Code:
func jumpAction(_ JumpPos: CGPoint, _ clickPos: CGPoint) {
if jumpCount < 2 {
var disty = (clickPos.y - JumpPos.y)
var distx = clickPos.x
self.physicsBody?.velocity = CGVector(dx: 0, dy: 0)
self.physicsBody?.applyImpulse(CGVector(dx: distx, dy: disty))
if onGround == false {
jumpCount += 1
}
}
}//
func didBegin(_ other: SKSpriteNode, _ contact: SKPhysicsContact) {
if contact.contactPoint.y < self.frame.minY + 10 {
jumpCount = 1
onGround = true
}
if other.physicsBody?.categoryBitMask == Mask.SpinPlat {
jumpCount = 0
}
}
func didEnd(_ contact: SKPhysicsContact) {
onGround = false
}
I have 3 functions above. The JumpAction is called when I press on the Jump Button on the screen. The didBegin and didEnd functions are called when contact with the top of a platform occurs with the player.
My issue:
So if player is on platform and I jump, the jump action is called before the didEnd function. This is why I have the jumpCount set to 1 when the player contacts the platform. This works fine...
The real issue is when my player lands on the platform, and he bounces slightly off (due to restitution) and then the jump button is pressed.
When this occurs, the onGround flag is flipped to false before the jump action is called and my player can only single jump.
I'm trying to find a simple way to get around this issue without having to implement a bunch of code, haven't found a way yet.
So this is why I am here. I want to be able to double jump even with that slight little bounce I explained earlier.
Thank you in advance!!!
Additional Info:
I use the onGround flag so that if the player is on the ground, he can slide along the ground if they press the jump button in the right location...
Have you tried simply delaying setting the "on ground" flag by a fraction of a second?
let waitAction = SKAction.wait(forDuration: 0.5)
scene.runAction(waitAction, completion: {
self.onGround = false
})
Obviously you could experiment with the exact duration to make sure it gives the "bounce" just enough time to end.
Related
Here is what I'm trying to do: In games, when approaching an NPC, players will be given an indicator to interact with the NPC. The indicator shows up when the player is within a certain distance of the npc. It also goes away when the player moves away from the NPC.
Here is what I tried: I had thought that it would be as easy as using the physics world methods of didBegin/didEnd contact and a transparent cylinder around the NPC as a contact trigger. This unfortunately didn't work because didBegin/didEnd methods are called every frame and not when contact is made (this is how I thought it worked).
I also tried to use PHYKit from GitHub but It didn't seem compatible to what I was trying to do.
I've thought about giving the NPC a Magnetic field and checking if player is within the scope of that field but it doesn't look like there is way to check for that (maybe I missed something).
I thought I could also use hitTestWithSegment but didn't understand how I can apply it to what I'm trying to do.
There also doesn't seem to be anything online to help with this (I've checked for the last three days so if there is anything I'm willing to see what it's about).
The Question: How can I check if a node is within a certain distance of another node and when it left that area?
I still think your physics answer works. Yeah it worked differently than I thought it did too, but you have to play around with it a bit and check it both ways:
func physicsWorld(_ world: SCNPhysicsWorld, didBegin contact: SCNPhysicsContact)
{
if(data.gameState == .run)
{
guard let nodeNameA = contact.nodeA.name else { return }
guard let nodeNameB = contact.nodeB.name else { return }
if(nodeNameA.prefix(5) == "Explo" && nodeNameB.prefix(5) == "Missi")
{
gameControl.enemyMissileHit(vIndex: Int(nodeNameB.suffix(4))!)
}
if(nodeNameA.prefix(5) == "Missi" && nodeNameB.prefix(5) == "Explo")
{
gameControl.enemyMissileHit(vIndex: Int(nodeNameA.suffix(4))!)
}
if(nodeNameA.prefix(5) == "Explo" && nodeNameB.prefix(5) == "Hive ")
{
gameControl.enemyHiveHit(vIndex: Int(nodeNameB.suffix(4))!)
}
if(nodeNameA.prefix(5) == "Hive " && nodeNameB.prefix(5) == "Explo")
{
gameControl.enemyHiveHit(vIndex: Int(nodeNameA.suffix(4))!)
}
}
}
Or - on a timer, check the node distance periodically:
func distance3D(vector1: SCNVector3, vector2: SCNVector3) -> Float
{
let x: Float = (vector1.x - vector2.x) * (vector1.x - vector2.x)
let y: Float = (vector1.y - vector2.y) * (vector1.y - vector2.y)
let z: Float = (vector1.z - vector2.z) * (vector1.z - vector2.z)
let temp = x + y + z
return Float(sqrtf(Float(temp)))
}
Updated Answer:
Here is a better answer and overall more effective than my old answer. It takes advantage of SCNActions with physicsWorld methods and when they are called.
When the first contact between nodes happens, the physicsWorld methods are called in this order:
beginsContact
updateContact
endContact
And as the node proceeds to pass through the other node it goes in this order every other moment:
beginsContact
endContact
updateContact
Once the node is fully inside the other node and moves about inside the node, only this method is called.
updateContact
Note: In my example below, when referring to nodes, I'm talking about the player node and the invisible chatRadius as the other node for an NPC.
Since the beginsContact method is only called when both nodes have their edges touching, I have it set a boolean value equal true.
Note: The bool value is what I use to show interaction indicator for the player and is interchangeable for whatever you what to use.
var interaction: Bool = false
func physicsWorld(_ world: SCNPhysicsWorld, didBegin contact: SCNPhysicsContact) {
let node = (contact.nodeA.name == "player") ? contact.nodeB : contact.nodeA
if node.physicsBody!.categoryBitMask == control.CategoryInteraction && interaction {
interaction = true
}
}
The endContact method is almost always called after the didBegin contact method, so I have it wait for a while before setting the boolean value back to false.
Note: I make the action wait for the updateContact method to be called.
func physicsWorld(_ world: SCNPhysicsWorld, didEnd contact: SCNPhysicsContact) {
let node = (contact.nodeA.name == "player") ? contact.nodeB : contact.nodeA
if node.physicsBody!.categoryBitMask == control.CategoryInteraction && ViewManager.shared.interaction {
let wait = SCNAction.wait(duration: 0.1)
let leave = SCNAction.run { _ in
self.interaction = false
}
let sequence = SCNAction.sequence([wait, leave])
player.runAction(sequence, forKey: "endInteraction")
}
}
The update method is always called when the node moves around the edges or inside the other node. So I have it counter the endContact method by removing the action that would have set the bool value to false.
func physicsWorld(_ world: SCNPhysicsWorld, didUpdate contact: SCNPhysicsContact) {
if player.action(forKey: "endInteraction") != nil {
player.removeAction(forKey: "endInteraction")
}
}
The endContact method is also called when the two nodes stop touching (who would have guessed) and, in my testing, is always the last method to be called.
Old Answer
It's not at all a perfect answer and it still has room for improvement, but for now, this is how I did it.
For the first code section, I am checking to see if the player has collided with the chat radius (or is within a certain distance of the NPC). If the player is inside the radius, then show the indicator to interact with the NPC and add 1 to the count.
var count = 0
var previousCount = 0
func physicsWorld(_ world: SCNPhysicsWorld, didBegin contact: SCNPhysicsContact) {
let node = (contact.nodeA.name == "Player") ? contact.nodeB : contact.nodeA
if node.physicsBody!.categoryBitMask == CategoryInteraction {
// Show chat indicator here.
count += 1
if count > 100 {
count = 0
}
}
}
For the second code section, I'm checking to see if the player has left the chat radius by making the previousCount equal to count. If the count is equal to previousCount, then the player has left the chat radius so hide the interaction indicator.
func physicsWorld(_ world: SCNPhysicsWorld, didEnd contact: SCNPhysicsContact) {
if contact.nodeA.name != "chatRadius" && contact.nodeB.name != "chatRadius" { return }
if previousCount != count {
previousCount = count
} else {
// Hide chat indicator here.
count = 0
previousCount = 0
}
}
I am currently using the WizardCharacter.physicsbody.velocity.dy, and checking if it is equal to 0. I do not want the character to be able to jump in air. The issue I am facing is, my character is resting and he is not moving and the velocity of y is going from 0 to 1 while not doing any actions to the character. I am not sure why this is happening, I am using SpriteKit and SceneKit. I have provided my code, as well a picture for what the console is printing out.
override func update(_ currentTime: TimeInterval) {
print("\(String(describing: wizardCharacter.physicsBody?.velocity.dy))")
cameraNode.position.x = wizardCharacter.position.x
if wizardCharacter.action(forKey: "wizardRun") == nil {
wizardCharacter.texture = SKTexture(imageNamed: "wizard_1_attack-b_001")
}
if upArrow.contains(pointTouched)
{
if wizardCharacter.physicsBody?.velocity.dy == 0 && isJumping == true {
upArrow.alpha = 0.5
jumpWizard(forTheKey: "jumped")
jumpWizardAnimation(fortheKey: "jumpedAnimation")
}
}
It's the third time I'm looking for help in this question.
I have a class name BallNode of kind SKShapeNode. Inside my code I also have a function the spawn ball every 3 second from the top side of the screen. Now, I want to set a function that locate the ball position every 1 second, and so, if the ball.position.y > 200 to print a message to the console.
The purpose of this is that if any ball will be at this position (not while it's falling down) the I will call another function. I tried to do it via SKAction, update(_ currentTime: CFTimeInterval), Timer but I didn't succeed and I really have no idea what to do...
update - my current code:
var timeType1: CFTimeInterval = 0.0
var timeType2: CFTimeInterval = 2.0
override func update(_ currentTime: CFTimeInterval) {
if (currentTime - timeType1 > timeType2){
print("time")
self.checkBallsPosition()
self.timeType1 = currentTime
}
self.enumerateChildNodes(withName: "color.BallNode") { node, _ in
self.checkBallsPosition()
}
}
func checkBallsPosition() {
self.enumerateChildNodes(withName: "BALL") { (node: SKNode, nil) in
let x = self.createTopBorder()
x.isHidden = true
let wait2 = SKAction.wait(forDuration: 1)
let action2 = SKAction.run {
let position = Double(node.position.y)
if position < 200 {
}
else if position > 200 {
print("bolbo")
node.removeFromParent()
}
}
self.run(SKAction.sequence([wait2,action2]))
}
}
thats what I try do to so far, as I said the problem is that I want to get the ball last position. because the ball fall down the screen the last position should be when it touch the bottom border of the screen or when it touches another ball. if I set it at update I get the ball position every frame or (as I did) every second - but not the last. another problem is that the ball position can always change depends on another balls (when collision occurs).
update #2 - another functions:
func spawnBalls() {
let wait = SKAction.wait(forDuration: 3)
let action = SKAction.run {
self.createBall()
}
run(SKAction.repeatForever((SKAction.sequence([wait, action]))))
}
func createBall(){
let ball = BallNode(radius: 65)
print(ball.Name)
print(ball._subName!)
ball.position.y = ((frame.size.height) - 200)
let ballXPosition = arc4random_uniform(UInt32(frame.size.width))
ball.position.x = CGFloat(ballXPosition)
ball.physicsBody?.categoryBitMask = PhysicsCategory.ball
ball.physicsBody?.collisionBitMask = PhysicsCategory.ball
ball.physicsBody?.contactTestBitMask = PhysicsCategory.topBorder
ball.delegate = self
addChild(ball)
}
You did not post the entire code you are using. Not knowing how you are spawning your balls, how is the hierarchy and how you are moving them, I can't reproduce it here.
I am not sure if I understand it right, but I believe it might be simpler than what you are doing. See if the code below helps you, I am making the balls fall with SKAction (you can do it with physics also), and checking when they go below zero, when I remove them.
private let ballSpeed : CGFloat = 400
private let ballRadius : CGFloat = 10
private func spawnBall(atPoint pos : CGPoint){
let b = SKShapeNode(circleOfRadius: ballRadius)
b.name = "ball"
b.position = pos
addChild(b)
b.run(SKAction.moveTo(y: -size.height, duration: TimeInterval((pos.y+size.height)/400)))
}
override func update(_ currentTime: TimeInterval) {
super.update(currentTime)
enumerateChildNodes(withName: "ball") { (node, _) in
if node.position.y < 0 {
node.removeFromParent()
}
}
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
for touch in touches{
let pos = touch.location(in: self)
spawnBall(atPoint: pos)
}
}
I'm having an issue with contact detection in Swift 3 using SpriteKit. The contact detection is working...sometimes. It seems purely random as to when it fires and when it doesn't.
I have a yellow "bullet" that moves up on the screen to hit a red sprite named targetSprite. The desired behavior is to have the bullet removed when it hits the target, but sometimes it just passes through underneath.
I've found many questions about contact detection not working at all, but I haven't found any dealing with inconsistent detection.
What can I do to fix this?
Here's the code:
import SpriteKit
import GameplayKit
enum PhysicsCategory:UInt32 {
case bullet = 1
case sprite1 = 2
case targetSprite = 4
// each new value should double the previous
}
class GameScene: SKScene, SKPhysicsContactDelegate {
// Create sprites
let sprite1 = SKSpriteNode(color: SKColor.blue, size: CGSize(width:100,height:100))
let targetSprite = SKSpriteNode(color: SKColor.red, size: CGSize(width:100,height:100))
let bullet = SKSpriteNode(color: SKColor.yellow, size: CGSize(width: 20, height: 20))
// show the bullet?
var isShowingBullet = true
// Timers
//var timer:Timer? = nil
var fireBulletTimer:Timer? = nil
// set up bullet removal:
var bulletShouldBeRemoved = false
let bulletMask = PhysicsCategory.bullet.rawValue
override func didMove(to view: SKView) {
// Physics
targetSprite.physicsBody = SKPhysicsBody(rectangleOf: targetSprite.centerRect.size)
targetSprite.physicsBody?.affectedByGravity = false
bullet.physicsBody = SKPhysicsBody(rectangleOf: bullet.centerRect.size)
bullet.physicsBody?.affectedByGravity = false
// Contact Detection:
targetSprite.physicsBody?.categoryBitMask = PhysicsCategory.targetSprite.rawValue
targetSprite.physicsBody?.contactTestBitMask =
//PhysicsCategory.sprite1.rawValue |
PhysicsCategory.bullet.rawValue
targetSprite.physicsBody?.collisionBitMask = 0 // no collision detection
// bullet physics
bullet.physicsBody?.categoryBitMask = PhysicsCategory.bullet.rawValue
bullet.physicsBody?.contactTestBitMask =
PhysicsCategory.targetSprite.rawValue
bullet.physicsBody?.collisionBitMask = 0 // no collision detection
// execute once:
fireBulletTimer = Timer.scheduledTimer(timeInterval: 1,
target: self,
selector: #selector(self.fireBullet),
userInfo: nil,
repeats: false)
// Add sprites to the scene:
self.addChild(sprite1)
self.addChild(bullet)
self.addChild(targetSprite)
// Positioning
targetSprite.position = CGPoint(x:0, y:300)
// Note: bullet and sprite1 are at 0,0 by default
// Delegate
self.physicsWorld.contactDelegate = self
}
func didBegin(_ contact: SKPhysicsContact) {
print("didBegin(contact:))")
//let firstBody:SKPhysicsBody
// let otherBody:SKPhysicsBody
// Use 'bitwise and' to see if both bits are 1:
if contact.bodyA.categoryBitMask & bulletMask > 0 {
//firstBody = contact.bodyA
//otherBody = contact.bodyB
print("if contact.bodyA....")
bulletShouldBeRemoved = true
}
else {
//firstBody = contact.bodyB
//otherBody = contact.bodyA
print("else - if not contacted?")
}
/*
// Find the type of contact:
switch otherBody.categoryBitMask {
case PhysicsCategory.targetSprite.rawValue: print(" targetSprite hit")
case PhysicsCategory.sprite1.rawValue: print(" sprite1 hit")
case PhysicsCategory.bullet.rawValue: print(" bullet hit")
default: print(" Contact with no game logic")
}
*/
} // end didBegin()
func didEnd(_ contact: SKPhysicsContact) {
print("didEnd()")
}
func fireBullet() {
let fireBulletAction = SKAction.move(to: CGPoint(x:0,y:500), duration: 1)
bullet.run(fireBulletAction)
}
func showBullet() {
// Toggle to display or not, every 1 second:
if isShowingBullet == true {
// remove (hide) it:
bullet.removeFromParent()
// set up the toggle for the next call:
isShowingBullet = false
// debug:
print("if")
}
else {
// show it again:
self.addChild(bullet)
// set up the toggle for the next call:
isShowingBullet = true
// debug:
print("else")
}
}
override func update(_ currentTime: TimeInterval) {
// Called before each frame is rendered
if bulletShouldBeRemoved {
bullet.removeFromParent()
}
}
}
Sorry for the inconsistent indentation, I can't seem to find an easy way to do this...
EDIT:
I have found that using 'frame' instead of 'centerRect' makes the collision area the size of the sprite. For example:
targetSprite.physicsBody = SKPhysicsBody(rectangleOf: targetSprite.centerRect.size)
should be:
targetSprite.physicsBody = SKPhysicsBody(rectangleOf: targetSprite.frame.size)
First advice - Do not use NSTimer (aka Timer) in SpriteKit. It is not paired with a game loop and can cause different issues in a different situations. Read more here ( answer posted by LearnCocos2D)
So, do this:
let wait = SKAction.wait(forDuration: 1)
run(wait, completion: {
[unowned self] in
self.fireBullet()
})
What I have noticed is that if I run your code in Simulator, I get the behaviour you have described. didBegin(contact:) is being fired randomly. Still, this is not happening on a device for me, and device testing is what matters.
Now, when I have removed Timer and did the same thing with SKAction(s) everything worked, means contact were detected every time.
Have you tried adding
.physicsBody?.isDynamic = true
.physicsBody?.usesPreciseCollisionDetrction =true
SpriteKit physics engine will calculate collision correctly if you do following:
1) set "usesPreciseCollisionDetection" property to true for bullet's physics body. This will change collision detection algorithm for this body. You can found more information about this property here, chapter "Working with Collisions and Contacts".
2) move your bullet using applyImpulse or applyForce methods. Collision detection will not woking correctly if you move body by changing it's position manually. You can find more information here, chapter "Making Physics Bodies Move".
Hey so I am making this project in which the player has to jump platforms all the way to the top. Some monsters spawn randomly throughout the game. So the idea is to lose the game when you hit them from below, but can go on if you jump on them. I already did the part in which the player jumps on it and you destroy the monster but I am still stuck on that part to lose the game when you hit it from below. Any ideas on how I can manage to do this? For this project I followed Ray Wenderlich's tutorial on How To Make a Game Like Mega Jump.
So on my GameScene, I have the didBeginContact method:
func didBeginContact(contact: SKPhysicsContact) {
var updateHUD = false
let whichNode = (contact.bodyA.node != player) ? contact.bodyA.node : contact.bodyB.node
let other = whichNode as GameObjectNode
updateHUD = other.collisionWithPlayer(player)
if updateHUD {
lblStars.text = String(format: "X %d", GameState.sharedInstance.stars)
lblScore.text = String(format: "%d", GameState.sharedInstance.score)
}
}
Which then calls the method from the GameObjectNode Scene.
class MonsterNode: GameObjectNode {
var monsterType: MonsterType!
override func collisionWithPlayer(player: SKNode) -> Bool {
if player.physicsBody?.velocity.dy < 0 {
player.physicsBody?.velocity = CGVector(dx: player.physicsBody!.velocity.dx, dy: 450.0)
if monsterType == .Normal {
self.removeFromParent()
}
}
When the player jumps on top of the monster, the monster is removed from the parent. I was trying to set that if the player's velocity is greater than 0 when colliding with the monster, then the player is removed from parent. Then when I go back to my GameScene, I could declare something in my update method so that when the player is removed from the parent call the endGame() method.
override func update(currentTime: NSTimeInterval) {
if gameOver {
return
}
if Int(player.position.y) > endLevelY {
endGame()
}
if Int(player.position.y) < maxPlayerY - 500 {
endGame()
}
}
Of course I wasn't able to make that work, and I still can't. So if anyone could help me out on how I can manage to do this, or probably some tutorial which could guide me into doing this I would really appreciate it! Thank you in advance.
First you use the didBeginContact method to establish if a contact between player and monster has been made. Next you compare the y positions of the player and monster. If the monster's y position is greater than than the player's... BANG, player dies.
The code sample assumes you have multiple monsters, each with a unique name, and have them all stored in an array.
- (void)didBeginContact:(SKPhysicsContact *)contact {
uint32_t collision = (contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask);
if (collision == (CategoryMonster | CategoryPlayer)) {
for(SKSpriteNode *object in monsterArray) {
if(([object.name isEqualToString:contact.bodyB.node.name]) || ([object.name isEqualToString:contact.bodyA.node.name])) {
if(object.position.y > player.position.y) {
// moster is above player
}
}
}
}
Couple of notes... If you have more than one monster active at any one time, you will need to have a unique name for each one. Reason being that you will need to know which monster contacted the player and that can only happen if you can differentiate between monsters. Hence the unique name for each one.
The if check for the y position is a simple one and only needs +1 y to be fulfilled. If it is possible for your player to make side contact with a monster and not die, you can change the if condition to be something like if(object.position.y > player.position.y+50) to make sure that the contact was actually from the bottom.
(I am not all too proficient in Swift yet so code sample is in Obj-C.)