I have a Player which is a custom SKShapeNode class object.
I added a camera to follow the player, it is working but I want the camera to follow the player more frequently. now it is just checking if the camera still has player inside its view, if it doesn't it moves the camera.
I tried to check the height of the screen and move it when I get close to the top but it didn't work.
This is the code I have now (runs in update() function):
if (!cameraNode.contains(mPlayer)) {
moveCamera()
}
this is moveCamera():
func moveCamera(){
let moveAction = SKAction.moveTo(y: mPlayer.position.y + 600, duration: 0.1)
cameraNode.run(moveAction)
}
It depends how your scene is set up, but this might work:
let idealDistance: CGFloat = 600.0
let allowedDelta: CGFloat = 150.0
let offset = cameraNode.position.y - (mPlayer.position.y + idealDistance)
if abs(offset) > allowedDelta {
moveCamera()
}
You can experiment with the allowedDelta value to see what works nicely.
Related
I put some objects in AR space using ARKit and SceneKit. That works well. Now I'd like to add an additional camera (SCNCamera) that is placed elsewhere in the scene attached and positioned by a common SCNNode. It is oriented to show me the current scene from an other (fixed) perspective.
Now I'd like to show this additional SCNCamera feed on i.Ex. a SCNPlane (as the diffuse first material) - Like a TV screen. Of course I am aware that it will only display the SceneKit content which stays in the camera focus and not rest of the ARKit image (which is only possible by the main camera of course). A simple colored background then would be fine.
I have seen tutorials that describes, how to play a video file on a virtual display in ARSpace, but I need a realtime camera feed from my own current scene.
I defined this objects:
let camera = SCNCamera()
let cameraNode = SCNNode()
Then in viewDidLoad I do this:
camera.usesOrthographicProjection = true
camera.orthographicScale = 9
camera.zNear = 0
camera.zFar = 100
cameraNode.camera = camera
sceneView.scene.rootNode.addChildNode(cameraNode)
Then I call my setup function to place the virtual Display next to all my AR stuff, position the cameraNode as well (pointing in the direction where objects stay in the scene)
cameraNode.position = SCNVector3(initialStartPosition.x, initialStartPosition.y + 0.5, initialStartPosition.z)
let cameraPlane = SCNNode(geometry: SCNPlane(width: 0.5, height: 0.3))
cameraPlane.geometry?.firstMaterial?.diffuse.contents = cameraNode.camera
cameraPlane.position = SCNVector3(initialStartPosition.x - 1.0, initialStartPosition.y + 0.5, initialStartPosition.z)
sceneView.scene.rootNode.addChildNode(cameraPlane)
Everything compiles and loads... The display shows up at the given position, but it stays entirely gray. Nothing is displayed at all from the SCNCamera I put in the scene. Everything else in the AR scene works well, I just don't get any feed from that camera.
Hay anyone an approach to get this scenario working?
To even better visualize, I add some more print screens.
The following shows the Image trough the SCNCamera according to ARGeo's input. But it takes the whole screen, instead of displaying its contents on a SCNPlane, like I need.
The next Print screen actually shows the current ARView result as I got it using my posted code. As you can see, the gray Display-Plane remains gray - it shows nothing.
The last print screen is a photomontage, showing the expected result, as I'd like to get.
How could this be realized? Am I missing something fundamental here?
After some research and sleep, I came to the following, working solution (including some inexplainable obstacles):
Currently, the additional SCNCamera feed is not linked to a SCNMaterial on a SCNPlane, as it was the initial idea, but I will use an additional SCNView (for the moment)
In the definitions I add an other view like so:
let overlayView = SCNView() // (also tested with ARSCNView(), no difference)
let camera = SCNCamera()
let cameraNode = SCNNode()
then, in viewDidLoad, I setup the stuff like so...
camera.automaticallyAdjustsZRange = true
camera.usesOrthographicProjection = false
cameraNode.camera = camera
cameraNode.camera?.focalLength = 50
sceneView.scene.rootNode.addChildNode(cameraNode) // add the node to the default scene
overlayView.scene = scene // the same scene as sceneView
overlayView.allowsCameraControl = false
overlayView.isUserInteractionEnabled = false
overlayView.pointOfView = cameraNode // this links the new SCNView to the created SCNCamera
self.view.addSubview(overlayView) // don't forget to add as subview
// Size and place the view on the bottom
overlayView.frame = CGRect(x: 0, y: 0, width: self.view.bounds.width * 0.8, height: self.view.bounds.height * 0.25)
overlayView.center = CGPoint(x: self.view.bounds.width * 0.5, y: self.view.bounds.height - 175)
then, in some other function, I place the node containing the SCNCamera to my desired position and angle.
// (exemplary)
cameraNode.position = initialStartPosition + SCNVector3(x: -0.5, y: 0.5, z: -(Float(shiftCurrentDistance * 2.0 - 2.0)))
cameraNode.eulerAngles = SCNVector3(-15.0.degreesToRadians, -15.0.degreesToRadians, 0.0)
The result, is a kind of window (the new SCNView) at the bottom of the screen, displaying the same SceneKit content as in the main sceneView, viewed trough the perspective of the SCNCamera plus its node position, and that very nicely.
In a common iOS/Swift/ARKit project, this construct generates some side effects, that one may struggle into.
1) Mainly, the new SCNView shows SceneKit content from the desired perspective, but the background is always the actual physical camera feed. I could not figure out, how to make the background a static color, by still displaying all the SceneKit content. Changing the new scene's background property affects also the whole main scene, what is actually NOT desired.
2) It might sound confusing, but as soon as the following code get's included (which is essential to make it work):
overlayView.scene = scene
the animation speed of the entire scenes (both) DOUBLES! (Why?)
I got this corrected by adding/changing the following property, which restores the animation speed behavour almost like normal (default):
// add or change this in the scene setup
scene.physicsWorld.speed = 0.5
3) If there are actions like SCNAction.playAudio in the project, all the effects will no longer play - as long as I don't do this:
overlayView.scene = nil
Of course, the additional SCNView stops working but everything else gets gets back to its normal.
Use this code (as a starting point) to find out how to setup a virtual camera.
Just create a default ARKit project in Xcode and copy-paste my code:
import UIKit
import SceneKit
import ARKit
class ViewController: UIViewController, ARSCNViewDelegate {
#IBOutlet var sceneView: ARSCNView!
override func viewDidLoad() {
super.viewDidLoad()
sceneView.delegate = self
sceneView.showsStatistics = true
let scene = SCNScene(named: "art.scnassets/ship.scn")!
sceneView.scene = scene
let cameraNode = SCNNode()
cameraNode.camera = SCNCamera()
cameraNode.position = SCNVector3(0, 0, 1)
cameraNode.camera?.focalLength = 70
cameraNode.camera?.categoryBitMask = 1
scene.rootNode.addChildNode(cameraNode)
sceneView.pointOfView = cameraNode
sceneView.allowsCameraControl = true
sceneView.backgroundColor = UIColor.darkGray
let plane = SCNNode(geometry: SCNPlane(width: 0.8, height: 0.45))
plane.position = SCNVector3(0, 0, -1.5)
// ASSIGN A VIDEO STREAM FROM SCENEKIT-RECORDER TO YOUR MATERIAL
plane.geometry?.materials.first?.diffuse.contents = capturedVideoFromSceneKitRecorder
scene.rootNode.addChildNode(plane)
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
let configuration = ARWorldTrackingConfiguration()
sceneView.session.run(configuration)
}
}
UPDATED:
Here's a SceneKit Recorder App that you can tailor to your needs (you don't need to write a video to disk, just use a CVPixelBuffer stream and assign it as a texture for a diffuse material).
Hope this helps.
I'm a little late to the party, but I've had a similar issue recently.
As far as I can tell, you cannot directly connect a camera to a node's material. You can, however, use a scene's layer as a texture for a node.
The code below is not verified, but should be more or less ok:
class MyViewController: UIViewController {
override func loadView() {
let projectedScene = createProjectedScene()
let receivingScene = createReceivingScene()
let projectionPlane = receivingScene.scene?.rootNode.childNode(withName: "ProjectionPlane", recursively: true)!
// Here's the important part:
// You can't directly connect a camera to a material's diffuse texture.
// But you can connect a scene's layer as a texture.
projectionPlane.geometry?.firstMaterial?.diffuse.contents = projectedScene.layer
projectedScene.layer.contentsScale = 1
// Note how we only need to connect the receiving view to the controller.
// The projected view is not directly connected as a subview,
// but updates in projectedScene will still be reflected in receivingScene.
self.view = receivingScene
}
func createProjectedScene() -> SCNView {
let view = SCNView()
// ... set up scene ...
return view
}
func createReceivingScene() -> SCNView {
let view = SCNView()
// ... set up scene ...
let projectionPlane = SCNNode(geometry: SCNPlane(width: 2, height: 2)
projectionPlane.name = "ProjectionPlane"
view.scene.rootNode.addChildNode(projectionPlane)
return view
}
}
I'm creating a simple game with Swift and SpriteKit.
I want to add an endless background (vertically), I only found answers for background with images but I need to do it without image, only background color.
I thought about checking if the player is in the frame.maxY, if so, to move it back to the starting point, but I was wondering if there is a better idea.
//Does not matter which ring we chose as all ring's 'y' position is the same.
func moveBackgroundUp(){
if ((mPlayer.position.y >= self.frame.maxY) || (mRingOne.position.y >= self.frame.maxY)) {
mPlayer.position.y = 150 //mPlayers original starting point.
for ring in mRings {
ring.position.y = 350
}
}
}
Thanks in advance!
Don't just move a background up the screen, that' really isn't the way to go about it. What you should do is detect the position of the camera (assuming it moves with the player), and when it's position is about to occupy space outside of the occupied space of your current background sprite, add a new background sprite to the scene where the last one left off. Here is an example of how to do that with just a red sprite:
First add a property to the scene to track level position:
// To track the y-position of the level
var levelPositionY: CGFloat = 0.0
Now create a method to update your background:
func updateBackground() {
let cameraPos = camera!.position
if cameraPos.y > levelPositionY - (size.height * 0.55) {
createBackground()
}
}
func createBackground() {
// Create a new sprite the size of your scene
let backgroundSprite = SKSpriteNode(color: .red, size: size)
backgroundSprite.anchorPoint = CGPoint(x: 0.5, y: 0)
backgroundSprite.position = CGPoint(x: 0, y: levelPositionY)
// Replace backgroundNode with the name of your backgroundNode to add the sprite to
backgroundNode.addChild(backgroundSprite)
levelPositionY += backgroundSprite.size.height
}
Now you want to call updateBackground inside your overridden update(_:) method:
override func update(_ currentTime: TimeInterval) {
// All your other update code
updateBackground()
}
Also, make sure to create an initial background when you first create the scene:
override func didMove(to view: SKView) {
createBackground()
}
NOTE! - It's important to set the custom anchor point for the background sprite for this code to work properly. An anchor of (0.5, 0) allows the background sprite to be anchored in the middle of the scene on the x-axis, but at the bottom of the scene on the y-axis. This allows you to easily stack one on top of the other.
EDIT - I forgot to mention that it's also a good idea to conserve resources and remove any background nodes that are outside the viewable area and won't be coming back in (i.e. a continuous scrolling game where you can't go backwards). You could do that by updating your updateBackground method above:
func updateBackground() {
let cameraPos = camera!.position
if cameraPos.y > levelPositionY - (size.height * 0.55) {
createBackground()
}
// Make sure to change 'backgroundNode' to whatever the name of your backgroundNode is.
for bgChild in backgroundNode.children {
// This will convert the node's coordinates to scene's coordinates. See below for this function
let nodePos = fgNode.convert(fgChild.position, to: self)
if !isNodeVisible(bgChild, positionY: nodePos.y) {
// Remove from it's parent node
bgChild.removeFromParent()
}
}
}
func isNodeVisible(_ node: SKNode, positionY: CGFloat) -> Bool {
if !camera!.contains(node) {
if positionY < camera!.position.y - size.height * 2.0 {
return false
}
}
return true
}
So above you just loop through all the children inside your background node and detect if they are out of view, and if so remove them from the parent. Make sure to change my generic backgroundNode to whatever the name of your background node is.
I am creating a simple sprite kit game that will position a player on the left side of the screen, while enemies approach from the right. Since the player can be moved up and down, I want the enemies to "smartly" adjust their path towards the player.
I tried removing and re-adding the SKAction sequence whenever the player moves, but the below code causes the enemies to not show at all, probably because its just adding and removing each action on every frame update, so they never have a chance to move.
Hoping to get a little feedback about the best practice of creating "smart" enemies that will move towards a player's position at any time.
Here is my code:
func moveEnemy(enemy: Enemy) {
let moveEnemyAction = SKAction.moveTo(CGPoint(x:self.player.position.x, y:self.player.position.y), duration: 1.0)
moveEnemyAction.speed = 0.2
let removeEnemyAction = SKAction.removeFromParent()
enemy.runAction(SKAction.sequence([moveEnemyAction,removeEnemyAction]), withKey: "moveEnemyAction")
}
func updateEnemyPath() {
for enemy in self.enemies {
if let action = enemy.actionForKey("moveEnemyAction") {
enemy.removeAllActions()
self.moveEnemy(enemy)
}
}
}
override func update(currentTime: NSTimeInterval) {
self. updateEnemyPath()
}
You have to update enemy position and zRotation property in each update: method call.
Seeker and a Target
Okay, so lets add some nodes to the scene. We need a seeker and a target. Seeker would be a missile, and target would be a touch location. I said you should do this inside of a update: method, but I will use touchesMoved method to make a better example. Here is how you should setup the scene:
import SpriteKit
class GameScene: SKScene, SKPhysicsContactDelegate {
let missile = SKSpriteNode(imageNamed: "seeking_missile")
let missileSpeed:CGFloat = 3.0
override func didMoveToView(view: SKView) {
missile.position = CGPoint(x: frame.midX, y: frame.midY)
addChild(missile)
}
}
Aiming
To implement the aiming you have to calculate the how much you have to rotate a sprite based on its target. In this example I will use a missile and make it point towards the touch location. To accomplish this, you should use atan2 function, like this ( inside touchesMoved: method):
if let touch = touches.first {
let location = touch.locationInNode(self)
//Aim
let dx = location.x - missile.position.x
let dy = location.y - missile.position.y
let angle = atan2(dy, dx)
missile.zRotation = angle
}
Note that atan2 accepts parameters in y,x order, rather than x,y.
So right now, we have an angle in which missile should go. Now lets update its position based on that angle (add this inside touchesMoved: method right below the aiming part):
//Seek
let vx = cos(angle) * missileSpeed
let vy = sin(angle) * missileSpeed
missile.position.x += vx
missile.position.y += vy
And that would be it. Here is the result:
Note that in Sprite-Kit the angle of 0 radians specifies the positive x axis. And the positive angle is in the counterclockwise direction:
Read more here.
This means that you should orient your missile to the right rather than upwards . You can use the upwards oriented image as well, but you will have to do something like this:
missile.zRotation = angle - CGFloat(M_PI_2)
I'm trying to move SKSpriteNode horizontally by dragging. To get the idea of what I try to achieve you can watch this. I want player to be able to drag sprite without touching it. But I don't really know how to implement it correctly.
I tried to do something like:
override func didMoveToView(view: SKView) {
/* Setup your scene here */
capLeft.size = self.capLeft.size
self.capLeft.position = CGPointMake(CGRectGetMinX(self.frame) + self.capLeft.size.height * 2, CGRectGetMinY(self.frame) + self.capLeft.size.height * 1.5)
capLeft.zPosition = 1
self.addChild(capLeft)
let panLeftCap: UIPanGestureRecognizer = UIPanGestureRecognizer(target: capLeft, action: Selector("moveLeftCap:"))
And when I'm setting a moveLeftCap function, code that I've found for UIPanGestureRecognizer is requiring "View" and gives me an error. I also wanted to limit min and max positions of a sprite through which it shouldn't go.
Any ideas how to implement that?
You probably get that error because you can't just access the view from any node in the tree. You could to refer to it as scene!.view or you handle the gesture within you scene instead which is preferable if you want to keep things simple.
I gave it a try and came up with this basic scene:
import SpriteKit
class GameScene: SKScene {
var shape:SKNode!
override func didMoveToView(view: SKView) {
//creates the shape to be moved
shape = SKShapeNode(circleOfRadius: 30.0)
shape.position = CGPointMake(frame.midX, frame.midY)
addChild(shape)
//sets up gesture recognizer
let pan = UIPanGestureRecognizer(target: self, action: "panned:")
view.addGestureRecognizer(pan)
}
var previousTranslateX:CGFloat = 0.0
func panned (sender:UIPanGestureRecognizer) {
//retrieve pan movement along the x-axis of the view since the gesture began
let currentTranslateX = sender.translationInView(view!).x
//calculate translation since last measurement
let translateX = currentTranslateX - previousTranslateX
//move shape within frame boundaries
let newShapeX = shape.position.x + translateX
if newShapeX < frame.maxX && newShapeX > frame.minX {
shape.position = CGPointMake(shape.position.x + translateX, shape.position.y)
}
//(re-)set previous measurement
if sender.state == .Ended {
previousTranslateX = 0
} else {
previousTranslateX = currentTranslateX
}
}
}
when you move you finger across the screen, the circle gets moves along the x-axis accordingly.
if you want to move the sprite in both x and y directions, remember to invert the y-values from the view (up in view is down in scene).
I am creating a Terraria-style game in Swift. I want to have it so the player node is always in the center of the screen, and when you move right the blocks go left like in Terraria.
I am currently trying to figure out how to keep the view centered on the character. Does anyone know of a good way of accomplishing this?
Since iOS 9 / OS X 10.11 / tvOS, SpriteKit includes SKCameraNode, which makes a lot of this easier:
positioning the camera node automatically adjusts the viewport
you can easily rotate/zoom the camera by transform in the camera node
you can fix HUD elements relative to the screen by making them children of the camera node
the scene's position stays fixed, so things like physics joints don't break the way they do when you emulate a camera by moving the world
It gets even better when you combine camera nodes with another new feature, SKConstraint. You can use a constraint to specify that the camera's position is always centered on a character... or add extra constraints to say, for example, that the camera's position must stay within some margin of the edge of the world.
The below will center the camera on a specific node. It can also smoothly transition to the new position over a set time frame.
class CameraScene : SKScene {
// Flag indicating whether we've setup the camera system yet.
var isCreated: Bool = false
// The root node of your game world. Attach game entities
// (player, enemies, &c.) to here.
var world: SKNode?
// The root node of our UI. Attach control buttons & state
// indicators here.
var overlay: SKNode?
// The camera. Move this node to change what parts of the world are visible.
var camera: SKNode?
override func didMoveToView(view: SKView) {
if !isCreated {
isCreated = true
// Camera setup
self.anchorPoint = CGPoint(x: 0.5, y: 0.5)
self.world = SKNode()
self.world?.name = "world"
addChild(self.world)
self.camera = SKNode()
self.camera?.name = "camera"
self.world?.addChild(self.camera)
// UI setup
self.overlay = SKNode()
self.overlay?.zPosition = 10
self.overlay?.name = "overlay"
addChild(self.overlay)
}
}
override func didSimulatePhysics() {
if self.camera != nil {
self.centerOnNode(self.camera!)
}
}
func centerOnNode(node: SKNode) {
let cameraPositionInScene: CGPoint = node.scene.convertPoint(node.position, fromNode: node.parent)
node.parent.position = CGPoint(x:node.parent.position.x - cameraPositionInScene.x, y:node.parent.position.y - cameraPositionInScene.y)
}
}
Change what’s visible in the world by moving the camera:
// Lerp the camera to 100, 50 over the next half-second.
self.camera?.runAction(SKAction.moveTo(CGPointMake(100, 50), duration: 0.5))
Source: swiftalicio - 2D Camera in SpriteKit
For additional information, look at Apple's SpriteKit Programming Guide (Example: Centering the Scene on a Node).
You have to create World node that contains nodes. And you should put anchorPoint for example (0.5,0.5). Center on your player. And then you should move your player.
func centerOnNode(node:SKNode){
let cameraPositionInScene:CGPoint = self.convertPoint(node.position, fromNode: world!)
world!.position = CGPoint(x:world!.position.x - cameraPositionInScene.x, y: world!.position.y - cameraPositionInScene.y)
}
override func didSimulatePhysics() {
self.centerOnNode(player!)
}