class PGCameraDeviceAngleSampler
@property (nonatomic, copy) void(^deviceOrientationChanged)(UIDeviceOrientation orientation);
@property (nonatomic, readonly) UIDeviceOrientation deviceOrientation;
@property (nonatomic, readonly) bool isMeasuring;
@property (nonatomic, readonly) CGFloat currentDeviceAngle;
- (void)startMeasuring;
- (void)stopMeasuring;
// init
// 关注：CMMotionManager
- (instancetype)init
{
self = [super init];
if (self != nil)
{
_deviceOrientation = UIDeviceOrientationUnknown;
_motionManager = [[CMMotionManager alloc] init];
_motionManager.accelerometerUpdateInterval = 1.0f;
_motionManager.deviceMotionUpdateInterval = 1.0f;
_motionManager.gyroUpdateInterval = 1.0f;
_motionManager.magnetometerUpdateInterval = 1.0f;
_motionQueue = [[NSOperationQueue alloc] init];
}
return self;
}
- (void)dealloc
{
[self stopMeasuring];
}
- (bool)isMeasuring
{
return [_motionManager isDeviceMotionActive];
}
- (void)stopMeasuring
{
[_motionManager stopDeviceMotionUpdates];
}
- (void)startMeasuring
{
if (![_motionManager isDeviceMotionAvailable])
return;
__weak PGCameraDeviceAngleSampler *weakSelf = self;
[_motionManager startAccelerometerUpdatesToQueue:_motionQueue withHandler:^(CMAccelerometerData *accelerometerData, __unused NSError *error)
{
__strong PGCameraDeviceAngleSampler *strongSelf = weakSelf;
if (strongSelf == nil || accelerometerData == nil || error != nil)
return;
CMAcceleration acceleration = accelerometerData.acceleration;
CGFloat xx = -acceleration.x;
CGFloat yy = acceleration.y;
CGFloat z = acceleration.z;
CGFloat angle = atan2(yy, xx);
UIDeviceOrientation deviceOrientation = strongSelf.deviceOrientation;
CGFloat absoluteZ = fabs(z);
if (deviceOrientation == UIDeviceOrientationFaceUp || deviceOrientation == UIDeviceOrientationFaceDown)
{
if (absoluteZ < 0.845f)
{
if (angle < -2.6f)
deviceOrientation = UIDeviceOrientationLandscapeRight;
else if (angle > -2.05f && angle < -1.1f)
deviceOrientation = UIDeviceOrientationPortrait;
else if (angle > -0.48f && angle < 0.48f)
deviceOrientation = UIDeviceOrientationLandscapeLeft;
else if (angle > 1.08f && angle < 2.08f)
deviceOrientation = UIDeviceOrientationPortraitUpsideDown;
}
else if (z < 0.f)
{
deviceOrientation = UIDeviceOrientationFaceUp;
}
else if (z > 0.f)
{
deviceOrientation = UIDeviceOrientationFaceDown;
}
}
else
{
if (z > 0.875f)
{
deviceOrientation = UIDeviceOrientationFaceDown;
}
else if (z < -0.875f)
{
deviceOrientation = UIDeviceOrientationFaceUp;
}
else
{
switch (deviceOrientation)
{
case UIDeviceOrientationLandscapeLeft:
if (angle < -1.07f) deviceOrientation = UIDeviceOrientationPortrait;
if (angle > 1.08f) deviceOrientation = UIDeviceOrientationPortraitUpsideDown;
break;
case UIDeviceOrientationLandscapeRight:
if (angle < 0.f && angle > -2.05f) deviceOrientation = UIDeviceOrientationPortrait;
if (angle > 0.f && angle < 2.05f) deviceOrientation = UIDeviceOrientationPortraitUpsideDown;
break;
case UIDeviceOrientationPortraitUpsideDown:
if (angle > 2.66f) deviceOrientation = UIDeviceOrientationLandscapeRight;
if (angle < 0.48f) deviceOrientation = UIDeviceOrientationLandscapeLeft;
break;
case UIDeviceOrientationPortrait:
default:
if (angle > -0.47f) deviceOrientation = UIDeviceOrientationLandscapeLeft;
if (angle < -2.64f) deviceOrientation = UIDeviceOrientationLandscapeRight;
break;
}
}
}
if (deviceOrientation != strongSelf.deviceOrientation)
{
strongSelf->_deviceOrientation = deviceOrientation;
TGDispatchOnMainThread(^
{
if (strongSelf.deviceOrientationChanged != nil)
strongSelf.deviceOrientationChanged(deviceOrientation);
});
}
}];
[_motionManager startDeviceMotionUpdatesUsingReferenceFrame:CMAttitudeReferenceFrameXArbitraryZVertical toQueue:_motionQueue withHandler:^(CMDeviceMotion *motion, __unused NSError *error)
{
__strong PGCameraDeviceAngleSampler *strongSelf = weakSelf;
if (strongSelf == nil)
return;
strongSelf->_currentDeviceAngle = TGRadiansToDegrees((CGFloat)(atan2(motion.gravity.x, motion.gravity.y) - M_PI)) * -1;
}];
}