Enumeration: CMAttitudeReferenceFrame

Overview

Enum constants for indicating the reference frames from which all attitude samples are referenced.

CMAttitudeReferenceFrameXArbitraryZVertical Describes a reference frame in which the z axis is vertical and the x axis points in an arbitrary direction in the horizontal plane.available in ios 5.0 and later.declared in cmattitude.h.
CMAttitudeReferenceFrameXArbitraryCorrectedZVertical Describes the same reference frame as cmattitudereferenceframexarbitraryzvertical except that the magnetometer, when available and calibrated, is used to improve long-term yaw accuracy. using this constant instead of cmattitudereferenceframexarbitraryzvertical results in increased cpu usage.available in ios 5.0 and later.declared in cmattitude.h.
CMAttitudeReferenceFrameXMagneticNorthZVertical Describes a reference frame in which the z axis is vertical and the x axis points toward magnetic north. note that using this reference frame may require device movement to calibrate the magnetometer.available in ios 5.0 and later.declared in cmattitude.h.
CMAttitudeReferenceFrameXTrueNorthZVertical Describes a reference frame in which the z axis is vertical and the x axis points toward true north. note that using this reference frame may require device movement to calibrate the magnetometer. it also requires the location to be available in order to calculate the difference between magnetic and true north.available in ios 5.0 and later.declared in cmattitude.h.