La classe Variant

À propos

Le type Variant est le plus important de Godot, la classe la plus importante dans le moteur. Un Variant prend seulement 20bytes en mémoire et peut stocker presque tous les types du moteur. Les Variants sont rarement utilisé pour stocker des informations sur une longue période de temps, à la place ils sont utilisés principalement pour la communication, l’édition, la sérialisation et plus générelement déplacer des données.

Un Variant peu :

  • Store almost any datatype
  • Perform operations between many variants (GDScript uses Variant as its atomic/native datatype).
  • Be hashed, so it can be compared quickly to other variants
  • Be used to convert safely between datatypes
  • Be used to abstract calling methods and their arguments (Godot exports all its functions through variants)
  • Be used to defer calls or move data between threads.
  • Be serialized as binary and stored to disk, or transferred via network.
  • Be serialized to text and use it for printing values and editable settings.
  • Work as an exported property, so the editor can edit it universally.
  • Be used for dictionaries, arrays, parsers, etc.

Basically, thanks to the Variant class, writing Godot itself was a much, much easier task, as it allows for highly dynamic constructs not common of C++ with little effort. Become a friend of Variant today.

Références :

Containers: Dictionary and Array

Both are implemented using variants. A Dictionary can match any datatype used as key to any other datatype. An Array just holds an array of Variants. Of course, a Variant can also hold a Dictionary and an Array inside, making it even more flexible.

Modifications to a container will modify all references to it. A Mutex should be created to lock it if multi threaded access is desired.

Copy-on-write (COW) mode support for containers was dropped with Godot 3.0.