I'm trying to create a snake with multiple body parts that moves left and right. Im using a pin, but upon the snake stopping, the body keeps moving and doesn't stop. I've messed around with the max and min angles, and the torque, but nothing seems to work. Should I use a different type of joint?
Sorry i cant log into my other account, but heres the code. Basically the second part just wobbles a lot. I wish to add 7-8 parts, but they just keep on wobbling, especially after moving "head". i would like a fluid "swoop" motion when i move the snake.
self.physicsWorld.gravity = CGVectorMake(0, -100)
self.physicsWorld.contactDelegate = self
head.size = CGSize(width: 25,height: 25)
head.physicsBody = SKPhysicsBody(texture: head.texture, size: head.size)
head.position = CGPointMake(100,400)
head.anchorPoint = CGPoint(x: 0.5, y: 1)
head.physicsBody!.dynamic = false
head.zPosition = 3
self.addChild(head)
var p1 = SKSpriteNode(imageNamed: "snakeBodyPart.png")
p1.size = CGSize(width: 25,height: 25)
p1.physicsBody = SKPhysicsBody(texture: p1.texture, size: p1.size)
p1.position = CGPointMake(100,380)
p1.anchorPoint = CGPoint(x: 0.5, y: 1)
p1.physicsBody!.dynamic = true
addChild(p1)
var joint = SKPhysicsJointPin.jointWithBodyA(head.physicsBody, bodyB: p1.physicsBody, anchor: CGPoint(x: CGRectGetMidX(head.frame), y: CGRectGetMinY(head.frame) + 10))
joint.upperAngleLimit = 0.1
joint.rotationSpeed = 0.1
self.physicsWorld.addJoint(joint)
Related
I'm working on an Xcode Playground and I'm having some problems with SpriteKit collisions.
The first box has a mass of 1 and the second box has a mass of 100000 (when the latter is 100, for example, everything works fine). The collisions are elastic (restitution was set to 1) and there is no friction or damping at all.
Here is the code for my scene (ColliderType is just an enum for the categories):
class GameScene: SKScene {
private var wall: SKSpriteNode!
private var floor: SKSpriteNode!
private var box1: SKSpriteNode!
private var box2: SKSpriteNode!
override func didMove(to view: SKView) {
self.backgroundColor = .white
wall = SKSpriteNode(color: SKColor.black, size: CGSize(width: 10, height: self.frame.height))
wall.position = CGPoint(x: 100, y: self.frame.height/2)
wall.physicsBody = SKPhysicsBody(rectangleOf: wall.frame.size)
wall.physicsBody?.isDynamic = false
floor = SKSpriteNode(color: SKColor.black, size: CGSize(width: self.frame.width, height: 10))
floor.position = CGPoint(x: self.frame.width/2, y: 100)
floor.physicsBody = SKPhysicsBody(rectangleOf: floor.frame.size)
floor.physicsBody?.isDynamic = false
box1 = SKSpriteNode(color: SKColor.black, size: CGSize(width: 100, height: 100))
box1.position = CGPoint(x: 300, y: floor.position.y+box1.size.height/2)
box1.physicsBody = SKPhysicsBody(circleOfRadius: box1.frame.size.width/2)
box2 = SKSpriteNode(color: SKColor.black, size: CGSize(width: 100, height: 100))
box2.position = CGPoint(x: 750, y: floor.position.y+box2.size.height/2)
box2.physicsBody = SKPhysicsBody(circleOfRadius: box2.frame.size.width/2)
self.addChild(wall)
self.addChild(floor)
self.addChild(box1)
self.addChild(box2)
box1.physicsBody?.allowsRotation = false
box2.physicsBody?.allowsRotation = false
box1.physicsBody?.restitution = 1
box2.physicsBody?.restitution = 1
box1.physicsBody?.mass = 1
box2.physicsBody?.mass = 100000
box1.physicsBody?.friction = 0
box2.physicsBody?.friction = 0
box1.physicsBody?.linearDamping = 0
box2.physicsBody?.linearDamping = 0
wall.physicsBody?.categoryBitMask = ColliderType.Wall.rawValue
box1.physicsBody?.categoryBitMask = ColliderType.Box1.rawValue
box2.physicsBody?.categoryBitMask = ColliderType.Box2.rawValue
box1.physicsBody?.collisionBitMask = ColliderType.Wall.rawValue | ColliderType.Floor.rawValue | ColliderType.Box2.rawValue
box2.physicsBody?.collisionBitMask = ColliderType.Floor.rawValue | ColliderType.Box1.rawValue
box1.physicsBody?.contactTestBitMask = ColliderType.Box2.rawValue | ColliderType.Wall.rawValue
box1.physicsBody?.velocity = CGVector(dx: 0, dy: 0)
box2.physicsBody?.velocity = CGVector(dx: -50, dy: 0)
}
}
Things I've tried:
Set usesPreciseCollisionDetection = true on the first box
Update the positions and check for collisions by myself by overriding the update method (it wasn't as optimised as SpriteKit's engine so it was very slow)
Make the second box slower and set physicsWorld.speed to a number higher than 1
I think in general you're probably expecting too much. SpriteKit is a game engine, designed to give qualitatively reasonable behavior for scenarios involving normal-ish sorts of physics. It's not a high-precision physics simulation, and when you push it into a region where it's got to do something extreme, it's probably going to fail.
In this case, you're expecting it to simulate a huge number of perfectly elastic collisions within a small amount of time and distance (many collisions per animation frame of the simulation as the heavy block mashes the light one into a tiny gap). It's going to find the first collision in the frame, figure the impulses to apply to the blocks, and then advance to the next frame, with the effect that the big block happily mashes into the space where the small one resides. All the subsequent collisions that would prevent that are being missed in search of 60 fps.
I want to create a game with rectangles which move by x and by y.
My question is: Have I move the view (viewer of the player) or have I move the rectangles by x and by y at the same time?
I tried to move rectangles by x and by y at the same time, with the following code, but the rectangles move only by y.
#objc func addRects() {
rects = GKRandomSource.sharedRandom().arrayByShufflingObjects(in: rects) as! [String]
rect = SKSpriteNode(imageNamed: rects[0])
rect.position = CGPoint(x: self.frame.width / 256 + 320, y: self.frame.height / 256)
rect.size = CGSize(width: 180, height: 120)
rect.zPosition = 1
self.addChild(rect)
moveByX = SKAction.moveTo(x: -500, duration: 2.0)
moveByY = SKAction.moveTo(y: -800, duration: 2.0)
removeRects = SKAction.removeFromParent()
wait = SKAction.wait(forDuration: 2.0)
rect.run(SKAction.sequence([moveByY,moveByY]))
rect.run(SKAction.sequence([wait,removeRects]))
}
How can I resolve this problem ?
Thank you
Don't use a sequence:
rect.run(moveByY)
rect.run(moveByX)
then it should move at the same time "moveByY" and "moveByX"
The other problem is, that you used:
rect.run(SKAction.sequence([moveByY,moveByY]))
I Hope my answer helps!
so I know this is a dumb question, but maybe it'll help other people like me out too. Basically, I'm making a sprite appear at the top of the screen and then move to the bottom but in a random x position. There's nothing wrong with moving to the random x position, the problem is that it doesn't start out at the top of the screen. Here is my code:
let sprite = SKSpriteNode(imageNamed: "comet")
sprite.size = CGSize(width: 150, height: 100)
sprite.position = CGPoint(x: self.frame.size.width/2, y: 0)
sprite.zPosition = 100
self.addChild(sprite) `
let randomNum = CGPoint(x:Int (arc4random() % 1000), y: 1)
let actionMove = SKAction.moveTo(randomNum, duration: 1)
let actionComet = SKAction(actionMove)
sprite.runAction(actionComet)
Any help is appreciated.
You are placing your sprite at location (0,0) which is left bottom of the screen. If you want to place the sprite at the top use:
sprite.position = CGPoint(x: self.frame.size.width/2, y: self.frame.size.height + sprite.size.height / 2.0)
please forgive me as I'm a bit of a Swift noob and am creating my first game :D
Ok, so I have two nodes... one is Guava and the other is Pepper. Guava moves from the bottom of the screen to the top. I want the Pepper to move from the top of the screen to the bottom. Here's the code I have, which works fine for the Guava.
// movement of guavas
let guavaToMove = CGFloat(self.frame.size.width + 2.0 * guavaNodeTexture.size().width)
let moveGuava = SKAction.moveByX(-guavaToMove, y: self.frame.size.width, duration: NSTimeInterval(0.01 * guavaToMove))
let removeGuava = SKAction.removeFromParent()
// movement of peppers
let pepperToMove = CGFloat(self.frame.size.width + 2.0 * pepperNodeTexture.size().width)
let movePepper = SKAction.moveByX(-pepperToMove, y: self.frame.size.width, duration: NSTimeInterval(0.01 * pepperToMove))
let removePepper = SKAction.removeFromParent()
GuavaMoveAndRemove = SKAction.sequence([moveGuava,removeGuava])
PepperMoveAndRemove = SKAction.sequence([movePepper,removePepper])
Now I have the Guava Node anchored to the bottom of the screen and it floats up perfectly. I have the Pepper Node anchored to the top of the screen and am trying to get it to float down in a similar fashion.
Here is the code for both functions, spawnGuava and spawnPepper where both nodes/textures are anchored:
func spawnPepper(){
//The way the Guava spawn and move
let pepperNode = SKNode()
let pepper = SKSpriteNode(texture: pepperNodeTexture)
pepper.setScale(0.30)
pepper.position = CGPointMake (self.size.width + 140, self.size.height * 0.75)
pepper.alpha = 0.75
pepper.physicsBody = SKPhysicsBody(rectangleOfSize: pepper.size)
pepper.physicsBody?.affectedByGravity = false
pepper.physicsBody?.dynamic = true
pepper.physicsBody?.categoryBitMask = PhysicsCatagory.Guava
pepper.physicsBody?.collisionBitMask = 1
pepper.physicsBody?.contactTestBitMask = PhysicsCatagory.Boognish
pepper.zPosition = 50
pepperNode.addChild(pepper)
pepper.runAction(PepperMoveAndRemove)
self.addChild(pepperNode)
if scoreIncreased == true {
}
//the way the pepper collide
}
func spawnGuava(){
//The way the Guava spawn and move
let guavaNode = SKNode()
let guava = SKSpriteNode(texture: guavaNodeTexture)
guava.setScale(0.75)
guava.position = CGPointMake (self.size.width - 40, self.size.height * 0.05)
guava.physicsBody = SKPhysicsBody(rectangleOfSize: guava.size)
guava.physicsBody?.affectedByGravity = false
guava.physicsBody?.dynamic = true
guava.alpha = 0.75
guava.physicsBody?.categoryBitMask = PhysicsCatagory.Guava
guava.physicsBody?.collisionBitMask = 1
guava.physicsBody?.contactTestBitMask = PhysicsCatagory.Boognish
guava.zPosition = 0
guavaNode.addChild(guava)
guava.runAction(GuavaMoveAndRemove)
self.addChild(guavaNode)
if scoreIncreased == true {
}
//the way the guava collide
}
Please help me configure this code accordingly so that the peppers fall from the sky :)
THANKS in advance. First post :)
FYI: I have tried modifying the code many times myself to no avail, so I have reverted it to the baseline you see now. IF I anchored the pepper to where the Guava is anchored then both would float up at the same time.
You're trying to move guavas and peppers in the opposite direction, but it seems like you are moving them in the same direction. Try removing or adding negative signs in movePepper:
let movePepper = SKAction.moveByX(-pepperToMove, y: -self.frame.size.width, duration: NSTimeInterval(0.01 * pepperToMove))
// movement of peppers
let pepperToMove = CGFloat(self.frame.size.width + 2.0 * pepperNodeTexture.size().width)
let movePepper = SKAction.moveByX(-pepperToMove, y: self.frame.size.height / -1, duration: NSTimeInterval(0.01 * pepperToMove))
let removePepper = SKAction.removeFromParent()
just has to divide the y value by a negative, derp... :D
I have a problem in my code. When I run the game, I have two obstacles (one on the left and one on the right). I coded a gap between each obstacle and it has been working. I have a problem where the gap sometimes spawns off of the screen where the player cannot get to. How can I fix this?
Here's my code:
let gapWidth = square.size.width * 1.5
var movementAmount = arc4random() % UInt32(self.frame.size.width/2)
var obstacleOffset = CGFloat(movementAmount) - self.frame.size.width / 2
var obstacle1 = SKSpriteNode(imageNamed: "Obstacle")
obstacle1.zPosition = 30
obstacle1.size = CGSize(width: self.frame.size.width, height: 300)
obstacle1.position = CGPoint(x: CGRectGetMidX(self.frame) + obstacle1.size.width / 2 + gapWidth / 2 + obstacleOffset, y: CGRectGetMidY(self.frame))
self.addChild(obstacle1)
var obstacle2 = SKSpriteNode(imageNamed: "Obstacle")
obstacle2.zPosition = 30
obstacle2.size = CGSize(width: self.frame.size.width, height: 300)
obstacle2.position = CGPoint(x: CGRectGetMidX(self.frame) - obstacle2.size.width / 2 - gapWidth / 2 + obstacleOffset, y: CGRectGetMidY(self.frame))
self.addChild(obstacle2)
You need to make sure the values of the random positions will always be on the screen. You can do that by using code similar to this:
var height = UInt32(self.frame.size.height)
var randomYPos = CGFloat(arc4random_uniform(UInt32(height)))
You can do the same for the random x value, just use the screen width. You only need to do this for obstacle 1, then set the position of obstacle 2 relative to obstacle 1.