Thinker
A Thinker class is derived from Object, and is used as the base for an Actor and more. Unlike actors, thinkers are not physically present in the game at all.
| Note: This feature is for ZScript only. |
Thinkers are generally used to 'run the game' -- movement, shooting, performing functions, etc.
Thinkers do not possess the many properties and functions an actor has, drastically cutting down on the amount of overhead generated from creating an actor. As such, these make excellent candidates for replacing dummy actors used to monitor and modify primary actors.
To create a new instance of a Thinker, use the following:
new("<your thinker class name>");
Stats
The engine utilizes stat numbers on thinkers to organize thinkers and whether to call their Tick() functions or not.
Some have special use cases such as the STAT_CORPSEPOINTER, invoked by A_QueueCorpse, which creates a thinker for the calling actor, utilizing internal code to eliminate corpses as the queue when filled.
Because of the aforementioned internal handling, take caution when changing a stat number. The engine may manipulate them at any time and cause issues. Thinkers also can only belong to one stat category at any time.
The safest ranges to use are anywhere under 127, and the unmentioned numbers not defined in the list below (i.e. 99, 98, etc -- so long as they are not defined internally).
NOTE: Not all thinkers will actually use their Tick() virtuals based on their stat numbers (see below under the comment 'Thinkers that don't actually think'). It's possible to have another thinker manually call the non-ticking thinker's Tick function inside its own.
Internal Code
class Thinker : Object native play
{
enum EStatnums
{
// Thinkers that don't actually think
STAT_INFO, // An info queue
STAT_DECAL, // A decal
STAT_AUTODECAL, // A decal that can be automatically deleted
STAT_CORPSEPOINTER, // An entry in Hexen's corpse queue
STAT_TRAVELLING, // An actor temporarily travelling to a new map
STAT_STATIC, // persistent across maps.
// Thinkers that do think
STAT_FIRST_THINKING=32,
STAT_SCROLLER=STAT_FIRST_THINKING, // A DScroller thinker
STAT_PLAYER, // A player actor
STAT_BOSSTARGET, // A boss brain target
STAT_LIGHTNING, // The lightning thinker
STAT_DECALTHINKER, // An object that thinks for a decal
STAT_INVENTORY, // An inventory item
STAT_LIGHT, // A sector light effect
STAT_LIGHTTRANSFER, // A sector light transfer. These must be ticked after the light effects.
STAT_EARTHQUAKE, // Earthquake actors
STAT_MAPMARKER, // Map marker actors
STAT_DLIGHT, // Dynamic lights
STAT_USER = 70,
STAT_USER_MAX = 90,
STAT_DEFAULT = 100, // Thinkers go here unless specified otherwise.
STAT_SECTOREFFECT, // All sector effects that cause floor and ceiling movement
STAT_ACTORMOVER, // actor movers
STAT_SCRIPTS, // The ACS thinker. This is to ensure that it can't tick before all actors called PostBeginPlay
STAT_BOT, // Bot thinker
MAX_STATNUM = 127
}
const TICRATE = 35;
native LevelLocals Level;
virtual native void Tick();
virtual native void PostBeginPlay();
native void ChangeStatNum(int stat);
static clearscope int Tics2Seconds(int tics)
{
return int(tics / TICRATE);
}
}