I'm getting unexpected results when exporting the contents of a SceneKit scene to a Collada (.dae) file. Here's what I have so far.
I created a simple scene with 5 spheres along the x-axis
var x:CGFloat = 0
for i in 0...4 {
let sphere = SCNNode(geometry: SCNSphere(radius: 1))
sphere.name = "sphere\(i+1)"
sphere.position = SCNVector3(x: x, y: 0, z: 0)
exportScene.rootNode.addChildNode(sphere)
x += 2
}
and exported the contents with
let url = URL(fileURLWithPath: pathName)
exportScene.write(to: url, options: nil, delegate: nil) { totalProgress, error, stop in
print("Export progress: \(totalProgress * 100.0)%")
}
When I load the .dae file into a 3D program (Cheetah 3D), I expect to have 5 identical spheres along the x-axis but instead the following appears. I had similar issues exporting to a .obj file.
The answer in the following says "Keep in mind that DAE doesn't handle all features of SceneKit, though" but the doesn't go into the limitations of the file format.
Easiest method to export a SceneKit scene as a Collada .dae file?
Q: Does anyone know how to export the contents of a SceneKit scene?
macOS app
Looks like the beginning of SceneKit's sunset.
Neither .dae nor .obj formats are properly generated in SceneKit macOS app. Moreover, an .usdz format is not exported at all.
iOS app
In iOS app, only the .usdz format is exported correctly (it kept all nodes' transforms and names of the SCN scene). This .usdz can be opened in Maya. But .dae and .obj files contain only one sphere instead of five.
If you have problems with USDZ's textures in Maya, read this post please.
Note that .usdz is not exported correctly when using for-in loop.
import SceneKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let sceneView = self.view as! SCNView
sceneView.backgroundColor = .black
sceneView.scene = SCNScene()
let url = URL(string: "file:///Users/swift/Desktop/model.usdz")!
let sphere1 = SCNNode(geometry: SCNSphere(radius: 0.5))
sphere1.position = SCNVector3(x: -2, y: 0, z: 0)
sceneView.scene!.rootNode.addChildNode(sphere1)
// ...sphere2, sphere3, sphere4...
let sphere5 = SCNNode(geometry: SCNSphere(radius: 0.5))
sphere5.position = SCNVector3(x: 2, y: 0, z: 0)
sceneView.scene!.rootNode.addChildNode(sphere5)
DispatchQueue.main.asyncAfter(deadline: .now() + 1) {
sceneView.scene?.write(to: url, delegate: nil) { (prgs, _, _) in
print("Export progress: \(prgs * 100.0)%")
}
}
}
}
P. S.
Tested it on macOS 13.0 Ventura, Xcode 14.1, iOS 16.1 Simulator.
Related
Usually I instantiate SCNParticleSystems by using the file initializer like this:
var stars = SCNParticleSystem(named: "Stars.sncp", inDirectory: nil)
However this project requires a Swift Playground and when I try to use that init function with systems stored in the playground's Resources folder it returns nil (even if I change the specified directory to "Resources" or "/Resources" etc. etc. ).
Are Playground resource paths handled differently to normal apps or am I making a really stupid filenaming mistake?
In Xcode 11 and later there's no preconfigured .scnp Particle System file. Instead you can use Particle System object coming directly from Xcode library.
Or, as always, you can create a particle system in Xcode Playground programmatically.
About Swift Playgrounds for iPad read here.
Here's a code:
import PlaygroundSupport
import SceneKit
let rectangle = CGRect(x: 0, y: 0, width: 1000, height: 200)
var sceneView = SCNView(frame: rectangle)
var scene = SCNScene()
sceneView.scene = scene
sceneView.backgroundColor = .black
let cameraNode = SCNNode()
cameraNode.camera = SCNCamera()
cameraNode.position.z = 70
sceneView.scene!.rootNode.addChildNode(cameraNode)
let particleSystem = SCNParticleSystem()
particleSystem.birthRate = 500
particleSystem.particleLifeSpan = 0.5
particleSystem.particleColor = .systemIndigo
particleSystem.speedFactor = 7
particleSystem.emittingDirection = SCNVector3(1,1,1)
particleSystem.emitterShape = .some(SCNSphere(radius: 15))
let particlesNode = SCNNode()
particlesNode.scale = SCNVector3(2,2,2)
particlesNode.addParticleSystem(particleSystem)
sceneView.scene!.rootNode.addChildNode(particlesNode)
PlaygroundPage.current.liveView = sceneView
I think you're doing a mistake in filename extension. It is .scnp and not .sncp.
Either try without any extension -
var stars = SCNParticleSystem(named: "Stars", inDirectory: nil)
or try with correct extension -
var stars = SCNParticleSystem(named: "Stars.scnp", inDirectory: nil)
Ok, I am working with ARKit and SceneKit here and I am having trouble looking at the other questions dealing with just SceneKit trying to have a model in .dae format and load in various animations to have that model run - now that we're in iOS11 seems that some solutions don't work.
Here is how I get my model - from a base .dae scene where no animations are applied. I am importing these with Maya -
var modelScene = SCNScene(named: "art.scnassets/ryderFinal3.dae")!
if let d = modelScene.rootNode.childNodes.first {
theDude.node = d
theDude.setupNode()
}
Then in Dude class:
func setupNode() {
node.scale = SCNVector3(x: modifier, y: modifier, z: modifier)
center(node: node)
}
the scaling and centering of axes is needing because my model was just not at the origin. That worked. Then now with a different scene called "Idle.dae" I try to load in an animation to later run on the model:
func animationFromSceneNamed(path: String) -> CAAnimation? {
let scene = SCNScene(named: path)
var animation:CAAnimation?
scene?.rootNode.enumerateChildNodes({ child, stop in
if let animKey = child.animationKeys.first {
animation = child.animation(forKey: animKey)
stop.pointee = true
}
})
return animation
}
I was going to do this for all my animations scenes that I import into Xcode and store all the animations in
var animations = [CAAnimation]()
First Xcode says animation(forKey: is deprecated and This does not work it seems to (from what I can tell) de-center and de-scale my model back to the huge size it was. It screws up its position because I expect making the model move in an animation, for example, would make the instantiated model in my game snap to that same position.
and other attempts cause crashes. I am very new to scene kit and trying to get a grip on how to properly animate a .dae model that I instantiate anywhere in the scene -
How in iOS11 does one load in an array of animations to apply to their SCNNode?
How do you make it so those animations are run on the model WHEREVER THE MODEL IS (not snapping it to some other position)?
At first I should confirm that CoreAnimation framework and some of its methods like animation(forKey:) instance method are really deprecated in iOS and macOS. But some parts of CoreAnimation framework are now implemented into SceneKit and other modules. In iOS 11+ and macOS 10.13+ you can use SCNAnimation class:
let animation = CAAnimation(scnAnimation: SCNAnimation)
and here SCNAnimation class has three useful initializers:
SCNAnimation(caAnimation: CAAnimation)
SCNAnimation(contentsOf: URL)
SCNAnimation(named: String)
In addition I should add that you can use not only animations baked in .dae file format, but also in .abc, .scn and .usdz.
Also, you can use SCNSceneSource class (iOS 8+ and macOS 10.8+) to examine the contents of a SCNScene file or to selectively extract certain elements of a scene without keeping the entire scene and all the assets it contains.
Here's how a code with implemented SCNSceneSource might look like:
#IBOutlet var sceneView: ARSCNView!
var animations = [String: CAAnimation]()
var idle: Bool = true
override func viewDidLoad() {
super.viewDidLoad()
sceneView.delegate = self
let scene = SCNScene()
sceneView.scene = scene
loadMultipleAnimations()
}
func loadMultipleAnimations() {
let idleScene = SCNScene(named: "art.scnassets/model.dae")!
let node = SCNNode()
for child in idleScene.rootNode.childNodes {
node.addChildNode(child)
}
node.position = SCNVector3(0, 0, -5)
node.scale = SCNVector3(0.45, 0.45, 0.45)
sceneView.scene.rootNode.addChildNode(node)
loadAnimation(withKey: "walking",
sceneName: "art.scnassets/walk_straight",
animationIdentifier: "walk_version02")
}
...
func loadAnimation(withKey: String, sceneName: String, animationIdentifier: String) {
let sceneURL = Bundle.main.url(forResource: sceneName, withExtension: "dae")
let sceneSource = SCNSceneSource(url: sceneURL!, options: nil)
if let animationObj = sceneSource?.entryWithIdentifier(animationIdentifier,
withClass: CAAnimation.self) {
animationObj.repeatCount = 1
animationObj.fadeInDuration = CGFloat(1)
animationObj.fadeOutDuration = CGFloat(0.5)
animations[withKey] = animationObj
}
}
...
func playAnimation(key: String) {
sceneView.scene.rootNode.addAnimation(animations[key]!, forKey: key)
}
i have imported my collada file of a 3d tunnel in xcode.
2.when i run my sample project it shows 3d tunnel very far and small
class GameViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// create a new scene
let scene = SCNScene(named: "art.scnassets/tube.dae")!
// create and add a camera to the scene
let cameraNode = SCNNode()
cameraNode.camera = SCNCamera()
scene.rootNode.addChildNode(cameraNode)
// place the camera
cameraNode.position = SCNVector3(x: 0, y: 0, z: 15)
// create and add a light to the scene
let lightNode = SCNNode()
lightNode.light = SCNLight()
lightNode.light!.type = SCNLightTypeOmni
lightNode.position = SCNVector3(x: 0, y: 10, z: 10)
scene.rootNode.addChildNode(lightNode)
i just import my collada 3d object in xcode default ship code what should i do to see my 3d tunnel near to the scene as in following pics
in Blender:
when i run SceneKit project the tunnel in simulator looks like this:
[2
5.How can i get my 3d tunnel same view in scenekit as it is in blender.
Does your Collada file already have a camera in it, i.e. the one you're using to produce the first rendering?
If so, locate that camera/node (childNodeWithName). Assign it as your view's point of view. Don't create a new camera in your code.
Or, if you really need to create a new camera, put it at the same location as the point of view used for the first rendering.
I'm creating a game where the player can control a cube.
He could buy new cubes.
I created the basic cube like that :
// MAIN CUBE
mainCubeGeometry = SCNBox(width: 0.2, height: 0.2, length: 0.2, chamferRadius: 0.0)
mainCubeGeometry.firstMaterial?.diffuse.contents = UIColor.redColor()
mainCubeNode = SCNNode(geometry: mainCubeGeometry)
mainCubeNode.position = SCNVector3(x: 0.0, y: 0.0, z: 0.0)
scene.rootNode.addChildNode(mainCubeNode)
I would like to know how use 3D models (dae) of cubes created on any software (SketchUp per exemple). I don't really understand how to load the 3D file when the scene is created (scene = SCNScene(named: "3d.scnassets/cube.dae")) because it is a scene, so it import a scene into my original scene, while I just want to import a 3D model in a node to use it like my basic cube.
Thanks for your help !
SCNScene(named:) returns an SCNNode with all of the objects from that DAE file as child nodes. Load the file, retrieve the bodies you're interested in, and add them to your scene's root node.
Here are a couple of snippets from the Fox sample app from WWDC 2015. The Character class has a node property initialized like this:
let characterScene = SCNScene(named: "game.scnassets/panda.scn")!
let characterTopLevelNode = characterScene.rootNode.childNodes[0]
node.addChildNode(characterTopLevelNode)
And then add the character to the scene like this:
// Add the character to the scene.
scene.rootNode.addChildNode(character.node)
SOLUTION
I found a solution on this post : How do you load a .dae file into an SCNNode in IOS SceneKit?
class func collada2SCNNode(filepath:String) -> SCNNode {
var node = SCNNode()
let scene = SCNScene(named: filepath)
var nodeArray = scene!.rootNode.childNodes
for childNode in nodeArray {
node.addChildNode(childNode as SCNNode)
}
return node
}
Use :
let myNode = collada2SCNNode("nodes.scnassets/node.dae")
scene.rootNode.addChildNode(myNode)
I've just picking up Swift and playing around with SceneKit. I created a simple "Smoke.scnp" particle emitter in the xcode 6 editor, and I'm trying to load that using the SCNParticleSystem class. I have included the SceneKit frame work with the project. When running without the particle system, I could load the camera and other nodes just fine, but including the particle system failed during linking time. The error I got was symbol not found for SCNParticleSystem.
I don't have much experience with SceneKit, so this may not be something specific to xcode6 or Swift. Just wondering if I have to set up anything else?
Below is the snippet of my code:
import SceneKit
import QuartzCore
class GameViewController: NSViewController {
#IBOutlet var gameView: GameView
override func awakeFromNib(){
// create a new scene
let scene = SCNScene()
// Add camera to scene
let cameraNode = SCNNode()
cameraNode.camera = SCNCamera()
scene.rootNode.addChildNode(cameraNode)
// Place camera
cameraNode.position = SCNVector3(x: 0, y: 0, z: 2)
// Add particle emitter
let bgSmokeNode = SCNNode()
var particleSystem = SCNParticleSystem(named: "Smoke", inDirectory: "")
bgSmokeNode.addParticleSystem(particleSystem)
scene.rootNode.addChildNode(bgSmokeNode)
}
}