[WorldWind学习]5.相机对象

　　首先查看WorldWindow的事件：OnMouseUp、OnMouseMove、HandleKeyDown，这几个方法中多次调用this.drawArgs.WorldCamera的各种属性实现了场景的控制，包括球的旋转、场景的放大缩小，上下移动。

　　1. 接下来查看CameraBase类RotationYawPitchRoll虚函数：

public virtual void RotationYawPitchRoll(Angle yaw, Angle pitch, Angle roll)
        {
        //    this._orientation *= MathEngine.EulerToQuaternion(yaw.Radians, pitch.Radians, roll.Radians);
        //    Vector3 v = MathEngine.QuaternionToEuler(this._orientation);
            
        //    if(!double.IsNaN(v.Y))
        //        this._latitude.Radians = v.Y;
        //    if(!double.IsNaN(v.X))
        //        this._longitude.Radians = v.X;
        //    if(Math.Abs(roll.Radians)>Single.Epsilon)
        //        this._heading.Radians = v.Z;


            m_Orientation = Quaternion4d.EulerToQuaternion(yaw.Radians, pitch.Radians, roll.Radians) * m_Orientation;

            Point3d p = Quaternion4d.QuaternionToEuler(m_Orientation);
            if(!double.IsNaN(p.Y))
                _latitude.Radians = p.Y;
            if(!double.IsNaN(p.X))
                _longitude.Radians = p.X;
            if(Math.Abs(roll.Radians) > double.Epsilon)
                _heading.Radians = p.Z;
        }

　　WorldCamera类的RotationYawPitchRoll方法：

public override void RotationYawPitchRoll(Angle yaw, Angle pitch, Angle roll)
        {
            _targetOrientation = Quaternion4d.EulerToQuaternion(yaw.Radians, pitch.Radians, roll.Radians) * _targetOrientation;
            
            Point3d v = Quaternion4d.QuaternionToEuler(_targetOrientation);
            if(!double.IsNaN(v.Y))
                this._targetLatitude.Radians = v.Y;
            if(!double.IsNaN(v.X))
                this._targetLongitude.Radians = v.X;
            if(Math.Abs(roll.Radians)>double.Epsilon)
                this._targetHeading.Radians = v.Z;
        }

　　MomentumCamera类的RotationYawPitchRoll方法：

public override void RotationYawPitchRoll(Angle yaw, Angle pitch, Angle roll)
        {
            if(World.Settings.cameraHasMomentum)
            {
                _latitudeMomentum += pitch/100;
                _longitudeMomentum += yaw/100;
                _headingMomentum += roll/100;
            }

            this._targetOrientation = Quaternion4d.EulerToQuaternion( yaw.Radians, pitch.Radians, roll.Radians ) * _targetOrientation;
            Point3d v = Quaternion4d.QuaternionToEuler(_targetOrientation);
            if(!double.IsNaN(v.Y))
            {
                this._targetLatitude.Radians = v.Y;
                this._targetLongitude.Radians = v.X;
                if(!World.Settings.cameraTwistLock)
                    _targetHeading.Radians = v.Z;
            }

            base.RotationYawPitchRoll(yaw,pitch,roll);
        }

　　2. CameraBase类的Pan方法：

/// <summary>
        /// Pan the camera using delta values
        /// 平移相机，采用经纬度偏移量
        /// </summary>
        /// <param name="lat">Latitude offset</param>
        /// <param name="lon">Longitude offset</param>
        public virtual void Pan(Angle lat, Angle lon)
        {
            if(Angle.IsNaN(lat)) lat = this._latitude;
            if(Angle.IsNaN(lon)) lon = this._longitude;
            lat += _latitude;
            lon += _longitude;

        //    this._orientation = MathEngine.EulerToQuaternion(
        //        lon.Radians,
        //        lat.Radians,
        //        _heading.Radians);

            m_Orientation = Quaternion4d.EulerToQuaternion(
                lon.Radians, lat.Radians, _heading.Radians);

            Point3d p = Quaternion4d.QuaternionToEuler(m_Orientation);

        //    Vector3 v = MathEngine.QuaternionToEuler(this._orientation);
        //    if(!double.IsNaN(v.Y))
        //    {
        //        this._latitude.Radians = v.Y;
        //        this._longitude.Radians = v.X;
        //    }

            if(!double.IsNaN(p.Y))
            {
                _latitude.Radians = p.Y;
                _longitude.Radians = p.X;
            }
        }

　　MomentumCamera类的Pan方法：

public override void Pan(Angle lat, Angle lon)
        {
            if(World.Settings.cameraHasMomentum)
            {
                _latitudeMomentum += lat/100;
                _longitudeMomentum += lon/100;
            }

            if(Angle.IsNaN(lat)) lat = this._targetLatitude;
            if(Angle.IsNaN(lon)) lon = this._targetLongitude;
            lat += _targetLatitude;
            lon += _targetLongitude;

            if(Math.Abs(lat.Radians)>Math.PI/2-1e-3)
            {
                lat.Radians = Math.Sign(lat.Radians)*(Math.PI/2 - 1e-3);
            }

            this._targetOrientation = Quaternion4d.EulerToQuaternion(
                lon.Radians,
                lat.Radians,
                _targetHeading.Radians);

            Point3d v = Quaternion4d.QuaternionToEuler(this._targetOrientation);
            if(!double.IsNaN(v.Y))
            {
                _targetLatitude.Radians = v.Y;
                _targetLongitude.Radians = v.X;
                _targetHeading.Radians = v.Z;

                if(!World.Settings.cameraSmooth)
                {
                    _latitude = _targetLatitude;
                    _longitude = _targetLongitude;
                    _heading = _targetHeading;
                    m_Orientation = _targetOrientation;
                }
            }
        }

错误 1 无法注册程序集“F:\World_Wind_1.4.0_Source\HtmlEditor\bin\Debug\HtmlEditor.dll”- 拒绝访问。请确保您正在以管理员身份运行应用程序。对注册表项“HKEY_CLASSES_ROOT\onlyconnect.HtmlDialog”的访问被拒绝。 HtmlEditor

解决方法：HtmlEditor项目的属性，取消“生成（Build ）”选项卡的为COM互操作注册