Xterm Truecolor  
TRUECOLOR
• About
• Codes
• RGB Values
• Support
• Detection
• Links

ANSI
256COLOR
TRUECOLOR
VT100
XTERM
MUDhalla is a website dedicated to multiplayer text adventure games, also known as MUDs.
Support for 24 bit truecolor was added to xterm in September 2012 by its maintainer Thomas Dickey. It's an extension to the ANSI color standard using a compatible format and has been adopted by several terminal emulators.
To send a truecolor foreground color one must print "\e[38;2;R;G;Bm" where R, G and B contain numbers between 0 and 255 for the corresponding red, green, and blue color intensities. For background colors use 48 instead of 38. To print text in orange (#FF7700) one would use "\e[38;2;255;127;0m".

Truecolor Codes

Truecolor Escape Sequences

Code Effect Note
\e [ CSI Control Sequence Indicator
CSI n m ANSICOLOR ANSI color code (Select Graphic Rendition)
CSI 38 ; 5 ; n m 256COLOR Foreground 8 bit 256 color code
CSI 48 ; 5 ; n m 256COLOR Background 8 bit 256 color code
CSI 38 ; 2 ; r ; g ; b m TRUECOLOR Foreground 24 bit rgb color code
CSI 48 ; 2 ; r ; g ; b m TRUECOLOR Background 24 bit rgb color code

Truecolor RGB Values

Truecolor codes should be displayed as 24 bit RGB colors, similar to 24 bit HTML hexadecimal codes. Unlike 256 colors the displaying of truecolors should be platform independent.

Support
Truecolor support is available in most terminal emulators as of 2018. Support in MUD clients is virtually non-existent as of 2018.
WinTin++ - support as of version 2.01.5

Detection
There is no universal standard for the detection or negotiation of truecolor support. The following methods exist:
By using the TTYPE TELNET option and checking for a terminal emulator or mud client known to support truecolors, such as xterm.
By using the TTYPE TELNET option and checking for the -truecolor suffix. For example: xterm-truecolor.
By using the TTYPE TELNET option and using the MUD Terminal Type Standard to detect truecolor support.

Links

If you want a link added, you can email me at mudclient@gmail.com.

Clients supporting truecolor
True Colour support page - XVilka maintains a list of terminal emulators and applications with truecolor support.

Codebases

Snippets