Category:Structure access

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One of the hallmarks of EDuke32's CON scripting advancements is the ability to access many of the game's internal data structures.

Usage

Struct access was designed with the syntax of an array of a struct type in the C programming language.

The index in [square brackets] is an ID number that has different meanings for different structs. Most simple uses of struct access will suffice to use the gamevar THISACTOR as an index, which usually means the current sprite but is also usable as a magic token for different meanings with non-sprite structures. Other times, you may know an ID from a command like findnearactor or espawn (from gamevar RETURN). On occasion you may also loop through all or a selection of ID numbers.

Getters & Setters

Get/set commands are the original methods of CON struct access that date back to DOS EDuke.

get<struct>[<id>].<member> <gamevar>
set<struct>[<id>].<member> <value>

The get commands fetch one of the members of a structure into a gamevar.

The set commands assign the value provided to the member.

<id> can be omitted entirely, which implies an id of THISACTOR.

The commands with the "var" suffix are used to access custom members for a struct, which are really just that ID's gamevars which have the per-<struct> flag set. So setactorvar[THISACTOR].temp 0 is the same as setvar temp 0.

Quick Access

More recently added, structs can be used in place of gamevars, in the form <struct>[<id>].<member>. For example:

ifvarg userdef[].executions 10000
{
    redefinequote 117 You have way too much time on your hands.
    echo 117
}

With quick access, structures are always read-only. Attempting to use a gamevar-writing command on a quick access structure will result in a compiler error.

Quick struct access cannot be used as an index to other quick struct accesses.

Structs

Get/Set Name Quick Name ID type THISACTOR meaning Description Notes
actor sprite sprite id current sprite sprites and hittypes
actorvar sprite id current sprite per-actor gamevars
tspr sprite id current sprite sprites' display properties Can only be used within EVENT_ANIMATESPRITES on sprites with mdflags containing flag 16.
projectile tile number (none) projectile types
thisprojectile sprite id current sprite individual projectiles
sector sector id current sprite's sector sectors, floors, and ceilings
wall wall id (none) walls
player player id current player players
playervar player id current player per-player gamevars
input player id current player input Generally used within EVENT_PROCESSINPUT.
userdef (none) (none) user preferences, game state Use nothing within the brackets.
(none) tiledata tile number (none) art tiles
(none) paldata palookup number (none) palette lookups (palswaps)