This page is for the Source Engine port. For the original, see Half-Life. For the unofficial Source Engine remake, see Black Mesa.
Set Launch Options...
Add the following to <path-to-game>/valve/userconfig.cfg. Create the file as a plain text file if it does not already exist. Adjust keys as desired.
bind SHIFT +holdrun
alias +holdrun -speed
alias -holdrun +speed
alias "runon" "-speed;alias togglerun runoff"
alias "runoff" "+speed;alias togglerun runon"
bind CAPSLOCK togglerun
The glitches seem to have been introduced by a batch of updates in late 2013. An official fix is unlikely at this point, but disabling multicore rendering in the advanced video options seems to work.
Enable developer console (~)