sv_rollangle

sv_rollangle is a console variable available in all Source games. This float cvar adjusts or disable view rolling (which is used in Black Mesa, and works similarly to Quake and Half-Life).

Note:This console variable is flagged as "launcher"-only in all Source games since Source 2007, so it can be only changed through launch options.

Important:When changing the value through launch options, the console may show Unknown command "sv_rollangle". However the value does actually changes.

Alternatively, you can also use SourceMod or VScript:

sm_cvar sv_rollangle <value> command (with SourceMod installed) or
script Convars.SetValue("sv_rollangle", "<value>") (using VScript).

Note: Black Mesa replaced this command with rollangle.

Confirm:This is confirmed on 2012 mod version, needs confirm on latest Steam version aswell.