Memory management

Godot classes can be instanced with the engine's memnew template function. Other allocation methods such as D's GC new will not work with Godot classes, since the C++ engine is often responsible for deleting the objects.

After being created with memnew, most Godot objects are managed automatically:

Nodes delete all their child nodes when they are themselves destroyed. Since nodes are usually children of a single large node tree, the SceneTree, it is rarely necessary to manually delete them.
- If the node is not part of the tree or was removed with Node.removeChild, delete it with memdelete.
- To manually delete a node that is still in the tree, call Node.queueFree on it instead of memdelete. This will remove and delete the node only after notifications and signals from the current frame have reached it.
References, including Resources, are reference-counted with the Ref!T wrapper.
- memnew and functions returning References always return them already wrapped in Ref.
- Never manually delete a Reference with memdelete; there may be other references to it elsewhere.
- Only pass around a raw pointer taken from a Ref if you can ensure that at least one Ref to it will exist for as long as the pointer does. This will be enforced with scope in @safe code once DIP1000 is accepted.
- Like Ref, Variant also adds to the ref-count when a Reference is assigned to it.

Examples

class Test : GodotScript!Node
{
	@Method _ready()
	{
		Node a = memnew!Node;
		Node b = memnew!Node;
		a.addChild(b);
		memdelete(a); // MUST manually delete nodes that aren't in the tree
		// deleting the parent `a` also first deletes `b`
		
		Node c = memnew!Node;
		owner.addChild(c); // add `c` to the tree as a child of `this`
		// the tree will delete `c` right before it deletes `this` when the game is exited
		
		Node d = memnew!Node;
		owner.addChild(d);
		d.queueFree(); // remove and delete `d` once notifications and signals are finished being sent to it
		
		Ref!ArrayMesh mesh = memnew!ArrayMesh;
		// Ref will delete `mesh` at end of scope
		
		Ref!Texture tex = ResourceLoader.load("res://icon.png").as!Texture;
		// Ref will delete `tex` only if it isn't already loaded elsewhere.
		
		GodotObject manuallyManaged = memnew!GodotObject;
		memdelete(manuallyManaged); // MUST manually delete plain GodotObjects
	}
}

Memory management

Examples

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