
Come to think of it, the idea of -NaN tickles me a bit. “It’s not a number, but it’s a negative not a number”.
I think you got that wrong, you got +Inf, -Inf and two NaNs, but they’re both just NaN. As you wrote signed NaN makes no sense, though technically speaking they still have a sign bit.
IMO, floats model real observations.
And since there is no precision in nature, there shouldn’t be precision in floats either.
So their odd behavior is actually entirely justified. This is why I can accept them.
I just gave up fighting. There is no system that is going to both fast and infinitely precision.
So long ago I worked in a game middleware company. One of the most common problems was skinning in local space vs global space. We kept having customers try and have global skinning and massive worlds, then upset by geometry distortion when miles away from the origin.
How do y’all solve that, out of curiosity?
I’m a hobbyist game dev and when I was playing with large map generation I ended up breaking the world into a hierarchy of map sections. Tiles in a chunk were locally mapped using floats within comfortable boundaries. But when addressing portions of the map, my global coordinates included the chunk coords as an extra pair.
So an object’s location in the 2D world map might be ((122, 45), (12.522, 66.992)), where the first elements are the map chunk location and the last two are the precise “offset” coordinates within that chunk.
It wasn’t the most elegant to work with, but I was still able to generate an essentially limitless map without floating point errors poking holes in my tiling.
I’ve always been curious how that gets done in real game dev though. if you don’t mind sharing, I’d love to learn!
I’d have to boulder check, but I think old handheld consoles like the Gameboy or the DS use fixed-point.
Floats make a lot of math way simpler, especially for audio, but then you run into the occasional NaN error.
