Ios 使用动画旋转图像,然后读取旋转
我正在实现一个带有CAKeyframeAnimation的命运之轮,并尝试在动画停止后读取结果。但在这里我没有得到确定性的结果。 动画停止后是否无法读取旋转 这里是我的动画代码:Ios 使用动画旋转图像,然后读取旋转,ios,swift,animation,cakeyframeanimation,Ios,Swift,Animation,Cakeyframeanimation,我正在实现一个带有CAKeyframeAnimation的命运之轮,并尝试在动画停止后读取结果。但在这里我没有得到确定性的结果。 动画停止后是否无法读取旋转 这里是我的动画代码: let anim = CAKeyframeAnimation(keyPath: "transform.rotation.z") anim.duration = max(strength / 2, 1.0) anim.isCumulative = true anim.val
let anim = CAKeyframeAnimation(keyPath: "transform.rotation.z")
anim.duration = max(strength / 2, 1.0)
anim.isCumulative = true
anim.values = [NSNumber(value: Float(p)), Float(circleRotationOffset)]
anim.keyTimes = [NSNumber(value: Float(0)),NSNumber(value: Float(1.0))]
anim.timingFunctions = [CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseOut)]
anim.isRemovedOnCompletion = false
anim.fillMode = kCAFillModeForwards
anim.delegate = self
wheelImage.layer.removeAllAnimations()
wheelImage.layer.add(anim, forKey: "rotate")
这是我如何解读旋转的:
func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
readImageOrientation()
}
func readImageOrientation(){
let radians:Double = atan2( Double(wheelImage.transform.b), Double(wheelImage.transform.a))
let degrees:CGFloat = CGFloat(radians) * (CGFloat(180) / CGFloat(M_PI))
sectionForDegrees(degree: degrees)
}
let view = UIImageView()
view.transform = CGAffineTransform(rotationAngle: 0.02);
let x = view.value(forKeyPath: "layer.transform.rotation.z")
let a = acos(view.transform.a)
let b = asin(view.transform.b)
let c = atan2(view.transform.b, view.transform.a)
print(a)
print(b)
print(c)
print(x!)
为了完整起见,这里是我的全班
class WOFView: UIView, CAAnimationDelegate {
@IBOutlet weak var wheelImage: UIImageView!
private var history = [Dictionary<String, Any>]()
private var rotation: CGFloat = 0
private var startAngle: CGFloat = 0
private var circleRotationOffset: CGFloat = 0
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesBegan(touches, with: event)
if let touchPoint = touches.first?.location(in: self){
if startAngle == 0{
startAngle = atan2(self.frame.width - touchPoint.y, self.frame.height - touchPoint.x)
}
rotation = startAngle
if !touch(touches.first!, isInLeftHalfOf: wheelImage) {
rotation = -rotation
}
history.removeAll()
}
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesMoved(touches, with: event)
guard let touchPoint = touches.first?.location(in: self) else {
return
}
let dic = ["time" : NSNumber(value: CFAbsoluteTimeGetCurrent()),
"point": NSValue(cgPoint: touchPoint),
"rotation": NSNumber(value: Float(circleRotationOffset + rotation))]
history.insert(dic, at: 0)
if history.count == 3{
history.removeLast()
}
rotation = atan2(self.frame.width - touchPoint.y, self.frame.height - touchPoint.x) - startAngle
if !touch(touches.first!, isInLeftHalfOf: wheelImage) {
rotation = -rotation
}
wheelImage.transform = CGAffineTransform(rotationAngle: circleRotationOffset + rotation)
print("offset: \(circleRotationOffset)")
readImageOrientation()
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesEnded(touches, with: event)
guard let touchPoint = touches.first?.location(in: self) else {
return
}
guard let lastObject = history.last else{
return
}
guard let pointValue = lastObject["point"] as? CGPoint else{
return
}
guard let timeValue = lastObject["time"] as? NSNumber else {
return
}
guard let rotationValue = lastObject["rotation"] as? NSNumber else {
return
}
let timeDif = CFAbsoluteTimeGetCurrent() - (timeValue.doubleValue)
circleRotationOffset = circleRotationOffset + rotation
let lastRotation = rotationValue.floatValue
let dist = sqrt(((pointValue.x - touchPoint.x) * (pointValue.x - touchPoint.x)) +
((pointValue.y - touchPoint.y) * (pointValue.y - touchPoint.y)))
let strength = max(Double(min(1.0, dist / 80.0)) * (timeDif / 0.25) * M_PI * 2, 0.3) * 30
let p = circleRotationOffset
let dif = circleRotationOffset - CGFloat(lastRotation)
var inc = dif > 0
if dif > 3 || dif < -3{
inc = !inc
}
if (inc){
circleRotationOffset += CGFloat(strength)
}else{
circleRotationOffset -= CGFloat(strength)
}
let anim = CAKeyframeAnimation(keyPath: "transform.rotation.z")
anim.duration = max(strength / 2, 1.0)
anim.isCumulative = true
anim.values = [NSNumber(value: Float(p)), Float(circleRotationOffset)]
anim.keyTimes = [NSNumber(value: Float(0)),NSNumber(value: Float(1.0))]
anim.timingFunctions = [CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseOut)]
anim.isRemovedOnCompletion = false
anim.fillMode = kCAFillModeForwards
anim.delegate = self
wheelImage.layer.removeAllAnimations()
wheelImage.layer.add(anim, forKey: "rotate")
}
func touch(_ touch:UITouch, isInLeftHalfOf view: UIView) -> Bool {
let positionInView = touch.location(in: view)
return positionInView.x < view.frame.midX
}
func touch(_ touch:UITouch, isInUpperHalfOf view: UIView) -> Bool {
let positionInView = touch.location(in: view)
return positionInView.y < view.frame.midY
}
func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
readImageOrientation()
}
func readImageOrientation(){
let radians:Double = acos(Double(wheelImage.transform.a))
let degrees:CGFloat = CGFloat(radians) * (CGFloat(180) / CGFloat(M_PI))
sectionForDegrees(degree: degrees)
}
func sectionForDegrees(degree: CGFloat){
var result = "not defined"
switch degree{
case 0 ... 90:
result = "3 \(degree)"
case 90.1...180:
result = "2 \(degree)"
case 181.1...270:
result = "1 \(degree)"
case 270.1...360:
result = "4 \(degree)"
default:
result = "not defined: \(degree)"
}
print(result)
}
类WOFView:UIView,CAAnimationDelegate{
@ibimage:UIImageView!
私有变量历史=[Dictionary]()
私有变量旋转:CGFloat=0
私有变量startAngle:CGFloat=0
专用变量CirclerRotationOffset:CGFloat=0
覆盖func TouchesBegind(Touchs:Set,带有事件:UIEvent?){
super.touchesbeated(touches,with:event)
如果让接触点=接触.first?位置(in:self){
如果startAngle==0{
startAngle=atan2(self.frame.width-touchPoint.y,self.frame.height-touchPoint.x)
}
旋转=星缠结
if!touch(touch.first!),isInLeftHalfOf:wheelImage){
旋转=-旋转
}
history.removeAll()
}
}
覆盖功能触摸移动(touchs:Set,带有事件:UIEvent?){
super.touchesMoved(touches,with:event)
guard let touchPoint=触碰.first?位置(in:self)else{
返回
}
让dic=[“时间”:NSNumber(值:CFAbsoluteTimeGetCurrent()),
“点”:NSValue(cgPoint:接触点),
“旋转”:NSNumber(值:浮点(圆圈旋转偏移+旋转))]
历史。插入(dic,地址:0)
如果history.count==3{
history.removeLast()
}
旋转=atan2(self.frame.width-touchPoint.y,self.frame.height-touchPoint.x)-startAngle
if!touch(touch.first!),isInLeftHalfOf:wheelImage){
旋转=-旋转
}
wheelImage.transform=CGAffineTransform(旋转角度:圆形旋转偏移+旋转)
打印(“偏移量:\(圆圈旋转偏移量)”)
readImageOrientation()
}
覆盖函数touchesend(touchs:Set,带有事件:UIEvent?){
super.touchesend(触摸,带有:事件)
guard let touchPoint=触碰.first?位置(in:self)else{
返回
}
guard let lastObject=history.last else{
返回
}
guard let pointValue=lastObject[“point”]作为?CGPoint else{
返回
}
guard let timeValue=lastObject[“time”]作为?NSNumber else{
返回
}
guard let rotationValue=lastObject[“rotation”]作为?NSNumber else{
返回
}
让timeDif=CFAbsoluteTimeGetCurrent()-(timeValue.doubleValue)
CirclerRotationOffset=CirclerRotationOffset+旋转
设lastRotation=rotationValue.floatValue
设dist=sqrt(((pointValue.x-touchPoint.x)*(pointValue.x-touchPoint.x))+
((pointValue.y-touchPoint.y)*(pointValue.y-touchPoint.y)))
让强度=最大值(双倍(最小值(1.0,dist/80.0))*(时间差/0.25)*M_PI*2,0.3)*30
设p=圆旋转偏移量
设dif=CirclerRotationOffset-CGFloat(上次旋转)
var inc=dif>0
如果dif>3 | | dif<-3{
公司
}
if(公司){
CirclerRotationOffset+=CGFloat(强度)
}否则{
圆环旋转偏移量-=CGFloat(强度)
}
让anim=CAKeyframeAnimation(关键路径:“transform.rotation.z”)
动画持续时间=最大(强度/2,1.0)
anim.isCumulative=真
anim.values=[NSNumber(值:Float(p)),Float(circleRotationOffset)]
anim.keyTimes=[NSNumber(值:Float(0)),NSNumber(值:Float(1.0))]
anim.timingFunctions=[CAMediaTimingFunction(名称:kCAMediaTimingFunctionEaseOut)]
anim.isRemovedOnCompletion=false
anim.fillMode=kCAFillModeForwards
anim.delegate=self
wheelImage.layer.RemoveAllianimations()文件
wheelImage.layer.add(动画,福克斯:“旋转”)
}
func touch(utouch:UITouch,isInLeftHalfOf view:UIView)->Bool{
让位置查看=触摸位置(在:视图中)
返回位置inview.xBool{
让位置查看=触摸位置(在:视图中)
返回位置查看y
}
原始答案(关于转换的一般想法)
根据三维旋转矩阵的外观,我认为应该使用acos()
而不是atan2()
:
在这个Rz矩阵中,我们可以看到变换.a和变换.b将作为余弦θ给出。参考:
在没有测试的情况下,我非常确定一个简单的acos(Double(wheelmeage.transform.a))
就足以让您实现θ旋转。编辑:这是错误的建议,用acos
替换atan2
意味着你必须检查你的答案是正余弦值还是负余弦值,这完全没有意义。要记住的另一件事是,如果对控制盘应用任何缩放,变换也会发生变化
如果我错了,您可以始终使用强度值来计算车轮旋转的时间,并从中找到角度。这将需要您了解kCamediatimingFunctionaleaseout
是如何准确工作的,因此我建议您将动画更改为
let view = UIImageView()
view.transform = CGAffineTransform(rotationAngle: 0.02);
let x = view.value(forKeyPath: "layer.transform.rotation.z")
let a = acos(view.transform.a)
let b = asin(view.transform.b)
let c = atan2(view.transform.b, view.transform.a)
print(a)
print(b)
print(c)
print(x!)
0.0200000000000011
0.02
0.02
0.02