这是我的答案的第二稿,展示了简单精灵动画的基本功能:
class GameScene: SKScene {
// Left spin is ascending indices, right spin is descending indices.
var initialTextures = [SKTexture]()
// Reset then reload this from 0-6 with the correct image sequences from initialTextures:
var nextTextures = [SKTexture]()
var sprite = SKSpriteNode()
// Use gesture recognizer or other means to set how fast the spin should be.
var velocity = TimeInterval(0.1)
enum Direction { case left, right }
func spin(direction: Direction, timePerFrame: TimeInterval) {
nextTextures = []
for _ in 0...6 {
var index = initialTextures.index(of: sprite.texture!)
// Left is ascending, right is descending:
switch direction {
case .left:
if index == (initialTextures.count - 1) { index = 0 } else { index! += 1 }
case .right:
if index == 0 { index = (initialTextures.count - 1) } else { index! -= 1 }
}
let nextTexture = initialTextures[index!]
nextTextures.append(nextTexture)
sprite.texture = nextTexture
}
let action = SKAction.repeatForever(.animate(with: nextTextures, timePerFrame: timePerFrame))
sprite.run(action)
}
override func didMove(to view: SKView) {
removeAllChildren()
// Make our textures for spinning:
for i in 0...6 {
initialTextures.append(SKTexture(imageNamed: "img_\(i)"))
}
nextTextures = initialTextures
sprite.texture = nextTextures.first!
sprite.size = nextTextures.first!.size()
addChild(sprite)
spin(direction: .left, timePerFrame: 0.10)
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
spin(direction: .right, timePerFrame: velocity)
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
spin(direction: .left, timePerFrame: velocity)
}
}
现在您只需单击/释放以交替右左。
下一个草案的待办事项:
- 实现速度手势识别器
- 如果需要,实现衰减(因此它会随着时间的推移而减慢)
(旧视频,新代码不会将帧重置为0):

可在此处找到动画的图像资源:
https ://drive.google.com/open?id=0B3OoSBYuhlkgaGRtbERfbHVWb28