chess VS fpng

I think it's in the title: assets. The example case is replacing the BMP assets used by a game with QOI with a resulting 10x size reduction: https://github.com/skeeto/chess/commit/5c123b3

I think this functions as a test case. For a game as simple as a chess UI, PNG would probably be fine unless you're code-golfing on the final output binary or refusing to use common dependencies. But for some programs (e.g. large video games), preloading all your assets is very common and decoding speed can be crucial. Maybe the assets could even be left in compressed form in memory in order to reduce the system requirements? I'm not sure if this is common or not.

However, I don't really like the constraints this imposes, so I prefer my #include trick. In real programs I don't actually rely on xxd (part of Vim), and instead write a custom embed tool as part of the build. It's only a few lines of code to match the standard input behavior of xxd.

https://github.com/skeeto/chess/commit/9cc8c60 (depends on Vim xxd)

When the QOI format was first announced it wasn't clear that was even possible while keeping PNG format compatibility. But the fpng and fpnge C/C++ libraries showed it was, and today you can take advantage of those advances in a general purpose PNG library in Rust!

CRC is a table and 5 lines of code. That's trivial.

>zlib is 23k lines

It's not needed to make a PNG reader/writer. zlib is massive overkill for only making a PNG reader or writer. Here's a tiny deflate/inflate code [2] under 1k lines (and could be much smaller if needed).

stb[0] has single headers of ~7k lines total including all of the formats PNG, JPG, BMP,. PSD, GIF, HDR, and PIC. Here's [1] a 3k lines single file PNG version with tons if #ifdefs for all sorts of platforms. Removing those and I'd not be surprised if you could not do it in ~1k lines (which I'd consider quite simple compared to most of todays' media formats).

>Of course they're not common formats so you're stuck with complex formats like PNG

BMP is super common and easy to use anywhere.

I use flat image files all the time for quick and dirty stuff. They quickly saturate disk speeds and networking speeds (say recording a few decent speed cameras), and I've found PNG compression to alleviate those saturate CPU speeds (some libs are super slow, some are vastly faster). I've many times made custom compression formats to balance these for high performance tools when neither things like BMPs or things like PNG would suffice.

[0] https://github.com/nothings/stb

[1] https://github.com/richgel999/fpng/blob/main/src/fpng.cpp

[2] https://github.com/jibsen/tinf/tree/master/src

This was actually considered, and other libraries do ignore checksums, or at least have options to:

https://github.com/richgel999/fpng/issues/9

In the other direction, you can target a subset of PNG to get less optimized images but with QOI-like encode and decode speed: https://github.com/richgel999/fpng

On specific operations like screenshots for example the new version is WAY faster though. We were using stb_image_write.h but switched to fpng which promised 12-19x faster compression at smaller sizes. That and the fact that screenshot saving have now been given it's own thread so it now longer causes a small stutter like when it was on the main thread, means that screenshot are now near instantaneous.

I think QOI inspired the creation of https://github.com/richgel999/fpng which creates standard PNGs and compares itself directly to QOI.

BTW, today I found this fpng-fast PNG writer. There is a comparison with QOI in the readme.