Question

我试图找出根据用户的时间和坐标来纠正我的星图视图的方法，但它并不准确，所以我想知道哪个部分是错误的。

我有两个节点，星图节点和摄像机节点，摄像机节点位于星图节点内，使其像360视图一样。这是我的方法：

1.注意加速度数据

motionManager.startAccelerometerUpdatesToQueue(NSOperationQueue.currentQueue()!, withHandler: {(accelerometerData, error) -> Void in

    self.outputAccelerationData(accelerometerData!.acceleration)

    if(error != nil) {
        print("\(error)")
    }
})

func outputAccelerationData(acceleration: CMAcceleration) {

    let accZ: Double = fabs(acceleration.z)
    rotateDegreeCameraX = acos(accZ) * 180 / M_PI

}

将相机节点更正为其正在查看的位置

//让摄影机节点从查看春分点开始//

  private func orientationFromCMQuaternion(attitudeQuaternion: CMQuaternion, trueHeading: Float) -> SCNVector4 { 
    let gq1 = GLKQuaternionMakeWithAngleAndAxis(GLKMathDegreesToRadians(Float(rotateDegreeCameraX) - 90), 1, 0, 0)
    let gq2 = GLKQuaternionMakeWithAngleAndAxis(GLKMathDegreesToRadians(180), 0, 0, 1)
    let gq3 = GLKQuaternionMakeWithAngleAndAxis(GLKMathDegreesToRadians(trueHeading), 0, 0, 1)       
    let gq4 = GLKQuaternionMake(Float(attitudeQuaternion.x), Float(attitudeQuaternion.y), Float(attitudeQuaternion.z), Float(attitudeQuaternion.w))

    let qp = GLKQuaternionMultiply(gq1, gq2)
    let qp2 = GLKQuaternionMultiply(qp, gq3)
    let qp3 = GLKQuaternionMultiply(qp2, gq4)
    let rq = CMQuaternion(x: Double(qp3.x), y: Double(qp3.y), z: Double(qp3.z), w: Double(qp3.w))
    return SCNVector4Make(Float(rq.x), Float(rq.y), Float(rq.z), Float(rq.w))
}

根据用户的时间和坐标

更正星图（SCNshpere）

func correctOfSkyMap（革命：浮动，旋转：浮动，纬度：浮动） - ＆gt; SCNVector4 {

 // rotate the sphere, making Equatorial plane is now same position with Ecliptic plane. (degrees: 23.4397) //
 let gq = GLKQuaternionMakeWithAngleAndAxis(GLKMathDegreesToRadians(-23.4397), 0, 0, 1)

 // rotate the sphere according to the gap between current date and the date vernal equinox pass 0 longitude //
 let gq2 = GLKQuaternionMakeWithAngleAndAxis(GLKMathDegreesToRadians(-revolution), 0, 1, 0)
 let qp = GLKQuaternionMultiply(gq, gq2)

 // rotate sphere back to where Equatorial plane is //
 let gq3 = GLKQuaternionMakeWithAngleAndAxis(GLKMathDegreesToRadians(-23.4397), 0, 0, 1)
 let qp2 = GLKQuaternionMultiply(qp, gq3)

 // rotate the sphere according to current time //
 let gq4 = GLKQuaternionMakeWithAngleAndAxis(GLKMathDegreesToRadians(-rotation), 0, 1, 0)
 let qp3 = GLKQuaternionMultiply(qp2, gq4)

 // rotate sphere according to user's latitude (adjust the degree of polaris) //
 let gq5 = GLKQuaternionMakeWithAngleAndAxis(GLKMathDegreesToRadians(latitude - 90), 1, 0, 0)
 let qp4 = GLKQuaternionMultiply(qp3, gq5)

 // after comparing with other star gazing app, finding the map needs to rotate 90 degrees to make it more accurate. //
 let gq6 = GLKQuaternionMakeWithAngleAndAxis(GLKMathDegreesToRadians(90), 0, 0, 1)
 let qp5 = GLKQuaternionMultiply(qp4, gq6)

 return SCNVector4Make(qp5.x, qp5.y, qp5.z, qp5.w)   }

以下是计算旋转和旋转的方法：

func calculateRevolution（） - ＆gt;浮动{

let degreePerDay: Double = 0.9656112744
let originalDate = NSDate()
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm"
dateFormatter.timeZone = NSTimeZone(abbreviation: "UTC")
let currentDateStr = dateFormatter.stringFromDate(originalDate)
if let currentDate = dateFormatter.dateFromString(currentDateStr),
    let vernalEquinox = dateFormatter.dateFromString("2016-03-20 04:30") {

    let currentDateInSecs = currentDate.timeIntervalSinceDate(vernalEquinox)
    let currentDateInDays = currentDateInSecs / (60 * 60 * 24)
    let rotateDegreesDouble = currentDateInDays * degreePerDay
    let rotateDegrees = Float(rotateDegreesDouble)

    return rotateDegrees

} else { return 0.0 }}

func calculateEarthRotation（） - ＆gt;浮动{

let degreePerMinute: Double = 0.25
let originalDate = NSDate()
let dateFormatter = NSDateFormatter()
dateFormatter.timeZone = NSTimeZone(abbreviation: "UTC")
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm"
let originalDateStr = dateFormatter.stringFromDate(originalDate)
if let currentDate = dateFormatter.dateFromString(originalDateStr) {
    let calendar = NSCalendar.currentCalendar()
    let hours = Double(calendar.component(.Hour, fromDate: currentDate))
    let minutes = Double(calendar.component(.Minute, fromDate: currentDate))

    print("pass time: \(hours * 60 + minutes)")
    print("Local date: \(originalDate)")
    print("Date in UTC: \(currentDate)")

    return Float((hours * 60 + minutes) * degreePerMinute)

} else {return 0.0}}

有人能给我一些准确的建议吗？提前谢谢。

Answer 1

缩小您的错误。有太多东西可能是错误的，任何人都无法检查。

RA /赤纬是否正确？你怎么知道的？

对于给定的RA / decl，您的恒星是否出现在外球体上的正确点上？你怎么知道的？

查看https://stackoverflow.com/help/mcve并发布我们可以运行的Playground兼容代码段并重现您的错误。

评论的截图也有帮助。

根据坐标和时间快速更改星图视图

1 个答案: