https://github.com/grz0zrg/truespace
TrueSpace – 256 bytes intro in C code (Cordic, Linux, fbdev)
https://github.com/grz0zrg/truespace
Last synced: 3 months ago
JSON representation
TrueSpace – 256 bytes intro in C code (Cordic, Linux, fbdev)
- Host: GitHub
- URL: https://github.com/grz0zrg/truespace
- Owner: grz0zrg
- Created: 2021-03-16T23:00:07.000Z (over 4 years ago)
- Default Branch: master
- Last Pushed: 2021-03-16T23:16:08.000Z (over 4 years ago)
- Last Synced: 2025-01-29T12:28:31.769Z (5 months ago)
- Language: C
- Size: 2.06 MB
- Stars: 1
- Watchers: 3
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# TrueSpace by The Orz
### 256 bytes linux intro for Lovebyte sizecoding demoparty 2021
this doesn't use any libraries (not even the standard C library) and use two syscalls (open / mmap) to output to the Linux framebuffer device (fbdev), this also doesn't use shell / compression stub so it is a 'pure' standalone 256 bytes ELF
prototyped first with my [software graphics library](https://github.com/grz0zrg/fbg)
requirements:
* 32 bits /dev/fb0 (framebuffer) with supported resolution
* high quality: the framebuffer should be set to display resolution
how to run:
* switch to console with Ctrl+Alt+F2 (Ctrl+Alt+F1 to switch back to X)
* check /dev/fb0 is writable to you (or launch with sudo to bypass this step)
* check /dev/fb0 current resolution with fbset tool
* `clear` before running the program (not mandatory)
* run the appropriate binary
permission issue: add current user to either 'tty' or 'video' group or use 'sudo'
change graphical terminal resolution:
* check supported resolution with "vbeinfo" in GRUB command prompt
* "GRUB_GFXMODE=WxH" in /etc/default/grub (where W/H is a value)
* sudo update-grub
didn't test resolutions others than 1920x1080 so may have issues.
the goal was to test doing something midly interesting in 256b in C on Linux without compression stub / shell script, it use CORDIC based algorithm to output some kind of additive background stars
must be run at night with big display for best contrast ! (it is rather meh as a screenshot and couldn't capture fb0) here is a [phone video](https://www.youtube.com/watch?v=Zr8sXXdpvts)
with compression stub + truncation this goes to 239 bytes, the ELF header is roughly taking half the size, without the header the program code is ~80 bytes
code by grz built with GCC v7.5.0
greetings to all sizecoders
12/03/2021