A successor project is currently underway. Future updates will be made to this project.

This repository may be operated as a mirror of the said project, but this has not been decided yet.

It enable us to work godot-4.x with Nim.

Based on godot-cpp 4.1 stable

• See test/ to get an overview of the binding interface.
• There is a nim implementation of Dodge the Creeps! at demo/.

• Initial loading of the extension fails

  Initialization of the extension fails the first time. Reloading solves the problem.

• AudioStreamPlayer causes a leak in the resources used by this node. We have seen this happen in the demo project.

This project is in the early stages of development and some features are not yet operational.

See GodotSideTester and tester.gd

• Add defined Extension-Class Node into scene
• Instantiate Extension-Class
• Call Extension-Class method
• Use Extension-Class property
• Receive/Emit Extension-Class signal

See NimSideTester

• Define Extension-Class
• Define Simple Extension-Class method
• Define Extension-Class property
• Define/Emit Extension-Class signal
• Instantiate Engine-Class
• Call Engine-Class method (E.g. Node.get_node)
• Override virtual hooks of Engine-Class (E.g. _ready, _process)
• Call Variants' method

• Async Dispatch

• Upgrade to v4.2
• Define utility functions (E.g. print)
• Register user-defined methods
  • Register and call simple method
    • access to self instance
    • access to other arguments
    • return value
  • Support varargs
  • Support static
  • Support virtual
  • Support default-value
• Auto-react to typical notifications
• Define constants
  • Define Variant constants
  • Define Class constants

• Using Parallelism
• Library hot reloading
• GDScript integration
  • Static conversion from GDScript to Nim (c2nim-like converter)
  • GDScript Embedding

• C++ backend
  • Module development

...And so on.

To handle godot's RefCounted, we have defined our own GD_ref type that wraps Nim's ref type. It calls reference/unreference at the appropriate time (copy, destruction, etc.).

let obj1: Engine = Engine.singleton
let obj2: Engine = /Engine

# getNode(Node, NodePath): Node
let obj1: Control = node.getNode("Control") as Control
# `/`(Node, NodePath): Node = getNode(Node, NodePath)
let obj2: Control = node/"Control" as Control
# `/`(Node, typedesc[SomeNode]): SomeNode = getNode(Node, $SomeNode) as SomeNode
let obj3: Control = node/Control

Godot-nim supports GL-like swizzling operator .*.

To use swizzling, please switch -d:nimPreviewDotLikeOps

let v: Vector3 = [0f, 1, 2]
var v_sub = v.*zxz
assert v_sub == [2f, 0, 2]
v_sub.*xy = [3f, 4]
assert v_sub == [3f, 4, 2]
assert not compiles(v_sub.*xz = [5f, 6])

There are four types of accessors: x, y, z, and w.

Immutable values can be obtained in any combination.

let v2 = v.*zxy
let v3 = v.*xxxxxxxxx

Mutable values can only be retrieved by contiguous accessors (i.e., subsets).

v.*xy = [10f, 11]
v.*yz = [12f, 13]
v.*xyz = [14f, 15, 16]

Though if the original value is immutable, sub-vector will be too.

assert not compiles([1, 2, 3].*xy = [10, 11])

Single accessor represents mutable scalar.

let s: float32 = v.*x
v.*x = 20

engine classes and engine variants are generated by generator/.

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