[markostamcar]

Author here. Thanks and welcome :)

Dynamically Redefined Character Set (DRCS) was introduced with DEC VT200 and even though online information is scarce, there is enough there to make it work on a real machine.

Even more interesting are the Yugoslavian/Slovenian video terminals with their own custom graphics modes and features - it is a lost art but we at the Museum are working on bringing it back!

[markostamcar]

And there is also ReGIS / Remote Graphic Instruction Set by DEC - unfortunately none of our terminals support it.

[Tepix]

Yesh, i think some xterm programs do support it and i remember toying around with it in the 90s. That stuff was already obscure even then.