How to use 8 bit mode with NoVNC

Question

I've got NoVNC running on Centos 6, and I can connect to it from my web browser without any problems. From some locations the connection is a bit slow, and I'd like to be able to drop back to 8 bit color mode from full color mode. But when I deselect true color from the NoVNC options menu, I get a message saying:

Tight protocol handler only implements true color mode

I have worked around this by commenting out TIGHT from the encodings array in rfb.js, like so:

encodings      = [
    ['COPYRECT',         0x01 ],
    //['TIGHT',            0x07 ],
    ['TIGHT_PNG',        -260 ],
    ['HEXTILE',          0x05 ],
    ['RRE',              0x02 ],
    ['RAW',              0x00 ],
    ['DesktopSize',      -223 ],
    ['Cursor',           -239 ],

This will let the NoVNC client fall back to HEXTILE, which will allow non-true color mode. But is there some less hacky way to fall back to 8 bit color mode with NoVNC?

Answer 1

I just pushed a fix that will fall-back to hextile if true color is disabled: https://github.com/kanaka/noVNC/commit/c95456c0e136109447017a43c1cfc5f9ca363b6b

However, note that this probably isn't what you want. 8-bit hextile takes more bandwidth than 24-bit true color tight encoding and my guess is that it will also generally render slower.

The least hacky approach is for somebody to implement 8-bit colour mapped mode for the tight encoding in noVNC. Unfortunately, I don't have time to attack this. Any takes?