IOS 之螺旋仪与加速计, 磁力计

妖狐艹你老母 2022-09-18 03:54 129阅读 0赞

IOS最重要的特性之一是加速计与螺旋仪,是由CMMotionManager负责管理,在这个类里有3个特性,分别是加速计,螺旋仪,磁力计.

1.加速计

motionManager = [[CMMotionManager alloc] init];
        NSOperationQueue* queue = [[NSOperationQueue alloc] init];
        if ( _motionManager.accelerometerAvailable ) {
            _motionManager.accelerometerUpdateInterval = UPDATEINTERVAL;
            [_motionManager startAccelerometerUpdatesToQueue:queue withHandler:^(CMAccelerometerData *accelerometerData, NSError *error) {
                if ( error ) {
                    [_motionManager stopAccelerometerUpdates];
                    NSLog(@"加速计发生错误!");
                    return ;
                }
                CMAcceleration accleration = accelerometerData.acceleration;
                NSString* temp = [NSString stringWithFormat:@"x: %+.2f\ny: %+.2f\nz: %+.2f",
                                  accleration.x,
                                  accleration.y,
                                  accleration.z];
                [self.accelerometer performSelectorOnMainThread:@selector(setText:) withObject:temp waitUntilDone:NO];
            }];
        }else{
            NSLog(@"设备不支持加速计!");
        }

![acceleration_axes_2x.png][]个人理解,加速主要用x,y,z三轴来判断手机的摆放位置,还有测重力感应.

2.螺旋仪

CMMotionManager _motionManager = [[CMMotionManager alloc] init];
    NSOperationQueue* queue = [[NSOperationQueue alloc] init];
    if ( _motionManager.gyroAvailable ) {
            _motionManager.gyroUpdateInterval = UPDATEINTERVAL;
            [_motionManager startGyroUpdatesToQueue:queue withHandler:^(CMGyroData *gyroData, NSError *error) {
                if ( error ) {
                    [_motionManager stopGyroUpdates];
                    NSLog(@"螺旋仪发生错误!");
                    return ;
                }
                NSString* temp = [NSString stringWithFormat:@"x: %+.2f\ny: %+.2f\nz: %+.2f",
                                  gyroData.rotationRate.x,
                                  gyroData.rotationRate.y,
                                  gyroData.rotationRate.z];
                [self.gyro performSelectorOnMainThread:@selector(setText:) withObject:temp waitUntilDone:NO];
                
            }];
        }else{
            NSLog(@"设备不支持螺旋仪!");
        }

![gyro_rotation_2x.png][]个人理解,螺旋仪主1要用x,y,z三軸来判断移动的速率,也可以测量重力感情.. 跟加速计的区别在于,在静止时,螺旋仪的每个轴都为0, 但是加速计则根据手机的摆放位置,xyz的每个轴的数也会不一样!

3.磁力计

CMMotionManager _motionManager = [[CMMotionManager alloc] init];
        NSOperationQueue* queue = [[NSOperationQueue alloc] init];
    if ( _motionManager.magnetometerAvailable ) {
            _motionManager.magnetometerUpdateInterval = UPDATEINTERVAL;
            [_motionManager startMagnetometerUpdatesToQueue:queue withHandler:^(CMMagnetometerData *magnetometerData, NSError *error) {
                if ( error ) {
                    [_motionManager stopMagnetometerUpdates];
                    NSLog(@"磁力计发生错误!");
                    return ;
                }
                NSString* temp = [NSString stringWithFormat:@"x: %+.2f\ny: %+.2f\nz: %+.2f",
                                  magnetometerData.magneticField.x,
                                  magnetometerData.magneticField.y,
                                  magnetometerData.magneticField.z];
                [self.magne performSelectorOnMainThread:@selector(setText:) withObject:temp waitUntilDone:NO];
            }];
        }else{
            NSLog(@"设备不支持磁力计!");
        }

没怎么用过.好像是测东南西北的吧

[acceleration_axes_2x.png]: /images/20220828/833e7e2b1dee4260a6bf0b1f4a09d4e3.png
[gyro_rotation_2x.png]: /images/20220828/a4efd4247f74488eacb5f69752854dd5.png