I'm trying to figure out how to optimize my game. I have a lot of turrets etc shooting out physics bodies. The game is playable but can dip into 50 or 45 fps. I've figured out that it is related to adding objects to my scene on the fly.
for example. when my turret is shooting it runs this code
func shootBlaster(){
let blaster = Projectile(color: SKColor.cyanColor(), size: CGSize(width: convertNum(3), height: convertNum(3)))
blaster.name = "blaster"
blaster.physicsBody = SKPhysicsBody(rectangleOfSize: blaster.size)
blaster.physicsBody!.categoryBitMask = CategoryEnemyProjectile
blaster.physicsBody!.contactTestBitMask = CategoryShip | CategoryShipShield
blaster.physicsBody!.collisionBitMask = 0
let fireAction = SKAction.runBlock({
let angle = self.turret.base.zRotation + self.zRotation
let velocity = CGPoint(angle: angle) * convertNum(420)
let vector = CGVectorMake(velocity.x, velocity.y)
let blas = blaster.copy() as Projectile
blas.wpnDmg = 10
blas.position = self.gameScene.gameLayer.convertPoint(self.turret.barrelPos, fromNode: self.turret.base)
self.gameScene.gameLayer.addChild(blas)
blas.physicsBody!.velocity = vector
blas.zRotation = blas.physicsBody!.velocity.angle
blas.runAction(SKAction.removeFromParentAfterDelay(1))
})
let recoilAction = SKAction.moveByX(-5, y: 0, duration: 0.08)
let reverseRecoil = recoilAction.reversedAction()
self.turret.barrel.runAction(SKAction.repeatAction(
SKAction.sequence([
recoilAction,
fireAction,
reverseRecoil
])
,count: self.blasterNum))
}
you can see that I'm adding a "blaster" inside of each of the fireAction blocks. I've noticed games with better performance are rarely adding children at runtime. It seems best to have everything pre-loaded. It makes sense that loading resources during runtime would put a strain on things, but what is the alternative? Do I need to add everything to the scene ahead of time and somehow hide and show it?
With any kind of shooting game where you have numerous projectiles you want to utilize "pooling". Create a pool of projectiles and reuse them as opposed to creating new ones when you need them.
Related
I'm using SpriteKit particle emitter nodes for snow:
let snowEmitterNode = SKEmitterNode(fileNamed: "Snow.sks")
guard let snowEmitterNode = snowEmitterNode else { return }
snowEmitterNode.particleSize = CGSize(width: 4, height: 4)
snowEmitterNode.particleLifetime = 10
snowEmitterNode.particleBirthRate = 10
snowEmitterNode.xAcceleration = -gameSpeed
snowEmitterNode.particleLifetimeRange = 10
snowEmitterNode.position = CGPoint(x: (self.size.width/2), y: 800)
snowEmitterNode.zPosition = 80
addChild(snowEmitterNode)
It looks great, but it only begins once the scene loads, which means there is no snow at the start, and then it all suddenly starts to fall, which obviously looks very fake. Is it possible to somehow set the state of it to have already fallen partly on scene load to avoid this?
It is.
Use the advanceSimulationTime(_:) method to advance the emission of particles by the number of seconds you specify.
E.g. snowEmitterNode.advanceSimulationTime(5)
See https://developer.apple.com/documentation/spritekit/skemitternode/1398027-advancesimulationtime for details
I am making a game in Swift using spritekit and I want 2 objects on screen, one that I move with the touchesMoved function (player) and the other to stay still in its position in the screen (cell).
I wanted to make the objects physicsbody's so that I could work out collisions between them, but now whenever the scene loads the objects fall straight away. And the object moved through touch falls as soon as the user stops touching the screen.
Here's all of the code relating to the object that should stay stationary in the scene and I am unsure what makes it fall.
//Defining the cell
let cell = SKSpriteNode(imageNamed: "cell.png")
override func didMove(to view: SKView){
self.physicsWorld.contactDelegate = self
cell.physicsBody?.categoryBitMask = cellCategory
cell.physicsBody?.contactTestBitMask = playerCategory
cell.physicsBody?.isDynamic = true
cell.physicsBody = SKPhysicsBody(rectangleOf: cell.frame.size)
//Adding the cell to the scene
cell.position = CGPoint(x:size.width * 0.9, y:size.height * 0.9)
cell.size = CGSize(width: 50, height: 50)
addChild(cell)
Any help in what makes the object fall and how I can stop it from happening would be greatly appreciated.
Gravity is by default on. You can either turn it off entirely by setting the gravity property of the scene's physicsWorld:
// somewhere in the scene's initialization, or in didMove if you like
physicsWorld.gravity = CGVector(dx: 0.0, dy: 0.0)
See https://developer.apple.com/documentation/spritekit/skphysicsworld for info on that.
Or you can turn off whether individual objects are affected by gravity. E.g.,
let body = SKPhysicsBody(circleOfRadius: 10.0)
body.affectedByGravity = false
See https://developer.apple.com/documentation/spritekit/skphysicsbody, and in particular, https://developer.apple.com/documentation/spritekit/skphysicsbody/1519774-affectedbygravity
You have a different problem in that you're setting the properties of your cell's physics body before you're creating it. cell.physicsBody?... = will not assign anything until cell.physicsBody exists. So those assignments must be moved after you create cell.physicsBody = SKPhysicsBody(rectangleOf: ...)
I want to create a particle system on iOS using sprite kit where I define the colour of each individual particle. As far as I can tell this isn't possible with the existing SKEmitterNode.
It seems that best I can do is specify general behaviour. Is there any way I can specify the starting colour and position of each particle?
This can give you a basic idea what I was meant in my comments. But keep in mind that it is untested and I am not sure how it will behave if frame rate drops occur.
This example creates 5 particles per second, add them sequentially (in counterclockwise direction) along the perimeter of a given circle. Each particle will have different predefined color. You can play with Settings struct properties to change the particle spawning speed or to increase or decrease number of particles to emit.
Pretty much everything is commented, so I guess you will be fine:
Swift 2
import SpriteKit
struct Settings {
static var numberOfParticles = 30
static var particleBirthRate:CGFloat = 5 //Means 5 particles per second, 0.2 means one particle in 5 seconds etc.
}
class GameScene: SKScene {
var positions = [CGPoint]()
var colors = [SKColor]()
var emitterNode:SKEmitterNode?
var currentPosition = 0
override func didMoveToView(view: SKView) {
backgroundColor = .blackColor()
emitterNode = SKEmitterNode(fileNamed: "rain.sks")
if let emitter = emitterNode {
emitter.position = CGPoint(x: CGRectGetMidX(frame), y: CGRectGetMidY(frame))
emitter.particleBirthRate = Settings.particleBirthRate
addChild(emitter)
let radius = 50.0
let center = CGPointZero
for var i = 0; i <= Settings.numberOfParticles; i++ {
//Randomize color
colors.append(SKColor(red: 0.78, green: CGFloat(i*8)/255.0, blue: 0.38, alpha: 1))
//Create some points on a perimeter of a given circle (radius = 40)
let angle = Double(i) * 2.0 * M_PI / Double(Settings.numberOfParticles)
let x = radius * cos(angle)
let y = radius * sin(angle)
let currentParticlePosition = CGPointMake(CGFloat(x) + center.x, CGFloat(y) + center.y)
positions.append(currentParticlePosition)
if i == 1 {
/*
Set start position for the first particle.
particlePosition is starting position for each particle in the emitter's coordinate space. Defaults to (0.0, 0,0).
*/
emitter.particlePosition = positions[0]
emitter.particleColor = colors[0]
self.currentPosition++
}
}
// Added just for debugging purposes to show positions for every particle.
for particlePosition in positions {
let sprite = SKSpriteNode(color: SKColor.orangeColor(), size: CGSize(width: 1, height: 1))
sprite.position = convertPoint(particlePosition, fromNode:emitter)
sprite.zPosition = 2
addChild(sprite)
}
let block = SKAction.runBlock({
// Prevent strong reference cycles.
[unowned self] in
if self.currentPosition < self.positions.count {
// Set color for the next particle
emitter.particleColor = self.colors[self.currentPosition]
// Set position for the next particle. Keep in mind that particlePosition is a point in the emitter's coordinate space.
emitter.particlePosition = self.positions[self.currentPosition++]
}else {
//Stop the action
self.removeActionForKey("emitting")
emitter.particleBirthRate = 0
}
})
// particleBirthRate is a rate at which new particles are generated, in particles per second. Defaults to 0.0.
let rate = NSTimeInterval(CGFloat(1.0) / Settings.particleBirthRate)
let sequence = SKAction.sequence([SKAction.waitForDuration(rate), block])
let repeatAction = SKAction.repeatActionForever(sequence)
runAction(repeatAction, withKey: "emitting")
}
}
}
Swift 3.1
import SpriteKit
struct Settings {
static var numberOfParticles = 30
static var particleBirthRate:CGFloat = 5 //Means 5 particles per second, 0.2 means one particle in 5 seconds etc.
}
class GameScene: SKScene {
var positions = [CGPoint]()
var colors = [SKColor]()
var emitterNode: SKEmitterNode?
var currentPosition = 0
override func didMove(to view: SKView) {
backgroundColor = SKColor.black
emitterNode = SKEmitterNode(fileNamed: "rain.sks")
if let emitter = emitterNode {
emitter.position = CGPoint(x: frame.midX, y: frame.midY)
emitter.particleBirthRate = Settings.particleBirthRate
addChild(emitter)
let radius = 50.0
let center = CGPoint.zero
for var i in 0...Settings.numberOfParticles {
//Randomize color
colors.append(SKColor(red: 0.78, green: CGFloat(i * 8) / 255.0, blue: 0.38, alpha: 1))
//Create some points on a perimeter of a given circle (radius = 40)
let angle = Double(i) * 2.0 * Double.pi / Double(Settings.numberOfParticles)
let x = radius * cos(angle)
let y = radius * sin(angle)
let currentParticlePosition = CGPoint.init(x: CGFloat(x) + center.x, y: CGFloat(y) + center.y)
positions.append(currentParticlePosition)
if i == 1 {
/*
Set start position for the first particle.
particlePosition is starting position for each particle in the emitter's coordinate space. Defaults to (0.0, 0,0).
*/
emitter.particlePosition = positions[0]
emitter.particleColor = colors[0]
self.currentPosition += 1
}
}
// Added just for debugging purposes to show positions for every particle.
for particlePosition in positions {
let sprite = SKSpriteNode(color: SKColor.orange, size: CGSize(width: 1, height: 1))
sprite.position = convert(particlePosition, from: emitter)
sprite.zPosition = 2
addChild(sprite)
}
let block = SKAction.run({
// Prevent strong reference cycles.
[unowned self] in
if self.currentPosition < self.positions.count {
// Set color for the next particle
emitter.particleColor = self.colors[self.currentPosition]
// Set position for the next particle. Keep in mind that particlePosition is a point in the emitter's coordinate space.
emitter.particlePosition = self.positions[self.currentPosition]
self.currentPosition += 1
} else {
//Stop the action
self.removeAction(forKey: "emitting")
emitter.particleBirthRate = 0
}
})
// particleBirthRate is a rate at which new particles are generated, in particles per second. Defaults to 0.0.
let rate = TimeInterval(CGFloat(1.0) / Settings.particleBirthRate)
let sequence = SKAction.sequence([SKAction.wait(forDuration: rate), block])
let repeatAction = SKAction.repeatForever(sequence)
run(repeatAction, withKey: "emitting")
}
}
}
Orange dots are added just for debugging purposes and you can remove that part if you like.
Personally I would say that you are overthinking this, but I might be wrong because there is no clear description of what you are trying to make and how to use it. Keep in mind that SpriteKit can render a bunch of sprites in a single draw call in very performant way. Same goes with SKEmitterNode if used sparingly. Also, don't underestimate SKEmitterNode... It is very configurable actually.
Here is the setup of Particle Emitter Editor:
Anyways, here is the final result:
Note that nodes count comes from an orange SKSpriteNodes used for debugging. If you remove them, you will see that there is only one node added to the scene (emitter node).
What you want is completely possible, probably even in real time. Unfortunately to do such a thing the way you describe with moving particles as being a particle for each pixel would be best done with a pixel shader. I don't know of a clean method that would allow you to draw on top of the scene with a pixel shader otherwise all you would need is a pixel shader that takes the pixels and moves them out from the center. I personally wouldn't try to do this unless I built the game with my own custom game engine in place of spritekit.
That being said I'm not sure a pixel per pixel diffusion is the best thing in most cases. Expecially if you have cartoony art. Many popular games will actually make sprites for fragments of the object they expect to shader. So like if it's an airplane you might have a sprite for the wings with perhaps even wires hanging out of this. Then when it is time to shatter the plane, remove it from the scene and replace the area with the pieces in the same shape of the plane... Sorta like a puzzle. This will likely take some tweaking. Then you can add skphysicsbodies to all of these pieces and have a force push them out in all directions. Also this doesn't mean that each pixel gets a node. I would suggest creatively breaking it into under 10 pieces.
And as whirlwind said you could all ways get things looking "like" it actually disintegrated by using an emitter node. Just make the spawn area bigger and try to emulate the color as much as possible. To make the ship dissappear you could do a fade perhaps? Or Mabye an explosion sprite over it? Often with real time special effects and physics, or with vfx it is more about making it look like reality then actually simulating reality. Sometimes you have to use trickery to get things to look good and run real-time.
If you want to see how this might look I would recommend looking at games like jetpac joyride.
Good luck!
On some iOS devices (iPhone 6s Plus) there is a partial and arbitrary disappearance of object parts.
How to avoid this?
All sticks must be the same and are clones of one SCNNode.
16 complex SCNNodes, from 3 SCNNode: box, ball and stick. Node containing a geometry by node.flattenedClone().
It must be like this:
Сode fragment:
func initBox()
{
var min: SCNVector3 = SCNVector3()
var max: SCNVector3 = SCNVector3()
let geom1 = SCNBox(width: boxW, height: boxH, length: boxL, chamferRadius: boxR)
geom1.firstMaterial?.reflective.contents = UIImage(data: BoxData)
geom1.firstMaterial?.reflective.intensity = 1.2
geom1.firstMaterial?.fresnelExponent = 0.25
geom1.firstMaterial?.locksAmbientWithDiffuse = true
geom1.firstMaterial?.diffuse.wrapS = SCNWrapMode.Repeat
let geom2 = SCNSphere(radius: 0.5 * boxH)
geom2.firstMaterial?.reflective.contents = UIImage(data: BalData)
geom2.firstMaterial?.reflective.intensity = 1.2
geom2.firstMaterial?.fresnelExponent = 0.25
geom2.firstMaterial?.locksAmbientWithDiffuse = true
geom2.firstMaterial?.diffuse.wrapS = SCNWrapMode.Repeat
let geom3 = SCNCapsule(capRadius: stickR, height: stickH)
geom3.firstMaterial?.reflective.contents = UIImage(data: StickData)
geom3.firstMaterial?.reflective.intensity = 1.2
geom3.firstMaterial?.fresnelExponent = 0.25
geom3.firstMaterial?.locksAmbientWithDiffuse = true
geom3.firstMaterial?.diffuse.wrapS = SCNWrapMode.Repeat
let box = SCNNode()
box.castsShadow = false
box.position = SCNVector3Zero
box.geometry = geom1
Material.setFirstMaterial(box, materialName: Materials[boxMatId])
let bal = SCNNode()
bal.castsShadow = false
bal.position = SCNVector3(0, 0.15 * boxH, 0)
bal.geometry = geom2
Material.setFirstMaterial(bal, materialName: Materials[balMatId])
let stick = SCNNode()
stick.castsShadow = false
stick.position = SCNVector3Zero
stick.geometry = geom3
stick.getBoundingBoxMin(&min, max: &max)
stick.pivot = SCNMatrix4MakeTranslation(0, min.y, 0)
Material.setFirstMaterial(stick, materialName: Materials[stickMatId])
box.addChildNode(bal)
box.addChildNode(stick)
boxmain = box.flattenedClone()
boxmain.name = "box"
}
Add nodes to the scene:
func Boxesset()
{
let Boxes = SCNNode()
Boxes.name = "Boxes"
var z: Float = -4.5 * radius
for _ in 0..<4
{
var x: Float = -4.5 * radius
for _ in 0..<4
{
let B: SCNNode = boxmain.clone()
B.position = SCNVector3(x: x, y: radius, z: z)
Boxes.addChildNode(B)
x += 3 * Float(radius)
}
z += 3 * Float(radius)
}
self.rootNode.addChildNode(Boxes)
}
This is tested and works great on the simulator - all devices,
on the physical devices - iPad Retina and iPhone 5.
Glitch is observed only at ultra modern iPhone 6s Plus (128 Gb).
The problem is clearly visible on the video ->
The problem with graphics can be solved by changing the Default rendering API to OpenGL ES...
...but you may have unexpected problems in pure computing modules that are not associated with graphics on iPhone 6S Plus. (the iPhone 6 has no such problems).
What's wrong?
TL;DR
Add scnView.prepareObject(boxmain, shouldAbortBlock: nil) to the end of your initBox.
I had a quick look at your code running on my 6s Plus and saw similar results. One of the corner nodes was missing, and was consistently missing each run. But we're not running the same code, mine's missing the materials data...
SceneKit is lazy, often things are not done until an object is added to a scene. I first came across this extracting geometry from a SceneKit primitive (SCNSphere etc), you're finding it when you clone a clone of something via the following lines.
let B: SCNNode = boxmain.clone()
...
boxmain = box.flattenedClone()
I'd say SceneKit is simply not completing the clone before the second clone occurs consistently. I have no way of knowing this for sure.
Removing the first clone fixes this issue for me. For example replace boxmain = box.flattenedClone() with boxmain = box. But I'd say what you've done is best practice, flattening these nodes will reduce the number of draw calls and improve performance (probably not an issue on the 6s).
SceneKit also provides a method - prepareObject:shouldAbortBlock: that will perform the operations required before an object is added to a scene (in this case the .flattenedClone()).
Adding the following line to the end of your initBox function also fixes the problem and is a better solution.
scnView.prepareObject(boxmain, shouldAbortBlock: nil)
Just say, I don't know the right answer to my question, but I found an acceptable solution for myself.
It turned out, it's all in the "diffuse" property of the SCNMaterial.
For whatever reason, Metal does not very like when diffuse = UIColor(...)
But if at least one element in a compound SCNNode (as in my case) is diffuse.contents = UIImage(...), then everything begins to work perfectly.
it works
diffuse=<SCNMaterialProperty: 0x7a6d50a0 | contents=<UIImage: 0x7a6d5b40> size {128, 128} orientation 0 scale 1.000000>
it doesn't work
diffuse=<SCNMaterialProperty: 0x7e611a50 | contents=UIDeviceRGBColorSpace 0.25 0.25 0.25 0.99>
I have found the solution of the problem is simply:
I just added one small, inconspicuous element with diffuse.contents = UIImage(...) to the existing 3 elements with diffuse.contents = UIColor(...) and it worked great.
So, my recommendations:
be careful when working with Metal. (I have a problems on the 5S devices and above)
thoroughly test the SceneKit applications on real devices, don't trust only the simulator
I hope, it's temporary bugs and it will be fix in future releases of Xcode.
Have a nice apps!
P.S. By the way, the finished app is completely free in the AppStore now
Qubic: tic-tac-toe 4x4x4
I'm developing a game on Iphone and Ipad like a space invaders.
Balloons to destroy are falling from the top of the screen in a straight line.
Here my codes to add them :
func addBalloonv(){
var balloonv:SKSpriteNode = SKSpriteNode (imageNamed: "ballonvert.png")
balloonv.physicsBody = SKPhysicsBody (circleOfRadius: balloonv.size.width/2)
balloonv.physicsBody.dynamic = true
balloonv.physicsBody.categoryBitMask = balloonCategory | greenCategory
balloonv.physicsBody.contactTestBitMask = flechetteCategory
balloonv.physicsBody.collisionBitMask = balloonCategory
balloonv.physicsBody.mass = 1
balloonv.physicsBody.restitution = 1
balloonv.physicsBody.allowsRotation = true
let minX = balloonv.size.width/2
let maxX = self.frame.size.width - balloonv.size.width/2
let rangeX = maxX - minX
let position:CGFloat = CGFloat(arc4random()) % CGFloat(rangeX) + CGFloat(minX)
balloonv.position = CGPointMake(position, self.frame.size.height+balloonv.size.height)
self.addChild(balloonv)
I have one func by balloon color.
So for the moment they move in straight line and I'm looking for random movements (with turbulences like balloon in air) from the top and both sides.
How can I do that?
Thank you very much !!
This is exactly what the new Physics Fields feature in SpriteKit (as of iOS 8 / OS X Yosemite) is for. These let you apply different kinds of forces to all physics bodies in region, like gravity, drag, and turbulence. See the SKFieldNode class docs for details.
Fields are a kind of node, so to get what you're after, you'd add one noise (or turbulence) field to your scene, covering the area that the balloons fall through, and it'll perturb the path of each balloon that passes. The simplest way to do it goes something like this:
let field = SKFieldNode.noiseFieldWithSmoothness(0.5, animationSpeed: 0.1)
scene.addChild(field)
You'll want to tweak the smoothness, animation speed, and field.strength till you get just the level of noise you want. You might also look into whether you want just a noise field, which applies random forces in random directions, or a turbulence field, which does the same thing, but with forces that get stronger when bodies are moving faster.
The above code gets you a field whose region of effect is infinite. You might want to limit it to a specific area (for example, so it doesn't keep knocking your balloons around after they land). I did this to make a field that covers only the top 3/4 of a 300x200 scene:
field.region = SKRegion(size: CGSize(width: 300, height: 100))
field.position = CGPoint(x: 150, y: 150)