Category:Gamevar manipulation

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Definition

gamevar <varname> <value> <flags>

var <varname> <value> <flags>

A gamevar is a variable that can be used to store numerical data which can then be referenced between actors, states and events. var is hereby semantically equivalent to gamevar.

The gamevar's flags define a bitmap that determines how the variable is treated by the game. For instance, a gamevar with flags of 0 is known as a global variable. A global variable exists once in the code, and any time a global variable is set, the new value is seen by all actors and events. A gamevar with flag bit 1 set is a per-player variable, which exists once for each player in the game. A gamevar with flag bit 2 set is a per-actor variable, which exists as many times in the code as there are sprites in the map. This means that each sprite has its own copy of a per-actor variable stored in memory. Note that a gamevar can only be defined as either global, per-player, or per-actor, but not as a combination thereof.

Gamevars are stored as signed 32-bit integers and therefore have a value range of -2,147,483,648 (-231) to 2,147,483,647 (231-1). Going above and below this range causes the value to overflow and underflow respectively.

Note that it is possible to omit the <value> and <flags> parameters entirely to define a global variable with an initial value of 0, with no other flags set. Example:

var TEMP1

It is also possible to chain flags separately at the end of the gamevar definition, instead of compiling them into a single value, as follows:

var TEMP2 10 1 4096    // This defines a per-player (1), read-only (4096) variable with initial value 10.

The following pages contain information on basic gamevar operations as well as conditional statements:

Flags

The following table shows all currently defined gamevar flags. The first 2 are the only ones needed under normal circumstances, but one can also assign higher flags to user-defined gamevars (given that you know what you are doing).

Exposed Value Label Description
Yes 1 GAMEVAR_PERPLAYER Per-player variable.
Yes 2 GAMEVAR_PERACTOR Per-actor variable.
3 GAMEVAR_USER_MASK Bitmask controlling what flags can be set from con; only flags less than this can.
Internal 8 GAMEVAR_RESET
256 GAMEVAR_FLAG_DEFAULT Allow override (not used).
256 GAMEVAR_DEFAULT Allow override (not used, but always cleared for user-defined gamevars).
512 GAMEVAR_FLAG_SECRET Don't dump...
Yes 1024 GAMEVAR_NODEFAULT Don't reset. Useful if you want a variable to be set once you start the game (otherwise it's reset each time you start a new game).
2048 GAMEVAR_SYSTEM Cannot change mode flags...(only default value)
4096 GAMEVAR_READONLY Values are read-only (no setvar allowed)
8192 GAMEVAR_INT32PTR plValues is a pointer to an int32_t
16384 GAMEVAR_FLAG_SYNCCHECK check event sync when translating
32768 GAMEVAR_INT16PTR plValues is a pointer to a short
Yes 131072 GAMEVAR_NORESET Variable values are not reset when restoring map state
262144 GAMEVAR_SPECIAL Flag for structure member shortcut vars
Yes 524288 GAMEVAR_NOMULTI Don't attach to multiplayer packets
1048576 GAMEVAR_Q16PTR plValues is a pointer to a q16.16
Yes 2097152 GAMEVAR_SERIALIZE Write into permasaves