PhysicsBody: Could not create physics body - swift

I have an entire working game that has been up on the App Store, but since iOS 13 it simply does not work. I've installed the game onto my device via Xcode and I'm getting a lot of errors coming up saying:
PhysicsBody: Could not create physics body.
I've been creating my SKSpriteNodes like this:
let bird = SKSpriteNode(texture: SKTextureAtlas(named:"player").textureNamed("bird0001"))
bird.physicsBody = SKPhysicsBody(texture: bird.texture!,
size: bird.size)
Based on some research, this is possibly an ongoing bug with iOS and Xcode. Could someone please confirm if this is the case, as this seems to be like a major problem for Games on the app store that create their SKSpriteNodes using textures?
Is there a fix to this where textures are needed?

OK, here's a test of different approaches for avoiding this bug as of iOS 13.3 (edit also now tried on 13.3.1) and Xcode version 11.3. Full source of the test at this link:
https://github.com/bg2b/bugtest
Relevant code:
func addShip(_ texture: SKTexture, how: String) {
let sprite = SKSpriteNode(texture: texture)
sprite.position = CGPoint(x: x, y: 0)
sprite.zRotation = .pi / 4
x += 100
sprite.physicsBody = SKPhysicsBody(texture: texture, size: sprite.size)
if sprite.physicsBody == nil {
print("\(how) failed")
} else {
print("\(how) worked")
}
addChild(sprite)
}
override func didMove(to view: SKView) {
// The atlas version of a texture
addShip(SKTexture(imageNamed: "ship_blue"), how: "simple atlas reference")
// From an atlas, but call size() to force loading
let texture = SKTexture(imageNamed: "ship_blue")
_ = texture.size()
addShip(texture, how: "atlas force load")
// Reconstruct via CGImage (size would be wrong because of 2x)
let cgTexture = SKTexture(cgImage: texture.cgImage())
addShip(cgTexture, how: "reconstruct via cgImage")
// Re-render using view
let renderedTexture = view.texture(from: SKSpriteNode(texture: texture))!
addShip(renderedTexture, how: "re-render using view")
// Non-atlas texture
addShip(SKTexture(imageNamed: "nonatlas_ship_blue"), how: "not in atlas")
}
Summary:
Simply referencing the texture from an atlas and making the physics body may fail
Force-loading the texture by calling size() before making the body fails
Trying to make a new texture by going through cgImage() fails (the image itself is broken, probably related to the same bug)
Rendering to a texture using a view and then making the physics body from that new texture works
Making the physics body from a non-atlas copy of the texture works
Console output from the test program showing what works and what does not:
2020-02-01 06:23:51.872975-0500 bugtest[14399:9898087] PhysicsBody: Could not create physics body.
simple atlas reference failed
2020-02-01 06:23:51.886387-0500 bugtest[14399:9898087] PhysicsBody: Could not create physics body.
atlas force load failed
2020-02-01 06:23:51.913927-0500 bugtest[14399:9898087] PhysicsBody: Could not create physics body.
reconstruct via cgImage failed
re-render using view worked
not in atlas worked
Here's a screen shot showing the effect of the different approaches. You have to look a bit closely, but only the last two have valid physics bodies.

Related

SceneKit: Rotate node but define target angles

EDIT: I have solved the problem and will post the solution in the next couple of days.
I'm building 3D achievements similar to Apple's Activity app.
I've already loaded my 3D model (a scene with a single node), can show it, and can tap on it to apply a rotational force:
#objc func objectTapped(_ gesture: UITapGestureRecognizer) {
let tapLocation = gesture.location(in: scnView)
let hitResults = scnView.hitTest(tapLocation, options: [:])
if let tappedNode = (hitResults.first { $0.node === badgeNode })?.node {
let pos = Float(tapLocation.x) - tappedNode.boundingBox.max.x
let tappedVector = SCNVector4(x: 0, y: pos, z: 0, w: 0.1)
tappedNode.physicsBody?.applyTorque(tappedVector,
asImpulse: true)
}
}
This works fine. Now to the tricky part:
I want the node to rotate until it either shows its front or backside (like in the Activity app), where it then should stop. It should stop naturally, which means it can overshoot a bit and then return.
To describe it with pictures - here I am holding the node in this position...
...and if I let go of the node, it will rotate to show the front side, which includes a little bit of overshooting. This is the ending position:
Since I'm quite new to SceneKit, I have troubles figuring out how to achieve this effect. It seems like I can achieve that by using SceneKit objects like gravity fields, without having to calculate a whole lot of stuff by myself, or at least that's what I'm hoping for.
I don't necessarily ask for a full solution, I basically just need a point in the right direction. Thanks in advance!

SKTextureAtlas gets overridden by declaration of second SKTextureAtlas

Whenever I create and define two variables as type SKTextureAtlas they rewrite each other. Here is my initial creation of my two SKTextureAtlas
class GameScene: SKScene {
var idle = true
var TextureAtlas = SKTextureAtlas()
var TextureAtlasIdle = SKTextureAtlas()
Later on in my code I assign a folder of images to each atlas. If I comment out the second atlas my animation works, but when I define the two as shown below my animation overlaps and plays frames from cat_walk even though it is told to only play cat_idle
TextureAtlasIdle = SKTextureAtlas(named: "cat_idle")
for i in 1...TextureAtlasIdle.textureNames.count{
let Name = "\(i).png"
TextureArrayIdle.append(SKTexture (imageNamed: Name))
}
TextureAtlas = SKTextureAtlas(named: "cat_walk")
This is how I start my cat_idle animation. I don't start the cat_walk animation
aN.run(SKAction.repeatForever(SKAction.animate(with:self.TextureArrayIdle, timePerFrame: 0.1)))
I'm trying to find out why this line of code is causing my two different animations to overlap.
TextureAtlas = SKTextureAtlas(named: "cat_walk")
Texture Atlas is kind of a sprite sheet for your game. Your approach is not right for accessing atlas images for the game. modify your for loop like below:
for i in 0..< 8 {
let texture:SKTexture = TextureAtlasIdle.textureNamed(String(format: "%i", i+1))
TextureArrayIdle.insert(texture, at:i)
}
Every time you access your atlas folder, use this for loop procedure. i have used static 8 number in for loop, it would be your sprites count. There is a simple game called Desert Run in github. please check this out for more clarification.
NB: your cat's images naming must start with 1.png
if you want to run the for loop

ARKit Adding node causes frame drop even after using `prepare`

I am adding a 3D model containing animations to the scene that I previously download from the internet. Before adding this node I use prepare function on it because I wan't to avoid frame drop. But still I get a very short frame drop to about 47 fps. This is caused by executing this prepare function. I also tried using prepare(_:, shouldAbortBlock:) on other dispatch queue, but this still didn't help. Can someone help me resolve this or tell me why there is this happening?
arView.sceneView.prepare([mediaNode]) { [mediaNode, weak self] (success) in
guard let `self` = self else { return }
guard
let currentMediaNode = self.mediaNode as? SCNNode,
currentMediaNode === mediaNode,
!self.mainNode.childNodes.contains(mediaNode)
else { return }
self.mainNode.addChildNode(mediaNode)
}
By the way this is a list of files I'm using to load this model:
https://www.dropbox.com/s/7968fe5wfdcxbyu/Serah-iOS.dae?dl=1
https://www.dropbox.com/s/zqb6b6rxynnvc5e/0001.png?dl=1
https://www.dropbox.com/s/hy9y8qyazkcnvef/0002.tga?dl=1
https://www.dropbox.com/s/fll9jbjud7zjlsq/0004.tga?dl=1
https://www.dropbox.com/s/4niq12mezlvi5oz/0005.png?dl=1
https://www.dropbox.com/s/wikqgd46643327i/0007.png?dl=1
https://www.dropbox.com/s/fioj9bqt90vq70c/0008.tga?dl=1
https://www.dropbox.com/s/4a5jtmccyx413j7/0010.png?dl=1
DAE file is already compiled by Xcode tools so that it can be loaded after being downloaded from the internet. And this is the code I use to load it after it's downloaded:
class func loadModel(fromURL url: URL) -> SCNNode? {
let options = [SCNSceneSource.LoadingOption.animationImportPolicy : SCNSceneSource.AnimationImportPolicy.playRepeatedly]
let sceneSource = SCNSceneSource(url: url, options: options)
let node = sceneSource?.entryWithIdentifier("MDL_Obj", withClass: SCNNode.self)
return node
}
I was experiencing the same issue. My nodes were all taking advantage of physically-based rendering (PBR) and the first time I added a node to the scene, the frame rate dropped significantly, but was fine after that. I could add as many other nodes without a frame rate drop.
I figured out a work around to this issue. What I do is after I create my ARConfiguration and before I call session.run(configuration) I add a test node with PBR to the scene. In order for that node to not appear, I set the node's material's colorBufferWriteMask to an empty array (see this answer: ARKit hide objects behind walls) Then before I add my content I remove that node. Adding and removing this test node does the trick for me.
Here is an example:
var pbrTestNode: SCNNode!
func addPBRTestNode() {
let testGeometrie = SCNBox(width: 0.5, height: 0.5, length: 0.5, chamferRadius: 0)
testGeometrie.materials.first?.diffuse.contents = UIColor.blue
testGeometrie.materials.first?.colorBufferWriteMask = []
testGeometrie.materials.first?.lightingModel = .physicallyBased
pbrTestNode = SCNNode(geometry: testGeometrie)
scene.rootNode.addChildNode(pbrTestNode)
}
func removePBRTestNode() {
pbrTestNode.removeFromParentNode()
}
func startSessionWithPlaneDetection() {
// Create a session configuration
let configuration = ARWorldTrackingConfiguration()
if #available(iOS 11.3, *) {
configuration.planeDetection = [.horizontal, .vertical]
} else {
configuration.planeDetection = .horizontal
}
configuration.isLightEstimationEnabled = true
// this prevents the delay when adding any nodes with PBR later
sceneController.addPBRTestNode()
// Run the view's session
sceneView.session.run(configuration)
}
Call removePBRTestNode() when you add your content to the scene.
Firstly
Get 3D model for AR app with no more than 10K polygons and a texture of 1K x 1K. The best result can be accomplished with 5K...7K polygons per each model. Totally, SceneKit's scene may contain not more than 100K polygons. This recommendation helps you considerably improve rendering performance and, I suppose, you'll have a minimal drop frame.
Secondly
The simplest way to get rid of drop frame in ARKit/SceneKit/AVKit is to use Metal framework. Just imagine: a simple image filter can be more than a hundred times faster to perform on the GPU than an equivalent CPU-based filter. The same things I could say about realtime AV-video and 3D animation – they perform much better on GPU.
For instance, you can read this useful post about using Metal rendering for AVCaptureSession. There's awesome workflow how to use Metal.
P.S. Check your animated object/scene in 3D authoring tool (if it's OK) before writing a code.

Making a node's sprite change as an animation (spriteKit)

im very new to swift, i have made a sprite kit game with a coin sprite. I want to make it spin so ive made 6 sprites in total. Im trying to get a continuous loop of spinning by quickly changing the sprites. I have tried to do this with the code below.
//This will hold all of the coin spinning sprites
let coinTextures : NSMutableArray = []
//There are 6 in total, so loop through and add them
for i in 0..<6 {
let texture : SKTexture = SKTexture(imageNamed: "Coin\(i + 1)")
coinTextures.insert(texture, at: i)
}
//When printing coinTextures, they have all been added
//Define the animation with a wait time of 0.1 seconds, also repeat forever
let coinAnimation = SKAction.repeatForever(SKAction.animate(with: coinTextures as! [SKTexture], timePerFrame: 0.1))
//Get the coin i want to spin and run the action!
SKAction.run(coinAnimation, onChildWithName: "coin1")
As i said im very new so im not sure what ive done wrong here.
Also the name of the coin i want to spin is "coin1" and the sprites so from coin1 to coin 6
You are almost there.
The problem is that your final line creates an action, but not running it on anything...
You got two alternatives:
1) Run your action on your scene
// Create an action that will run on a child
let action = SKAction.run(coinAnimation, onChildWithName: "coin1")
scene?.run(action)
or
2) Run the action directly on the child
// Assuming that you have a reference to coin1
coin1.run(coinAnimation)
As a sidenote, your array could be declared as var coinTextures: [SKTexture] = [], you can use append to add items to it and avoid the casting when you pass the textures to the action.
Or you can use a more compact form to construct your textures array:
let coinTextures = (1...6).map { SKTexture(imageNamed: "Coin\($0)") }
I hope that this makes sense

SpriteKit SKEmitterNode particleAction not working in Xcode 8 / iOS 10

I have an iOS 10 SpriteKit project where I'm trying to put actions on particles from a basic particle emitter created from the "snow" particle template in Xcode 8:
let snowPath = Bundle.main.path(forResource: "Snow", ofType: "sks")!
snowEmitter = NSKeyedUnarchiver.unarchiveObject(withFile: snowPath) as! SKEmitterNode
snowEmitter.position = CGPoint(x: 0, y: size.height / 2)
snowEmitter.particlePositionRange = CGVector(dx: size.width, dy: 0)
snowEmitter.particleAction = SKAction.scale(to: 3, duration: 3)
effectLayer.addChild(snowEmitter) // effectLayer is a SKNode on the scene
The emitter works as it should, but no matter what kind of SKAction I set particleAction to it gets ignored. Has anyone else experienced this?
Update: Doesn't work with Xcode 7 and iOS 9 either.
I think this still might be a leftover iOS 9 bug, not 100% sure. I just tried myself and I cannot get it to work as well.
SKEmitterNode particleAction not working iOS9 Beta
Can you not achieve the same effect using the particles settings directly in snow.sks in the inspector on the right?
You are probably looking at †hose two settings and its subsettings.
1) Particle life cycle (start, range)
2) Particle scale (start, range, speed)
This article has a nice description of each setting.
http://www.techotopia.com/index.php/An_iOS_8_Sprite_Kit_Particle_Emitter_Tutorial#Particle_Birthrate
As a general tip
Your code is not very safe in the first 2 lines because you force unwrapped the snow particle.
If you ever change the name and forget about it or the file becomes corrupted than you will crash. You should change it to something like this
guard let snowPath = Bundle.main.path(forResource: "Snow", ofType: "sks") else { return } // or if let snowPath = ...
snowEmitter = NSKeyedUnarchiver.unarchiveObject(withFile: snowPath) as? SKEmitterNode
...
You can also simply this code a lot by simple saying this where you define your snowEmitter property
let snowEmitter = SKEmitterNode(fileNamed: "Snow")
This will return an optional as well, just like your old code. Than in your method where you set up the emitter say something like this (dont use !)
if let snowEmitter = snowEmitter {
snowEmitter.position =
...
}
Hope this helps
There's another way to achieve the goal.
Make two or more particle systems.
Create two or more noise fields.
Bitmask match one each of the particle systems to one of the noise fields.
Put the noise fields down the bottom, where you want the wiggles to happen
Adjust the noise fields to taste.
As a 2021 datapoint, whilst adding particle emitters to Touchgram, I spent a couple of days exploring this. I came to the conclusion that they were broken in iOS9 and never fixed.