本文介绍了用SKScene和SKActions替换CALayer和CABasicAnimation的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我正在尝试对Metaballs上的
更新（此部分开始模拟静态球和动态球的运动左右，但没有元球动画）
类GameScene：SKScene {
var dBCircle：SKShapeNode！
let radiusDBCircle：CGFloat = 10
let radiusBall：CGFloat = 15
private let SCALE_RATE：CGFloat = 0.3
覆盖func didMoveToView（view：SKView）{
//一些参数
let strokeColor = SKColor.orangeColor（）
dBHeight = CGRectGetMaxY（self.frame）-84 // 64 navigationController高度+ 20合理距离
let dBStartX = CGRectGetMidX（self.frame ）-160 //最左端
让dBStopX = CGRectGetMidX（self.frame）+160 //最右端
让dBWidth = dBStopX-dBStartX
let totalBalls = 7 //第一个和最后一个将被隐藏
let ballArea = dBWidth / CGFloat（totalBalls-1）
let distanceBtwBalls =（（ballArea-（radiusBall * 2））+ radiusBall * 2）
//创建dbCircle
dBCircle = SKShapeNode.init（circleOfRadius：radiusDBCircle）
dBCircle.position = CGPointMake（CGRectGetMidX（self.frame），dBHeight）
dBCircle.strokeCo lor = strokeColor
dBCircle.name = dBCircle
dBCircle.fillColor = UIColor.clearColor（）
addChild（dBCircle）
//为我制作静态球
in 0 ..< totalBalls {
let ball = SKShapeNode.init（circleOfRadius：radiusBall）
ball.position = CGPointMake（dBStartX +（distanceBtwBalls * CGFloat（i）），dBHeight）
球.strokeColor = strokeColor
ball.name = ball
ball.fillColor = UIColor.clearColor（）
如果i == 0 || i == totalBalls-1 {
ball.hidden = true
}
addChild（ball）
}
mediaTimingFunctionEaseInEaseOutEmulate（dBCircle，dBStartX：dBStartX，dBStopX：dBStopX）
}
func mediaTimingFunctionEaseInEaseOutEmulate（node：SKShapeNode，dBStartX：CGFloat，dBStopX：CGFloat）{
let actionMoveLeft = SKAction.moveToX（dBStartX，持续时间：1.7）
actionMoveLeft.timingMode = SKActionTimingMode.EaseInEaseOut
let actionMoveRight = SKAction.moveToX（dBStopX，持续时间：1.7）
actionMoveRight.timingMode = SKActionTimingMode.EaseInEaseOut
node.runAction（SKAction.repeatActionForever （SKAction.sequence（[actionMoveLeft，actionMoveRight]）））
}
覆盖func update（currentTime：NSTimeInterval）{
var i = 0
self.enumerateChildNodesWithName（ ball ）{
节点，停在
中，让ball =节点为！ SKShapeNode
如果CGRectContainsRect（ball.frame，self.dBCircle.frame）{
if（ball.actionForKey（ zoom）== nil）{
让zoomIn = SKAction .scaleTo（1.5，持续时间：0.25）
let zoomOut = SKAction.scaleTo（1.0，持续时间：0.25）
let seq = SKAction.sequence（[zoomIn，zoomOut]）
ball.runAction （seq，withKey： zoom）
}
}
i + = 1
}
}
}
带有元球动画的新更新：
最后我已经意识到了这一结果，我的目标是使其与原始版本非常相似：
是否可以对时间进行一些更改（例如zoomIn或zoo mOut时间值或actionMoveLeft，actionMoveRight时间值），这是代码：
import SpriteKit
类GameScene：SKScene {
var dBCircle：SKShapeNode！
let radiusDBCircle：CGFloat = 10
let radiusBall：CGFloat = 15
private let SCALE_RATE：CGFloat = 0.3
覆盖func didMoveToView（view：SKView）{
//一些参数
let strokeColor = SKColor.orangeColor（）
dBHeight = CGRectGetMaxY（self.frame）-84 // 64 navigationController高度+ 20合理距离
let dBStartX = CGRectGetMidX（self.frame ）-160 //最左端
let dBStopX = CGRectGetMidX（self.frame）+160 //最右端
let dBWidth = dBStopX-dBStartX
let totalBalls = 7 //第一个和最后一个will被隐藏
let ballArea = dBWidth / CGFloat（totalBalls-1）
let distanceBtwBalls =（（ballArea-（radiusBall * 2））+ radiusBall * 2）
//创建dbCircle
dBCircle = SKShapeNode.init（circleOfRadius：radiusDBCircle）
dBCircle.position = CGPointMake（CGRectGetMidX（self.frame，dBHeight）
dBCircle.strokeCo lor = strokeColor
dBCircle.name = dBCircle
dBCircle.fillColor = UIColor.clearColor（）
addChild（dBCircle）
//为我制作静态球
in 0 ..< totalBalls {
let ball = SKShapeNode.init（circleOfRadius：radiusBall）
ball.position = CGPointMake（dBStartX +（distanceBtwBalls * CGFloat（i）），dBHeight）
球.strokeColor = strokeColor
ball.name = ball
ball.fillColor = UIColor.clearColor（）
如果i == 0 || i == totalBalls-1 {
ball.hidden = true
}
addChild（ball）
}
mediaTimingFunctionEaseInEaseOutEmulate（dBCircle，dBStartX：dBStartX，dBStopX：dBStopX）
}
func mediaTimingFunctionEaseInEaseOutEmulate（node：SKShapeNode，dBStartX：CGFloat，dBStopX：CGFloat）{
let actionMoveLeft = SKAction.moveToX（dBStartX，duration：2.5）
actionMoveLeft.timingMode = SKActionTimingMode.EaseInEaseOut
let actionMoveRight = SKAction.moveToX（dBStopX，持续时间：2.5）
actionMoveRight.timingMode = SKActionTimingMode.EaseInEaseOut
node.runAction（SKAction.repeatActionForever （SKAction.sequence（[actionMoveLeft，actionMoveRight]）））
}
// MARK：-_metaball原始函数
func _metaball（circle2：SKShapeNode，circle1：SKShapeNode，v：CGFloat，handeLenRate ：CGFloat，maxDistance：CGFloat，vanishingTime：NSTimeInterval = 0.015）{
let center1 = circle1.position
let center2 = circle2.position
let d = center1.distance（center2）
var radius1 = radiusDBCircle
var radius2 = radiusBall
如果（radius1 == 0 || radius2 == 0）{
return
}
var u1：CGFloat = 0.0
var u2：CGFloat = 0.0
if（d> maxDistance || d< ; = abs（radius1-radius2））{
return
}否则if（d u1 = acos（（radius1 * radius1 + d * d-radius2 * radius2）/（2 * radius1 * d））
u2 = acos（（radius2 * radius2 + d * d-radius1 * radius1）/（2 * radius2 * d））
} else {
u1 = 0.0
u2 = 0.0
}
let angle1 = center1.angleBetween（center2）
let angle2 = acos（（radius1-radius2）/ d）
let angle1a =角度1 + u1 +（angle2-u1）* v
let angle1b =角度1-u1-（angle2-u1）* v
let angle2a =角度1 + CGFloat（M_PI）-u2-（ CGFloat（M_PI）-u2-angle2）* v
让angle2b = angle1-CGFloat（M_PI）+ u2 +（CGFloat（M_PI）-u2-angle2）* v
让p1a = center1.po int（弧度：angle1a，withLength：radius1）
let p1b = center1.point（弧度：angle1b，withLength：radius1）
let p2a = center2.point（弧度：angle2a，withLength：radius2）
let p2b = center2.point（弧度：angle2b，withLength：radius2）
let totalRadius = radius1 + radius2
var d2 = min（v * handeLenRate，p1a.minus（p2a）.length（） / totalRadius）
d2 * = min（1，d * 2 / totalRadius）
radius1 * = d2
radius2 * = d2
let cp1a = p1a.point（弧度：angle1a -CGFloat（M_PI_2），withLength：radius1）
let cp2a = p2a.point（radians：angle2a + CGFloat（M_PI_2），withLength：radius2）
let cp2b = p2b.point（radians：angle2b-CGFloat （M_PI_2），withLength：radius2）
let cp1b = p1b.point（弧度：angle1b + CGFloat（M_PI_2），withLength：radius1）
let pathJoinedCircles = UIBezierPath（）
pathJoinedCircles.moveToPoint（ p1a）
pathJoinedCircles.a ddCurveToPoint（p2a，controlPoint1：cp1a，controlPoint2：cp2a）
pathJoinedCircles.addLineToPoint（p2b）
pathJoinedCircles.addCurveToPoint（p1b，controlPoint1：cp2b，controlPoint2：cp1b）
pathJoined
pathJoinedCircles.closePath（）
let shapeNode = SKShapeNode（路径：pathJoinedCircles.CGPath）
shapeNode.strokeColor = SKColor.orangeColor（）
shapeNode.fillColor = UIColor.clearColor（）
addChild（shapeNode）
let wait = SKAction.waitForDuration（vanishingTime）
self.runAction（wait，completion：{
shapeNode.removeFromParent（）
}）
}
覆盖功能更新（当前时间：NSTimeInterval）{
var i = 0
self.enumerateChildNodesWithName（ ball）{
节点，在
中停止让ball =节点为！ SKShapeNode
让expandFrame = CGRectMake（ball.frame.origin.x-self.radiusBall * 3，ball.frame.origin.y，ball.frame.width +（self.radiusBall * 6），ball.frame.height ）
如果CGRectContainsRect（enlargeFrame，self.dBCircle.frame）{
if（ball.actionForKey（ zoom）== nil）{
让zoomIn = SKAction.scaleTo（1.5，持续时间：0.25）
zoomIn.timingMode = SKActionTimingMode.EaseInEaseOut
let zoomOut = SKAction.scaleTo（1.0，持续时间：0.25）
let wait = SKAction.waitForDuration（0.8）
seq = SKAction.sequence（[zoomIn，zoomOut，wait]）
ball.runAction（seq，withKey： zoom）
}
}
self._metaball（ball，circle1 ：self.dBCircle，v：0.6，handeLenRate：2.0，maxDistance：4 * self.radiusBall）
i + = 1
}
}
}
// MARK ：-扩展
分机ension CGPoint {
函数距离（点：CGPoint）-> CGFloat {
let dx = point.x-self.x
let dy = point.y-self.y
return sqrt（dx * dx + dy * dy）
}
func angleBetween（point：CGPoint）-> CGFloat {
return atan2（point.y-self.y，point.x-self.x）
}
func point（弧度弧度：CGFloat，长度长度：CGFloat）-> CGPoint {
return CGPoint（x：self.x + length * cos（radians），y：self.y + length * sin（radians））
}
func minus（point：CGPoint ）-> CGPoint {
return CGPoint（x：self.x-point.x，y：self.y-point.y）
}
func length（）-> CGFloat {
return sqrt（self.x * self.x + self.y + self.y）
}
}
Swift 3：
（我对 max做了一些改动：4 * self.radiusBall 与 maxDistance：5 * self.radiusBall 变得更接近原始版本，但您可以根据需要进行更改）
import SpriteKit
class GameScene：SKScene {
var dBCircle：SKShapeNode！
let radiusDBCircle：CGFloat = 10
let radiusBall：CGFloat = 15
private let SCALE_RATE：CGFloat = 0.3
覆盖func didMove（查看：SKView）{
let标签= self.childNode（withName： // helloLabel）为？ SKLabelNode
label？.removeFromParent（）
self.anchorPoint = CGPoint.zero
//一些参数
让strokeColor = SKColor.orange
让dBHeight = self.frame .midY
让dBStartX = self.frame.midX-260 //极左
让dBStopX = self.frame.midX + 260 //极右
让dBWidth = dBStopX-dBStartX
let totalBalls = 7 //将隐藏第一个和最后一个
let ballArea = dBWidth / CGFloat（totalBalls-1）
let distanceBtwBalls =（（（ballArea-（radiusBall * 2））+ radiusBall * 2 ）
//创建dbCircle
dBCircle = SKShapeNode.init（circleOfRadius：radiusDBCircle）
dBCircle.position = CGPoint（x：self.frame.midX，y：dBHeight）
dBCircle.strokeColor =笔触颜色
dBCircle.name = dBCircle
dBCircle.fillColor = UIColor.clear
addChild（dBCircle）
//创建静态球
代表我0 ..< totalBalls {
let ball = SKShapeNode.init（circleOfRadius：radiusBall）
ball.position = CGPoint（x：dBStartX +（distanceBtwBalls * CGFloat（i）），y：dBHeight）
ball.strokeColor = strokeColor
ball.name = ball
ball.fillColor = UIColor.clear
如果i == 0 || i == totalBalls-1 {
ball.isHidden = true
}
addChild（ball）
}
mediaTimingFunctionEaseInEaseOutEmulate（node：dBCircle，dBStartX：dBStartX，dBStopX： dBStopX）
}
func mediaTimingFunctionEaseInEaseOutEmulate（node：SKShapeNode，dBStartX：CGFloat，dBStopX：CGFloat）{
let actionMoveLeft = SKAction.moveTo（x：dBStartX，持续时间：2.5）
actionMoveLeft.timingMode = SKActionTimingMode.easeInEaseOut
let actionMoveRight = SKAction.moveTo(x: dBStopX, duration:2.5)
actionMoveRight.timingMode = SKActionTimingMode.easeInEaseOut
node .run(SKAction.repeatForever(SKAction.sequence([actionMoveLeft,actionMoveRight])))
}
//MARK: - _metaball original function
func _metaball(circle2:SKShapeNode, circle1:SKShapeNode , v: CGFloat, handeLenRate: CGFloat, maxDistance: CGFloat,vanishingTime : TimeInterval = 0.015) {
le t center1 = circle1.position
let center2 = circle2.position
let d = center1.distance(point: center2)
var radius1 = radiusDBCircle
var radius2 = radiusBall
if (radius1 == 0 || radius2 == 0) {
return
}
var u1: CGFloat = 0.0
var u2: CGFloat = 0.0
if (d > maxDistance || d <= abs(radius1 - radius2)) {
return
} else if (d < radius1 + radius2) {
u1 = acos((radius1 * radius1 + d * d - radius2 * radius2) / (2 * radius1 * d))
u2 = acos((radius2 * radius2 + d * d - radius1 * radius1) / (2 * radius2 * d))
} else {
u1 = 0.0
u2 = 0.0
}
let angle1 = center1.angleBetween(point: center2)
let angle2 = acos((radius1 - radius2) / d)
let angle1a = angle1 + u1 + (angle2 - u1) * v
let angle1b = angle1 - u1 - (angle2 - u1) * v
let angle2a = angle1 + CGFloat(M_PI) - u2 - (CGFloat(M_PI) - u2 - angle2) * v
let angle2b = angle1 - CGFloat(M_PI) + u2 + (CGFloat(M_PI) - u2 - angle2) * v
let p1a = cen ter1.point(radians: angle1a, withLength: radius1)
let p1b = center1.point(radians: angle1b, withLength: radius1)
let p2a = center2.point(radians: angle2a, withLength: radius2)
let p2b = center2.point(radians: angle2b, withLength: radius2)
let totalRadius = radius1 + radius2
var d2 = min(v * handeLenRate, p1a.minus(point: p2a).length() / totalRadius)
d2 *= min(1, d * 2 / totalRadius)
radius1 *= d2
radius2 *= d2
let cp1a = p1a.point(radians: angle1a - CGFloat(M_PI_2), withLength: radius1)
let cp2a = p2a.point(radians: angle2a + CGFloat(M_PI_2), withLength: radius2)
let cp2b = p2b.point(radians: angle2b - CGFloat(M_PI_2), withLength: radius2)
let cp1b = p1b.point(radians: angle1b + CGFloat(M_PI_2), withLength: radius1)
let pathJoinedCircles = UIBezierPath()
pathJoinedCircles.move(to: p1a)
pathJoin edCircles.addCurve(to: p2a, controlPoint1: cp1a, controlPoint2: cp2a)
pathJoinedCircles.addLine(to: p2b)
pathJoinedCircles.addCurve(to: p1b, controlPoint1: cp2b, controlPoint2: cp1b)
pathJoinedCircles.addLine(to: p1a)
pathJoinedCircles.close()
let shapeNode = SKShapeNode(path: pathJoinedCircles.cgPath)
shapeNode.strokeColor = SKColor.orange
shapeNode.fillColor = UIColor.clear
addChild(shapeNode)
let wait = SKAction.wait(forDuration: vanishingTime)
self.run(wait,completion: {
shapeNode.removeFromParent()
})
}
override func update(_ currentTime: TimeInterval) {
var i = 0
self.enumerateChildNodes(withName: \"ball\") {
node, stop in
let ball = node as! SKShapeNode
let enlargeFrame = CGRect(x:ball.frame.origin.x-self.radiusBall*3,y:ball.frame.origin.y,width:ball.frame.width+(self.radiusBall*6),height:ball.frame.height)
if enlargeFrame.contains(self.dBCircle.frame) {
if (ball.action(forKey: \"zoom\") == nil) {
let zoomIn = SKAction.scale(to: 1.5, duration: 0.25)
zoomIn.timingMode = SKActionTimingMode.easeInEaseOut
let zoomOut = SKAction.scale(to: 1.0, duration: 0.25)
let wait = SKAction.wait(forDuration: 0.7)
let seq = SKAction.sequence([zoomIn,zoomOut,wait])
ball.run(seq,withKey: \"zoom\")
}
}
self._metaball(circle2: ball, circle1: self.dBCircle, v: 0.6, handeLenRate: 2.0, maxDistance: 5 * self.radiusBall)
i += 1
}
}
}
//MARK: - Extens ions
extension CGPoint {
func distance(point: CGPoint) -> CGFloat {
let dx = point.x - self.x
let dy = point.y - self.y
return sqrt(dx * dx + dy * dy)
}
func angleBetween(point: CGPoint) -> CGFloat {
return atan2(point.y - self.y, point.x - self.x)
}
func point(radians: CGFloat, withLength length: CGFloat) -> CGPoint {
return CGPoint(x: self.x + length * cos(radians), y: self.y + length * sin(radians))
}
func minus(point: CGPoint) -> CGPoint {
return CGPoint(x: self.x - point.x, y: self.y - point.y)
}
func length() -> CGFloat {
return sqrt(self.x * self.x + self.y + self.y)
}
}
I am trying to restructure this Github Swift project on Metaballs so that the circles are represented by SKShapeNodes that are moved around by SKActions instead of CABasicAnimation.
I am not interested in the various Metaball parameters (the handleLenRate, Spacing and so on) appearing in the viewController. I basically want to be able to specify a start and end position for the animation using SKActions.
I am not certain how to achieve this, especially how to replace the startAnimation function below with SKShapeNode's with SKActions:
func startAnimation() {
let loadingLayer = self.layer as! DBMetaballLoadingLayer
loadingAnimation = CABasicAnimation(keyPath: "movingBallCenterX")
loadingAnimation!.duration = 2.5
loadingAnimation!.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
loadingAnimation!.fromValue = NSValue(CGPoint:fromPoint)
loadingAnimation!.toValue = NSValue(CGPoint: toPoint)
loadingAnimation!.repeatCount = Float.infinity
loadingAnimation!.autoreverses = true
loadingLayer.addAnimation(loadingAnimation!, forKey: "loading")
}
Please see what I've been able to do below:
MBCircle class:
struct MBCircle {
var center: CGPoint = CGPointZero
var radius: CGFloat = 0.0
var frame: CGRect {
get {
return CGRect(x: center.x - radius, y: center.y - radius, width: 2 * radius, height: 2 * radius)
}
}
}
struct DefaultConfig {
static let radius: CGFloat = 15.0
static let mv: CGFloat = 0.6
static let maxDistance: CGFloat = 10 * DefaultConfig.radius
static let handleLenRate: CGFloat = 2.0
static let spacing: CGFloat = 160.0
}
GameScene class (representing both the DBMetaballLoadingLayer and DBMetaballLoadingView):
class GameScene: SKScene {
private let MOVE_BALL_SCALE_RATE: CGFloat = 0.75
private let ITEM_COUNT = 2
private let SCALE_RATE: CGFloat = 1.0//0.3
private var circlePaths = [MBCircle]()
var radius: CGFloat = DefaultConfig.radius
var maxLength: CGFloat {
get {
return (radius * 4 + spacing) * CGFloat(ITEM_COUNT)
}
}
var maxDistance: CGFloat = DefaultConfig.maxDistance
var mv: CGFloat = DefaultConfig.mv
var spacing: CGFloat = DefaultConfig.spacing {
didSet {
_adjustSpacing(spacing)
}
}
var handleLenRate: CGFloat = DefaultConfig.handleLenRate
var movingBallCenterX : CGFloat = 0.0 {
didSet {
if (circlePaths.count > 0) {
circlePaths[0].center = CGPoint(x: movingBallCenterX, y: circlePaths[0].center.y)
}
}
}
func _generalInit() {
circlePaths = Array(0..<ITEM_COUNT).map { i in
var circlePath = MBCircle()
circlePath.center = CGPoint(x: (radius * 10 + spacing) * CGFloat(i), y: radius * (1.0 + SCALE_RATE))
circlePath.radius = i == 0 ? radius * MOVE_BALL_SCALE_RATE : radius
circlePath.sprite = SKShapeNode(circleOfRadius: circlePath.radius)
circlePath.sprite?.position = circlePath.center
circlePath.sprite?.fillColor = UIColor.blueColor()
addChild(circlePath.sprite!)
return circlePath
}
}
func _adjustSpacing(spacing: CGFloat) {
if (ITEM_COUNT > 1 && circlePaths.count > 1) {
for i in 1..<ITEM_COUNT {
var circlePath = circlePaths[i]
circlePath.center = CGPoint(x: (radius*2 + spacing) * CGFloat(i), y: radius * (1.0 + SCALE_RATE))
}
}
}
func _renderPath(path: UIBezierPath) {
var shapeNode = SKShapeNode()
shapeNode.path = path.CGPath
shapeNode.fillColor = UIColor.blueColor()
addChild(shapeNode)
}
func _metaball(j: Int, i: Int, v: CGFloat, handeLenRate: CGFloat, maxDistance: CGFloat) {
let circle1 = circlePaths[i]
let circle2 = circlePaths[j]
let center1 = circle1.center
let center2 = circle2.center
let d = center1.distance(center2)
var radius1 = circle1.radius
var radius2 = circle2.radius
if (d > maxDistance) {
_renderPath(UIBezierPath(ovalInRect: circle2.frame))
} else {
let scale2 = 1 + SCALE_RATE * (1 - d / maxDistance)
radius2 *= scale2
_renderPath(UIBezierPath(ovalInRect: CGRect(x: circle2.center.x - radius2, y: circle2.center.y - radius2, width: 2 * radius2, height: 2 * radius2)))
}
if (radius1 == 0 || radius2 == 0) {
return
}
var u1: CGFloat = 0.0
var u2: CGFloat = 0.0
if (d > maxDistance || d <= abs(radius1 - radius2)) {
return
} else if (d < radius1 + radius2) {
u1 = acos((radius1 * radius1 + d * d - radius2 * radius2) / (2 * radius1 * d))
u2 = acos((radius2 * radius2 + d * d - radius1 * radius1) / (2 * radius2 * d))
} else {
u1 = 0.0
u2 = 0.0
}
let angle1 = center1.angleBetween(center2)
let angle2 = acos((radius1 - radius2) / d)
let angle1a = angle1 + u1 + (angle2 - u1) * v
let angle1b = angle1 - u1 - (angle2 - u1) * v
let angle2a = angle1 + CGFloat(M_PI) - u2 - (CGFloat(M_PI) - u2 - angle2) * v
let angle2b = angle1 - CGFloat(M_PI) + u2 + (CGFloat(M_PI) - u2 - angle2) * v
let p1a = center1.point(radians: angle1a, withLength: radius1)
let p1b = center1.point(radians: angle1b, withLength: radius1)
let p2a = center2.point(radians: angle2a, withLength: radius2)
let p2b = center2.point(radians: angle2b, withLength: radius2)
let totalRadius = radius1 + radius2
var d2 = min(v * handeLenRate, p1a.minus(p2a).length() / totalRadius)
d2 *= min(1, d * 2 / totalRadius)
radius1 *= d2
radius2 *= d2
let cp1a = p1a.point(radians: angle1a - CGFloat(M_PI_2), withLength: radius1)
let cp2a = p2a.point(radians: angle2a + CGFloat(M_PI_2), withLength: radius2)
let cp2b = p2b.point(radians: angle2b - CGFloat(M_PI_2), withLength: radius2)
let cp1b = p1b.point(radians: angle1b + CGFloat(M_PI_2), withLength: radius1)
let pathJoinedCircles = UIBezierPath()
pathJoinedCircles.moveToPoint(p1a)
pathJoinedCircles.addCurveToPoint(p2a, controlPoint1: cp1a, controlPoint2: cp2a)
pathJoinedCircles.addLineToPoint(p2b)
pathJoinedCircles.addCurveToPoint(p1b, controlPoint1: cp2b, controlPoint2: cp1b)
pathJoinedCircles.addLineToPoint(p1a)
pathJoinedCircles.closePath()
_renderPath(pathJoinedCircles)
}
func startAnimation() {
}
override func didMoveToView(view: SKView) {
_generalInit()
}
override func update(currentTime: CFTimeInterval) {
/* Called before each frame is rendered */
}
}
I didn't make any changes to the CGPointExtension class.
UPDATE
I am still trying to get the metaball effect, this is my progress so far based on suggestions from Alessandro Ornano:
import SpriteKit
extension CGPoint {
func distance(point: CGPoint) -> CGFloat {
let dx = point.x - self.x
let dy = point.y - self.y
return sqrt(dx * dx + dy * dy)
}
func angleBetween(point: CGPoint) -> CGFloat {
return atan2(point.y - self.y, point.x - self.x)
}
func point(radians radians: CGFloat, withLength length: CGFloat) -> CGPoint {
return CGPoint(x: self.x + length * cos(radians), y: self.y + length * sin(radians))
}
func minus(point: CGPoint) -> CGPoint {
return CGPoint(x: self.x - point.x, y: self.y - point.y)
}
func length() -> CGFloat {
return sqrt(self.x * self.x + self.y + self.y)
}
}
class GameScene: SKScene {
var dBCircle : SKShapeNode!
let radiusDBCircle: CGFloat = 10
let radiusBall: CGFloat = 15
var balls = [SKShapeNode]()
var distanceBtwBalls : CGFloat = 15
private let SCALE_RATE: CGFloat = 0.3
override func didMoveToView(view: SKView) {
// Some parameters
let strokeColor = SKColor.orangeColor()
let dBHeight = CGRectGetMaxY(self.frame)-84 // 64 navigationController height + 20 reasonable distance
let dBStartX = CGRectGetMidX(self.frame)-160 // extreme left
let dBStopX = CGRectGetMidX(self.frame)+160 // extreme right
let dBWidth = dBStopX - dBStartX
let totalBalls = 7 // first and last will be hidden
let ballArea = dBWidth / CGFloat(totalBalls-1)
distanceBtwBalls = ((ballArea-(radiusBall*2))+radiusBall*2)
// Create dbCircle
dBCircle = SKShapeNode.init(circleOfRadius: radiusDBCircle)
dBCircle.position = CGPointMake(CGRectGetMidX(self.frame), dBHeight)
dBCircle.strokeColor = strokeColor
dBCircle.name = "dBCircle"
dBCircle.fillColor = UIColor.clearColor()
addChild(dBCircle)
// Make static balls
for i in 0..<totalBalls {
let ball = SKShapeNode.init(circleOfRadius: radiusBall)
ball.position = CGPointMake(dBStartX+(distanceBtwBalls*CGFloat(i)), dBHeight)
ball.strokeColor = strokeColor
ball.name = "ball"
ball.fillColor = UIColor.clearColor()
balls.append(ball)
if i == 0 || i == totalBalls-1 {
ball.hidden = true
}
addChild(ball)
}
mediaTimingFunctionEaseInEaseOutEmulate(dBCircle,dBStartX: dBStartX,dBStopX: dBStopX)
}
func mediaTimingFunctionEaseInEaseOutEmulate(node:SKShapeNode,dBStartX:CGFloat,dBStopX:CGFloat) {
let actionMoveLeft = SKAction.moveToX(dBStartX, duration:1.7)
actionMoveLeft.timingMode = SKActionTimingMode.EaseInEaseOut
let actionMoveRight = SKAction.moveToX(dBStopX, duration:1.7)
actionMoveRight.timingMode = SKActionTimingMode.EaseInEaseOut
node.runAction(SKAction.repeatActionForever(SKAction.sequence([actionMoveLeft,actionMoveRight])))
}
override func update(currentTime: NSTimeInterval) {
var i = 0
self.enumerateChildNodesWithName("ball") {
node, stop in
let ball = node as! SKShapeNode
if CGRectContainsRect(ball.frame, self.dBCircle.frame) {
if (ball.actionForKey("zoom") == nil) {
let zoomIn = SKAction.scaleTo(1.5, duration: 0.25)
let zoomOut = SKAction.scaleTo(1.0, duration: 0.25)
let seq = SKAction.sequence([zoomIn,zoomOut])
ball.runAction(seq,withKey: "zoom")
}
}
i += 1
}
movingBeziers()
}
func _renderPath(path: UIBezierPath) {
let shapeNode = SKShapeNode(path: path.CGPath)
shapeNode.fillColor = UIColor.blueColor()
addChild(shapeNode)
}
func movingBeziers() {
_renderPath(UIBezierPath(ovalInRect: dBCircle.frame))
for j in 1..<balls.count {
self.latestTestMetaball(j, circleShape: dBCircle, v: 0.6, handleLenRate: 2.0, maxDistance: self.distanceBtwBalls)
}
}
func latestTestMetaball (j: Int, circleShape: SKShapeNode, v: CGFloat, handleLenRate: CGFloat, maxDistance: CGFloat) {
let circle1 = circleShape
let circle2 = balls[j]
let center1 = circle1.position
let center2 = circle2.position
let d = center1.distance(center2)
var radius1 = circle1.frame.width
var radius2 = circle2.frame.width
var u1: CGFloat = 0.0
var u2: CGFloat = 0.0
if (d > maxDistance || d <= abs(radius1 - radius2)) {
return
} else if (d < radius1 + radius2) {
u1 = acos((radius1 * radius1 + d * d - radius2 * radius2) / (2 * radius1 * d))
u2 = acos((radius2 * radius2 + d * d - radius1 * radius1) / (2 * radius2 * d))
} else {
u1 = 0.0
u2 = 0.0
}
let angle1 = center1.angleBetween(center2)
let angle2 = acos((radius1 - radius2) / d)
let angle1a = angle1 + u1 + (angle2 - u1) * v
let angle1b = angle1 - u1 - (angle2 - u1) * v
let angle2a = angle1 + CGFloat(M_PI) - u2 - (CGFloat(M_PI) - u2 - angle2) * v
let angle2b = angle1 - CGFloat(M_PI) + u2 + (CGFloat(M_PI) - u2 - angle2) * v
let p1a = center1.point(radians: angle1a, withLength: radius1)
let p1b = center1.point(radians: angle1b, withLength: radius1)
let p2a = center2.point(radians: angle2a, withLength: radius2)
let p2b = center2.point(radians: angle2b, withLength: radius2)
let totalRadius = radius1 + radius2
var d2 = min(v * handleLenRate, p1a.minus(p2a).length() / totalRadius)
d2 *= min(1, d * 2 / totalRadius)
radius1 *= d2
radius2 *= d2
let cp1a = p1a.point(radians: angle1a - CGFloat(M_PI_2), withLength: radius1)
let cp2a = p2a.point(radians: angle2a + CGFloat(M_PI_2), withLength: radius2)
let cp2b = p2b.point(radians: angle2b - CGFloat(M_PI_2), withLength: radius2)
let cp1b = p1b.point(radians: angle1b + CGFloat(M_PI_2), withLength: radius1)
let pathJoinedCircles = UIBezierPath()
pathJoinedCircles.moveToPoint(p1a)
pathJoinedCircles.addCurveToPoint(p2a, controlPoint1: cp1a, controlPoint2: cp2a)
pathJoinedCircles.addLineToPoint(p2b)
pathJoinedCircles.addCurveToPoint(p1b, controlPoint1: cp2b, controlPoint2: cp1b)
pathJoinedCircles.addLineToPoint(p1a)
pathJoinedCircles.closePath()
let shapeNode = SKShapeNode(path: pathJoinedCircles.CGPath)
shapeNode.fillColor = UIColor.blueColor()
addChild(shapeNode)
}
}
解决方案
You can easily achieve this kind of animation using moveToX and the timingMode parameter.
New Swift 3 translation below at the end of this answer.
To make an example I use the Xcode Sprite-Kit "Hello, World!" official project demo:
class GameScene: SKScene {
override func didMoveToView(view: SKView) {
/* Setup your scene here */
let myLabel = SKLabelNode(fontNamed:"Chalkduster")
myLabel.text = "Hello, World!"
myLabel.fontSize = 15
myLabel.position = CGPoint(x:CGRectGetMidX(self.frame), y:CGRectGetMidY(self.frame))
self.addChild(myLabel)
mediaTimingFunctionEaseInEaseOutEmulate(myLabel)
}
func mediaTimingFunctionEaseInEaseOutEmulate(node:SKLabelNode) {
let actionMoveLeft = SKAction.moveToX(CGRectGetMidX(self.frame)-100, duration:1.5)
actionMoveLeft.timingMode = SKActionTimingMode.EaseInEaseOut
let actionMoveRight = SKAction.moveToX(CGRectGetMidX(self.frame)+100, duration:1.5)
actionMoveRight.timingMode = SKActionTimingMode.EaseInEaseOut
node.runAction(SKAction.repeatActionForever(SKAction.sequence([actionMoveLeft,actionMoveRight])))
}
}
Output:
Update (This part start to emulate the static ball and the dynamic ball moving left and right but without metaball animations)
class GameScene: SKScene {
var dBCircle : SKShapeNode!
let radiusDBCircle: CGFloat = 10
let radiusBall: CGFloat = 15
private let SCALE_RATE: CGFloat = 0.3
override func didMoveToView(view: SKView) {
// Some parameters
let strokeColor = SKColor.orangeColor()
let dBHeight = CGRectGetMaxY(self.frame)-84 // 64 navigationController height + 20 reasonable distance
let dBStartX = CGRectGetMidX(self.frame)-160 // extreme left
let dBStopX = CGRectGetMidX(self.frame)+160 // extreme right
let dBWidth = dBStopX - dBStartX
let totalBalls = 7 // first and last will be hidden
let ballArea = dBWidth / CGFloat(totalBalls-1)
let distanceBtwBalls = ((ballArea-(radiusBall*2))+radiusBall*2)
// Create dbCircle
dBCircle = SKShapeNode.init(circleOfRadius: radiusDBCircle)
dBCircle.position = CGPointMake(CGRectGetMidX(self.frame), dBHeight)
dBCircle.strokeColor = strokeColor
dBCircle.name = "dBCircle"
dBCircle.fillColor = UIColor.clearColor()
addChild(dBCircle)
// Make static balls
for i in 0..<totalBalls {
let ball = SKShapeNode.init(circleOfRadius: radiusBall)
ball.position = CGPointMake(dBStartX+(distanceBtwBalls*CGFloat(i)), dBHeight)
ball.strokeColor = strokeColor
ball.name = "ball"
ball.fillColor = UIColor.clearColor()
if i == 0 || i == totalBalls-1 {
ball.hidden = true
}
addChild(ball)
}
mediaTimingFunctionEaseInEaseOutEmulate(dBCircle,dBStartX: dBStartX,dBStopX: dBStopX)
}
func mediaTimingFunctionEaseInEaseOutEmulate(node:SKShapeNode,dBStartX:CGFloat,dBStopX:CGFloat) {
let actionMoveLeft = SKAction.moveToX(dBStartX, duration:1.7)
actionMoveLeft.timingMode = SKActionTimingMode.EaseInEaseOut
let actionMoveRight = SKAction.moveToX(dBStopX, duration:1.7)
actionMoveRight.timingMode = SKActionTimingMode.EaseInEaseOut
node.runAction(SKAction.repeatActionForever(SKAction.sequence([actionMoveLeft,actionMoveRight])))
}
override func update(currentTime: NSTimeInterval) {
var i = 0
self.enumerateChildNodesWithName("ball") {
node, stop in
let ball = node as! SKShapeNode
if CGRectContainsRect(ball.frame, self.dBCircle.frame) {
if (ball.actionForKey("zoom") == nil) {
let zoomIn = SKAction.scaleTo(1.5, duration: 0.25)
let zoomOut = SKAction.scaleTo(1.0, duration: 0.25)
let seq = SKAction.sequence([zoomIn,zoomOut])
ball.runAction(seq,withKey: "zoom")
}
}
i += 1
}
}
}
New update with metaball animation:
Finally I've realize this result, my goal is to make it very similar to the original :
is it possible to make some variations to times (for example zoomIn or zoomOut time values or actionMoveLeft, actionMoveRight time values), this is the code:
import SpriteKit
class GameScene: SKScene {
var dBCircle : SKShapeNode!
let radiusDBCircle: CGFloat = 10
let radiusBall: CGFloat = 15
private let SCALE_RATE: CGFloat = 0.3
override func didMoveToView(view: SKView) {
// Some parameters
let strokeColor = SKColor.orangeColor()
let dBHeight = CGRectGetMaxY(self.frame)-84 // 64 navigationController height + 20 reasonable distance
let dBStartX = CGRectGetMidX(self.frame)-160 // extreme left
let dBStopX = CGRectGetMidX(self.frame)+160 // extreme right
let dBWidth = dBStopX - dBStartX
let totalBalls = 7 // first and last will be hidden
let ballArea = dBWidth / CGFloat(totalBalls-1)
let distanceBtwBalls = ((ballArea-(radiusBall*2))+radiusBall*2)
// Create dbCircle
dBCircle = SKShapeNode.init(circleOfRadius: radiusDBCircle)
dBCircle.position = CGPointMake(CGRectGetMidX(self.frame), dBHeight)
dBCircle.strokeColor = strokeColor
dBCircle.name = "dBCircle"
dBCircle.fillColor = UIColor.clearColor()
addChild(dBCircle)
// Make static balls
for i in 0..<totalBalls {
let ball = SKShapeNode.init(circleOfRadius: radiusBall)
ball.position = CGPointMake(dBStartX+(distanceBtwBalls*CGFloat(i)), dBHeight)
ball.strokeColor = strokeColor
ball.name = "ball"
ball.fillColor = UIColor.clearColor()
if i == 0 || i == totalBalls-1 {
ball.hidden = true
}
addChild(ball)
}
mediaTimingFunctionEaseInEaseOutEmulate(dBCircle,dBStartX: dBStartX,dBStopX: dBStopX)
}
func mediaTimingFunctionEaseInEaseOutEmulate(node:SKShapeNode,dBStartX:CGFloat,dBStopX:CGFloat) {
let actionMoveLeft = SKAction.moveToX(dBStartX, duration:2.5)
actionMoveLeft.timingMode = SKActionTimingMode.EaseInEaseOut
let actionMoveRight = SKAction.moveToX(dBStopX, duration:2.5)
actionMoveRight.timingMode = SKActionTimingMode.EaseInEaseOut
node.runAction(SKAction.repeatActionForever(SKAction.sequence([actionMoveLeft,actionMoveRight])))
}
//MARK: - _metaball original function
func _metaball(circle2:SKShapeNode, circle1:SKShapeNode, v: CGFloat, handeLenRate: CGFloat, maxDistance: CGFloat,vanishingTime : NSTimeInterval = 0.015) {
let center1 = circle1.position
let center2 = circle2.position
let d = center1.distance(center2)
var radius1 = radiusDBCircle
var radius2 = radiusBall
if (radius1 == 0 || radius2 == 0) {
return
}
var u1: CGFloat = 0.0
var u2: CGFloat = 0.0
if (d > maxDistance || d <= abs(radius1 - radius2)) {
return
} else if (d < radius1 + radius2) {
u1 = acos((radius1 * radius1 + d * d - radius2 * radius2) / (2 * radius1 * d))
u2 = acos((radius2 * radius2 + d * d - radius1 * radius1) / (2 * radius2 * d))
} else {
u1 = 0.0
u2 = 0.0
}
let angle1 = center1.angleBetween(center2)
let angle2 = acos((radius1 - radius2) / d)
let angle1a = angle1 + u1 + (angle2 - u1) * v
let angle1b = angle1 - u1 - (angle2 - u1) * v
let angle2a = angle1 + CGFloat(M_PI) - u2 - (CGFloat(M_PI) - u2 - angle2) * v
let angle2b = angle1 - CGFloat(M_PI) + u2 + (CGFloat(M_PI) - u2 - angle2) * v
let p1a = center1.point(radians: angle1a, withLength: radius1)
let p1b = center1.point(radians: angle1b, withLength: radius1)
let p2a = center2.point(radians: angle2a, withLength: radius2)
let p2b = center2.point(radians: angle2b, withLength: radius2)
let totalRadius = radius1 + radius2
var d2 = min(v * handeLenRate, p1a.minus(p2a).length() / totalRadius)
d2 *= min(1, d * 2 / totalRadius)
radius1 *= d2
radius2 *= d2
let cp1a = p1a.point(radians: angle1a - CGFloat(M_PI_2), withLength: radius1)
let cp2a = p2a.point(radians: angle2a + CGFloat(M_PI_2), withLength: radius2)
let cp2b = p2b.point(radians: angle2b - CGFloat(M_PI_2), withLength: radius2)
let cp1b = p1b.point(radians: angle1b + CGFloat(M_PI_2), withLength: radius1)
let pathJoinedCircles = UIBezierPath()
pathJoinedCircles.moveToPoint(p1a)
pathJoinedCircles.addCurveToPoint(p2a, controlPoint1: cp1a, controlPoint2: cp2a)
pathJoinedCircles.addLineToPoint(p2b)
pathJoinedCircles.addCurveToPoint(p1b, controlPoint1: cp2b, controlPoint2: cp1b)
pathJoinedCircles.addLineToPoint(p1a)
pathJoinedCircles.closePath()
let shapeNode = SKShapeNode(path: pathJoinedCircles.CGPath)
shapeNode.strokeColor = SKColor.orangeColor()
shapeNode.fillColor = UIColor.clearColor()
addChild(shapeNode)
let wait = SKAction.waitForDuration(vanishingTime)
self.runAction(wait,completion: {
shapeNode.removeFromParent()
})
}
override func update(currentTime: NSTimeInterval) {
var i = 0
self.enumerateChildNodesWithName("ball") {
node, stop in
let ball = node as! SKShapeNode
let enlargeFrame = CGRectMake(ball.frame.origin.x-self.radiusBall*3,ball.frame.origin.y,ball.frame.width+(self.radiusBall*6),ball.frame.height)
if CGRectContainsRect(enlargeFrame, self.dBCircle.frame) {
if (ball.actionForKey("zoom") == nil) {
let zoomIn = SKAction.scaleTo(1.5, duration: 0.25)
zoomIn.timingMode = SKActionTimingMode.EaseInEaseOut
let zoomOut = SKAction.scaleTo(1.0, duration: 0.25)
let wait = SKAction.waitForDuration(0.8)
let seq = SKAction.sequence([zoomIn,zoomOut,wait])
ball.runAction(seq,withKey: "zoom")
}
}
self._metaball(ball, circle1: self.dBCircle, v: 0.6, handeLenRate: 2.0, maxDistance: 4 * self.radiusBall)
i += 1
}
}
}
//MARK: - Extensions
extension CGPoint {
func distance(point: CGPoint) -> CGFloat {
let dx = point.x - self.x
let dy = point.y - self.y
return sqrt(dx * dx + dy * dy)
}
func angleBetween(point: CGPoint) -> CGFloat {
return atan2(point.y - self.y, point.x - self.x)
}
func point(radians radians: CGFloat, withLength length: CGFloat) -> CGPoint {
return CGPoint(x: self.x + length * cos(radians), y: self.y + length * sin(radians))
}
func minus(point: CGPoint) -> CGPoint {
return CGPoint(x: self.x - point.x, y: self.y - point.y)
}
func length() -> CGFloat {
return sqrt(self.x * self.x + self.y + self.y)
}
}
Swift 3:
(I've made a little change to maxDistance: 4 * self.radiusBall with maxDistance: 5 * self.radiusBall to become more similar to the original but you can change it as you wish)
import SpriteKit
class GameScene: SKScene {
var dBCircle : SKShapeNode!
let radiusDBCircle: CGFloat = 10
let radiusBall: CGFloat = 15
private let SCALE_RATE: CGFloat = 0.3
override func didMove(to view: SKView) {
let label = self.childNode(withName: "//helloLabel") as? SKLabelNode
label?.removeFromParent()
self.anchorPoint = CGPoint.zero
// Some parameters
let strokeColor = SKColor.orange
let dBHeight = self.frame.midY
let dBStartX = self.frame.midX-260 // extreme left
let dBStopX = self.frame.midX+260 // extreme right
let dBWidth = dBStopX - dBStartX
let totalBalls = 7 // first and last will be hidden
let ballArea = dBWidth / CGFloat(totalBalls-1)
let distanceBtwBalls = ((ballArea-(radiusBall*2))+radiusBall*2)
// Create dbCircle
dBCircle = SKShapeNode.init(circleOfRadius: radiusDBCircle)
dBCircle.position = CGPoint(x:self.frame.midX, y:dBHeight)
dBCircle.strokeColor = strokeColor
dBCircle.name = "dBCircle"
dBCircle.fillColor = UIColor.clear
addChild(dBCircle)
// Make static balls
for i in 0..<totalBalls {
let ball = SKShapeNode.init(circleOfRadius: radiusBall)
ball.position = CGPoint(x:dBStartX+(distanceBtwBalls*CGFloat(i)), y:dBHeight)
ball.strokeColor = strokeColor
ball.name = "ball"
ball.fillColor = UIColor.clear
if i == 0 || i == totalBalls-1 {
ball.isHidden = true
}
addChild(ball)
}
mediaTimingFunctionEaseInEaseOutEmulate(node: dBCircle,dBStartX: dBStartX,dBStopX: dBStopX)
}
func mediaTimingFunctionEaseInEaseOutEmulate(node:SKShapeNode,dBStartX:CGFloat,dBStopX:CGFloat) {
let actionMoveLeft = SKAction.moveTo(x: dBStartX, duration:2.5)
actionMoveLeft.timingMode = SKActionTimingMode.easeInEaseOut
let actionMoveRight = SKAction.moveTo(x: dBStopX, duration:2.5)
actionMoveRight.timingMode = SKActionTimingMode.easeInEaseOut
node.run(SKAction.repeatForever(SKAction.sequence([actionMoveLeft,actionMoveRight])))
}
//MARK: - _metaball original function
func _metaball(circle2:SKShapeNode, circle1:SKShapeNode, v: CGFloat, handeLenRate: CGFloat, maxDistance: CGFloat,vanishingTime : TimeInterval = 0.015) {
let center1 = circle1.position
let center2 = circle2.position
let d = center1.distance(point: center2)
var radius1 = radiusDBCircle
var radius2 = radiusBall
if (radius1 == 0 || radius2 == 0) {
return
}
var u1: CGFloat = 0.0
var u2: CGFloat = 0.0
if (d > maxDistance || d <= abs(radius1 - radius2)) {
return
} else if (d < radius1 + radius2) {
u1 = acos((radius1 * radius1 + d * d - radius2 * radius2) / (2 * radius1 * d))
u2 = acos((radius2 * radius2 + d * d - radius1 * radius1) / (2 * radius2 * d))
} else {
u1 = 0.0
u2 = 0.0
}
let angle1 = center1.angleBetween(point: center2)
let angle2 = acos((radius1 - radius2) / d)
let angle1a = angle1 + u1 + (angle2 - u1) * v
let angle1b = angle1 - u1 - (angle2 - u1) * v
let angle2a = angle1 + CGFloat(M_PI) - u2 - (CGFloat(M_PI) - u2 - angle2) * v
let angle2b = angle1 - CGFloat(M_PI) + u2 + (CGFloat(M_PI) - u2 - angle2) * v
let p1a = center1.point(radians: angle1a, withLength: radius1)
let p1b = center1.point(radians: angle1b, withLength: radius1)
let p2a = center2.point(radians: angle2a, withLength: radius2)
let p2b = center2.point(radians: angle2b, withLength: radius2)
let totalRadius = radius1 + radius2
var d2 = min(v * handeLenRate, p1a.minus(point: p2a).length() / totalRadius)
d2 *= min(1, d * 2 / totalRadius)
radius1 *= d2
radius2 *= d2
let cp1a = p1a.point(radians: angle1a - CGFloat(M_PI_2), withLength: radius1)
let cp2a = p2a.point(radians: angle2a + CGFloat(M_PI_2), withLength: radius2)
let cp2b = p2b.point(radians: angle2b - CGFloat(M_PI_2), withLength: radius2)
let cp1b = p1b.point(radians: angle1b + CGFloat(M_PI_2), withLength: radius1)
let pathJoinedCircles = UIBezierPath()
pathJoinedCircles.move(to: p1a)
pathJoinedCircles.addCurve(to: p2a, controlPoint1: cp1a, controlPoint2: cp2a)
pathJoinedCircles.addLine(to: p2b)
pathJoinedCircles.addCurve(to: p1b, controlPoint1: cp2b, controlPoint2: cp1b)
pathJoinedCircles.addLine(to: p1a)
pathJoinedCircles.close()
let shapeNode = SKShapeNode(path: pathJoinedCircles.cgPath)
shapeNode.strokeColor = SKColor.orange
shapeNode.fillColor = UIColor.clear
addChild(shapeNode)
let wait = SKAction.wait(forDuration: vanishingTime)
self.run(wait,completion: {
shapeNode.removeFromParent()
})
}
override func update(_ currentTime: TimeInterval) {
var i = 0
self.enumerateChildNodes(withName: "ball") {
node, stop in
let ball = node as! SKShapeNode
let enlargeFrame = CGRect(x:ball.frame.origin.x-self.radiusBall*3,y:ball.frame.origin.y,width:ball.frame.width+(self.radiusBall*6),height:ball.frame.height)
if enlargeFrame.contains(self.dBCircle.frame) {
if (ball.action(forKey: "zoom") == nil) {
let zoomIn = SKAction.scale(to: 1.5, duration: 0.25)
zoomIn.timingMode = SKActionTimingMode.easeInEaseOut
let zoomOut = SKAction.scale(to: 1.0, duration: 0.25)
let wait = SKAction.wait(forDuration: 0.7)
let seq = SKAction.sequence([zoomIn,zoomOut,wait])
ball.run(seq,withKey: "zoom")
}
}
self._metaball(circle2: ball, circle1: self.dBCircle, v: 0.6, handeLenRate: 2.0, maxDistance: 5 * self.radiusBall)
i += 1
}
}
}
//MARK: - Extensions
extension CGPoint {
func distance(point: CGPoint) -> CGFloat {
let dx = point.x - self.x
let dy = point.y - self.y
return sqrt(dx * dx + dy * dy)
}
func angleBetween(point: CGPoint) -> CGFloat {
return atan2(point.y - self.y, point.x - self.x)
}
func point(radians: CGFloat, withLength length: CGFloat) -> CGPoint {
return CGPoint(x: self.x + length * cos(radians), y: self.y + length * sin(radians))
}
func minus(point: CGPoint) -> CGPoint {
return CGPoint(x: self.x - point.x, y: self.y - point.y)
}
func length() -> CGFloat {
return sqrt(self.x * self.x + self.y + self.y)
}
}
这篇关于用SKScene和SKActions替换CALayer和CABasicAnimation的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！