GUI Scripting: Parsing of Set 'Cmd'

See GUI Scripting Language for a broader background article.

Implementation Note - When Parsing GUI Commands of Form 'Set "Cmd" '

By Tels

Commands in the main menu GUI with "cmd" as first parameter

set "cmd" "mycommand argument1 argument2;"

are handled in idGameLocal::HandleMainMenuCommands() in game/game_local.cpp.

Original Problem

For each of the parts "mycommand", "argument1", "argument2" and sometimes the final ";", the routine is called again.

One special case is just using "set" "cmd" "mycommand", this will call HandleMainMenuCommands() twice, once with "mycommand" and once with ";" as the menuCommand parameter.

Commands like "play" or "music" are special cases, too, only the first part ("play" or "music") is relayed to the routine, but the argument is not. Thus it seems impossible to recover what sound shader is to be played.

Implemented Solution

The routine therefore predicts how many arguments the current command takes, accumulating them on a stack. And when it has seen enough arguments, handles the command and clears the stack before returning.

Any stray ";" as command is silently skipped.

The routine will also complain if you don't give enough arguments to a command.

Examples

set "cmd" "play sound/meta/menu/mnu_hover";  // will result in "play", and potentially ";"
set "cmd" "log 'Some text here';";           // will result in "log", "Some text here" and ";" - written to the console
set "cmd" "mainmenu_heartbeat";              // will result in "mainmenu_heartbeat" and ";"
set "cmd" "mainmenu_heartbeat;";             // will result in "mainmenu_heartbeat", ";" and ";"

Note: The "log" command only works on MainMenu guis, and only if the executable has been built with the cvar "tdm_debug_mainmenu" set to "1".

See also

• Introduction to Doom3 GUIs
• GUI Scripting on modwiki
• The "set" command on modiwki