Additional resources:

I know you are aware of notcurses. Aim to survive the notcurses-demo, it is a very good test of performance, Unicode support, 24-bit RGB, memory pressure, and images (both kitty and sixel).
If you choose to support sixel (perhaps from merging ayosec's graphics PR branch from alacritty), then you should also be aware of chafa . Among its encoders is an extremely fast high-quality sixel encoder. notcurses and chafa are the fastest encoders I know of, and have different performance characteristics on the high end. If you can keep up with both of them, then you will be in great shape.
If you choose either sixel or iTerm2, then you should also test against jexer . When I wrote Jexer's image backend, only 3 terminals survived its lots-and-lots-of-small-images approach. Now most terminals are working OK (though some still crash). If you retrofit ayosec's graphics PR from alacritty, it should work fine with Jexer-type output, but will not work fine for notcurses output due to how it treats partially-damaged images.

On a different topic, just so I don't spam you with junk:

Since you started from alacritty, you should be good with vttest now as they stopped crashing on it 5-ish years ago. But their coverage of vttest/VT100/xterm is still far from complete. If very good VT100/xterm coverage including VT52 submode is one of your goals, then you will need to go a bit past the Paul Flo Williams parser. (Specifically it does not have a state for the VT52 direct cursor address sequence, which isn't terminated like ECMA-48/ANSI X3.64 sequences are supposed to be.)

Looking forward to your success. :)

Support Kitty Image Protocol / MIME Types / Rendering #26

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