@pitrh

Exotic Silicon is making the mistake that we all have made, of getting ITU T.416 wrong.

I hope that no-one merges that code, because it would be baking erroneous control sequences into #OpenBSD.

Most of the rest of we terminal emulator authors have been though the process, and by now have switched to the correct control sequence that T.416 actually specifies.

It requires colons for sub-parameters, and there is a colour space sub-parameter.

#ExoticSilicon #TerminalEmulators #T416

@RL_Dane @teamtuck

XTerm, urxvt, GNOME Terminal, and Konsole all have it. As has my terminal emulator. You just have to output the DECSCNM control sequence, just as you would with a real DEC VT.

#DECVT #ECMA48 #T416 #terminal

@RL_Dane @teamtuck

Try inverting the screen and switching between DEC VT520 "light" and "dark". (As you can see, my toolkit has a handy tool for doing this, but it's a simple exercise in printf(1) without.) If that's not satisfactory, then fiddle with the #terminal emulator's palette configuration.

There's nothing that you can do otherwise. In GUIs, applications have "Give me the user's choice of title bar colour" library calls. There's none of that for Unix TUIs.

#T416 #DECVT #ECMA48

@RL_Dane @teamtuck (continued...)

The _only_ control that you have is DECSCNM, an extension to ECMA-48 control sequences from DEC VTs that many terminal emulators (sort of, rxvt getting it wrong, for example) also support.

It basically inverts the sense of the SGR 7 (negative image/reverse video) attribute for the entire display. DEC VT520 doco called it "light" and "dark".

https://vt100.net/docs/vt510-rm/DECSCNM.html

http://jdebp.info/Softwares/nosh/guide/commands/setterm.xml

#DECVT #ECMA48 #T416

@RL_Dane @teamtuck (continued...)
How the ECMA-48, #AIXTerm, and ITU T.416 indexed colours come out is up to the #terminal; as is, indeed, how the default colour comes out.

For these indexed colour schemes there's usually a palette that maps to RGB. Some terminal _emulators_ can adjust the palette. But real terminals didn't even have the 256-colour indexed system, let alone palettes.

The applications pretty much have no say.

#DECVT #ECMA48 #T416
(...continued)

@RL_Dane @teamtuck

The colour #terminal paradigm just doesn't work that way.

Applications can pick from the 8 colours of ECMA-48, or from that plus the additional 8 colours from IBM #AIXterm, or from the 256 indexed colour set of ITU T.416, or from the full ITU T.416 RGB direct colour system.

There are no "modes" or "themes". An application asks for the default colour, or for an explicit ECMA-48, AIXterm, T.416 indexed colour, or RGB direct colour.

#DECVT #ECMA48 #T416
(...continued)