Whenever Sixel comes up, I always think about this guy who wrote terminal patches that allowed for Sixel support, as well as a library (libsixel) that generates them: https://github.com/saitoha
A couple years ago, it seemed like he was on a mission to patch every terminal in existence so that Sixel support was widespread. Seriously, half of his repositories have something to do with Sixel. Back then I was still on Windows, and when he patched mintty it was kind of crazy seeing bitmap graphics in my terminal for the first time.
It seems as though he hasn't made any commits in years, though. I wonder what happened to him. I always admired his interest in pushing these graphics, however old and arcane the protocol may be.
It turns out there is an active sixel branch of tmux. Scrolling is a bit broken (as in parts of images blank out when scrolling) but otherwise it works fine in mlterm (variable-width fonts ftw). So far they have merged past progress to a sixel branch on the upstream repo so it seems to be a matter of progress until it's merged.
The fact that xterm supports Sixel, at least through a build flag, once more confirms my belief that this old and battle tested terminal emulator very much rocks.
WordPerfect for UNIX™ now runs natively on Linux thanks to the amazing Tavis Ormandy's work, and he has got it generating print previews in the terminal using sixels:
The TRS-80 had 2x3 matrix block characters[0] in the character code range 128-191 that apparently were called squots (square dots). Combined with direct memory read/write, a decent CPU and fast basic made for some easy game dev of the snake and ski variety.
I experimented a bit with Sixel output for a home computer emulator, but good Sixel support in terminals is hard to come by (e.g. iTerm2 on Mac theoretically supports Sixels, but it's way too slow for any sort of realtime output beyond 4 colors).
I wish there was a proper (and widely supported) framebuffer standard for terminals with a 'chunky pixel format'.
Sixels is a paletted bitmap format, and (AFAIK) some terminals support more than 256 colors (e.g. see the screenshot in the readme here: https://github.com/saitoha/libsixel). But I guess the Wikipedia logo looks just fine with 256 colors.
A couple years ago, it seemed like he was on a mission to patch every terminal in existence so that Sixel support was widespread. Seriously, half of his repositories have something to do with Sixel. Back then I was still on Windows, and when he patched mintty it was kind of crazy seeing bitmap graphics in my terminal for the first time.
It seems as though he hasn't made any commits in years, though. I wonder what happened to him. I always admired his interest in pushing these graphics, however old and arcane the protocol may be.