glycose: sugar over the gly format

This repo implements a few helpers around the Gly inline graphics format seen in some Hundred Rabbits projects. You'll need a Zig 0.8+ compiler to run this stuff.

• gly2pbm converts a series of Gly bytes into Portable BitMap data. Currently, only P1 (uncompressed ASCII) is generated (PBM can optionally be encoded into a binary P4 format, for example by ImageMagick). It has no command line arguments, or indeed any configurability at all. Pipe valid Gly data into stdin, out comes P1-encoded PBM text on stdout.

$ zig build -Drelease-safe

# copy zig-out/bin/gly2pbm anywhere in your $PATH, perhaps ~/bin (if
# applicable) or /usr/local/bin

# boxgly.gly is a binary blob based on the drawing at
# https://wiki.xxiivv.com/site/gly_format.html provided for your convenience
$ gly2pbm < boxgly.gly > boxgly.pbm

# now you can use imagemagick to make it back into a PNG, perhaps:
$ convert boxgly.pbm boxgly_after_glycose.png

# there's no diff between devine's reference image and our generated
$ compare -verbose -metric AE '(' boxgly.png -colorspace gray ')' '(' boxgly_after_glycose.png -colorspace gray ')' boxgly_diff.png
# > boxgly.png PNG 32x32 32x32+0+0 8-bit sRGB 698B 0.000u 0:00.000
# > boxgly_after_glycose.png PNG 32x32 32x32+0+0 8-bit Gray 2c 325B 0.000u 0:00.000
# > Image: boxgly.png
# >   Channel distortion: AE
# >     gray: 0
# >     alpha: 0
# >     all: 0
# > boxgly.png=>boxgly_diff.png PNG 32x32 8-bit Gray 698B 0.000u 0:00.000

# what if you have a very high DPI monitor and 32x32 bitmaps are unreadable? #
# https://github.com/visioncortex/vtracer CLI to the rescue. with these
# arguments, the output will still look like a bunch of square pixels, just
# cleanly zoomed. think like a bitmap font that was pixel-doubled to @2x scale
$ vtracer --input boxgly.pbm --output boxgly.svg --preset bw -m pixel -f 1

Boring Legal Bullshit

The boxgly.png image refered to in the unit tests, its binary representation in boxgly.gly used as an example, as well as the Gly format description itself, are, as far as I can tell, licensed CC BY-NC-SA 4.0 upstream. As for my own code (everything else in this repository):

Released by klardotsh under your choice of the Guthrie Public License (https://web.archive.org/web/20180407192134/https://witches.town/@ThatVeryQuinn/3540091) or CC0-1.0 (https://creativecommons.org/publicdomain/zero/1.0/)

Anybody caught forkin it without our permission, will be mighty good friends of ourn, cause we don't give a dern. Publish it. Write it. Fork it. Push to it. Yodel it. We wrote it, that's all we wanted to do.