Games/Quake/cvar.h

   1 /*
   2 Copyright (C) 1996-1997 Id Software, Inc.
   3
   4 This program is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU General Public License
   6 as published by the Free Software Foundation; either version 2
   7 of the License, or (at your option) any later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  12
  13 See the GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18
  19 */
  20 // cvar.h
  21
  22 /*
  23
  24 cvar_t variables are used to hold scalar or string variables that can be changed or displayed at the console or prog code as well as accessed directly
  25 in C code.
  26
  27 it is sufficient to initialize a cvar_t with just the first two fields, or
  28 you can add a ,true flag for variables that you want saved to the configuration
  29 file when the game is quit:
  30
  31 cvar_t  r_draworder = {"r_draworder","1"};
  32 cvar_t  scr_screensize = {"screensize","1",true};
  33
  34 Cvars must be registered before use, or they will have a 0 value instead of the float interpretation of the string.  Generally, all cvar_t declarations should be registered in the apropriate init function before any console commands are executed:
  35 Cvar_RegisterVariable (&host_framerate);
  36
  37
  38 C code usually just references a cvar in place:
  39 if ( r_draworder.value )
  40
  41 It could optionally ask for the value to be looked up for a string name:
  42 if (Cvar_VariableValue ("r_draworder"))
  43
  44 Interpreted prog code can access cvars with the cvar(name) or
  45 cvar_set (name, value) internal functions:
  46 teamplay = cvar("teamplay");
  47 cvar_set ("registered", "1");
  48
  49 The user can access cvars from the console in two ways:
  50 r_draworder                     prints the current value
  51 r_draworder 0           sets the current value to 0
  52 Cvars are restricted from having the same names as commands to keep this
  53 interface from being ambiguous.
  54 */
  55
  56 typedef struct cvar_s
  57 {
  58         char    *name;
  59         char    *string;
  60         qboolean archive;               // set to true to cause it to be saved to vars.rc
  61         qboolean server;                // notifies players when changed
  62         float   value;
  63         struct cvar_s *next;
  64 } cvar_t;
  65
  66 void    Cvar_RegisterVariable (cvar_t *variable);
  67 // registers a cvar that allready has the name, string, and optionally the
  68 // archive elements set.
  69
  70 void    Cvar_Set (char *var_name, char *value);
  71 // equivelant to "<name> <variable>" typed at the console
  72
  73 void    Cvar_SetValue (char *var_name, float value);
  74 // expands value to a string and calls Cvar_Set
  75
  76 float   Cvar_VariableValue (char *var_name);
  77 // returns 0 if not defined or non numeric
  78
  79 char    *Cvar_VariableString (char *var_name);
  80 // returns an empty string if not defined
  81
  82 char    *Cvar_CompleteVariable (char *partial);
  83 // attempts to match a partial variable name for command line completion
  84 // returns NULL if nothing fits
  85
  86 qboolean Cvar_Command (void);
  87 // called by Cmd_ExecuteString when Cmd_Argv(0) doesn't match a known
  88 // command.  Returns true if the command was a variable reference that
  89 // was handled. (print or change)
  90
  91 void    Cvar_WriteVariables (FILE *f);
  92 // Writes lines containing "set variable value" for all variables
  93 // with the archive flag set to true.
  94
  95 cvar_t *Cvar_FindVar (char *var_name);
  96
  97 extern cvar_t   *cvar_vars;