SwiftGodotKit provides a way of embedding Godot into an existing Swift application and driving Godot from Swift, without having to use an extension. This is a companion to SwiftGodot which provides the API binding to the Godot API.

Take a look at the TrivialSample here to see how it works.

You will need Swift 5.9 for this (Xcode 15 release candidate will do).

Reference this Package.swift and then you can write a simple program like this:

import Foundation
import SwiftGodot
import SwiftGodotKit

func loadScene (scene: SceneTree) {
    let rootNode = Node3D()
    let camera = Camera3D ()
    camera.current = true
    camera.position = Vector3(x: 0, y: 0, z: 2)
    
    rootNode.addChild(node: camera)
    
    func makeCuteNode (_ pos: Vector3) -> Node {
        let n = SpinningCube()
        n.position = pos
        return n
    }
    rootNode.addChild(node: makeCuteNode(Vector3(x: 1, y: 1, z: 1)))
    rootNode.addChild(node: makeCuteNode(Vector3(x: -1, y: -1, z: -1)))
    rootNode.addChild(node: makeCuteNode(Vector3(x: 0, y: 1, z: 1)))
    scene.root?.addChild(node: rootNode)
}


class SpinningCube: Node3D {
    required init (nativeHandle: UnsafeRawPointer) {
        super.init (nativeHandle: nativeHandle)
    }
    
    required init () {
        super.init ()
        let meshRender = MeshInstance3D()
        meshRender.mesh = BoxMesh()
        addChild(node: meshRender)
    }
    
    override func _input (event: InputEvent) {
        guard event.isPressed () && !event.isEcho () else { return }
        print ("SpinningCube: event: isPressed ")
    }
    
    public override func _process(delta: Double) {
        rotateY(angle: delta)
    }
}

func registerTypes (level: GDExtension.InitializationLevel) {
    switch level {
    case .scene:
        register (type: SpinningCube.self)
    default:
        break
    }
}

runGodot(args: [], initHook: registerTypes, loadScene: loadScene, loadProjectSettings: { settings in })

A standalone sample that you can use as a starting point is available here, when used as SwiftPM:

https://github.com/migueldeicaza/SwiftGodotKit/tree/main/StandaloneExample

Sausage Making Details

If you want to compile your own version of libgodot.framework, follow these instructions

Check out SwiftGodot and SwiftGodotKit as peers as well as a version of Godot suitable to be used as a library:

git clone git@github.com:migueldeicaza/SwiftGodot
git clone git@github.com:migueldeicaza/SwiftGodotKit
git clone git@github.com:migueldeicaza/libgodot

Compile libgodot, this sample shows how I do this myself, but you could have different versions

cd libgodot
scons target=template_debug dev_build=yes library_type=shared_library debug_symbols=yes 

The above will produce the binary that you want, then create an xcframework out of it, using the script in SwiftGodot (a peer to this repository):

cd ../SwiftGodot/scripts
sh -x make-libgodot.xcframework ../../SwiftGodot ../../libgodot /tmp/

Then you can reference that version of the libgodot.xcframework

Details

This relies currently on the LibGodot patch that is currently pending approval:

https://github.com/godotengine/godot/pull/72883

For your convenience, I have packaged the embeddable Godot for Mac as an xcframework so merely taking a dependency on this package should get everything that you need