Test: True color in terminal

[Tyriar]

Test for #18544

Complexity: 3

• mac/Linux @kieferrm
• Windows @sbatten (use WSL in terminal)

The integrated terminal now supports true color (24-bit) rendering, please verify that the colors are working in both the DOM renderer* and canvas renderer:

"terminal.integrated.rendererType": "dom",
"terminal.integrated.rendererType": "canvas",

Print colors in this mode to the terminal uses the CSI Pm m escape sequence where Pm is:

• Pm = 3 8 ; 2 ; Pr ; Pg ; Pb -> Set foreground color to RGB Pr/Pg/Pb.
• Pm = 4 8 ; 2 ; Pr ; Pg ; Pb -> Set background color to RGB Pr/Pg/Pb.

The easiest way to test this is via echo -e:

echo -e '\x1b[38;2;255;0;0mrgb(255, 0, 0) red foreground'
echo -e '\x1b[48;2;0;0;255mrgb(0, 0, 255) blue background'

Experiment with mixing true color with other colors, for example true color foreground and ansi background \x1b[38;2;255;0;0m\x1b[42m. For ANSI color mode use \x1b[3${x}m (fg) and \x1b[4${x}m (bg), for 256 color mode (a fixed palette) use \x1b[38;5;${num}m (fg) and \x1b[48;5;${num}m (bg).

More details/references:

• Search "(SGR)" on https://invisible-island.net/xterm/ctlseqs/ctlseqs.html
• https://gist.github.com/sindresorhus/bed863fb8bedf023b833c88c322e44f9
• https://askubuntu.com/a/821163/409516

* You may run into this issue in the DOM renderer #74183, it will be fixed in tomorrow's build.

[kieferrm]

This works as expected in all variations. CPU consumption when scrolling large colored output goes up to 100% in canvas mode and beyond that in dom mode. Dom mode in general is significantly slower.

[Tyriar]

The slow down is expected for canvas as it only caches the first 16 colors, the webgl renderer caches everything.