CMClock

init

static init(object: CMClock): CMClock

init(referencing object: CMClock)

anchorTime

anchorTime(): { "anchorTime": CMTime; "referenceTime": CMTime }

func anchorTime() throws -> (anchorTime: CMTime, referenceTime: CMTime)

Retrieves the current time from a clock and also the matching time from the clock's reference clock. To make practical use of this, you may need to know what the clock's reference clock is.

invalidate

invalidate(): void

func invalidate()

Makes the clock stop functioning. After invalidation, the clock will return errors from all APIs. This should only be called by the "owner" of the clock, who knows (for example) that some piece of hardware has gone away, and the clock will no longer work (and might even crash).

mightDrift

mightDrift(otherClock: CMClock): boolean

func mightDrift(relativeTo otherClock: CMClock) -> Bool

Indicates whether it is possible for the clock to drift relative to the `otherClock`.

hostTimeClock

static get hostTimeClock(): CMClock

static var hostTimeClock: CMClock { get }

The singleton clock logically identified with host time. On Mac OS X, the host time clock uses `mach_absolute_time` but returns a value with a large integer timescale (eg, nanoseconds).

convertHostTimeToSystemUnits

static convertHostTimeToSystemUnits(hostTime: CMTime): number

static func convertHostTimeToSystemUnits(_ hostTime: CMTime) -> UInt64

Converts a host time from `CMTime` to the host time's native units. This function performs a scale conversion, not a clock conversion. It can be more accurate than `CMTimeConvertScale` because the system units may have a non-integer timescale. On Mac OS X, this function converts to the units of `mach_absolute_time`.

convertSystemUnitsToHostTime

static convertSystemUnitsToHostTime(systemUnits: number): CMTime

static func convertSystemUnitsToHostTime(_ systemUnits: UInt64) -> CMTime

Converts a host time from native units to `CMTime`. The returned value will have a large integer timescale (eg, nanoseconds). This function handles situations where host time's native units use a non-integer timescale. On Mac OS X, this function converts from the units of `mach_absolute_time`.

nextPreferredStartTimePattern

nextPreferredStartTimePattern(): (CMClock_StartTimePattern) | null

func nextPreferredStartTimePattern() -> CMClock.StartTimePattern?

Returns the pattern of preferred start times, such as for synchronization with an external genlock signal. When a genlock signal is present and disciplined, this function returns a matched time pair in the near future and the delta between successive times.

implementsPreferredStartTimePattern

get implementsPreferredStartTimePattern(): boolean

var implementsPreferredStartTimePattern: Bool { get }

Indicates whether this clock implements preferred start time patterns.

time

get time(): CMTime

var time: CMTime { get }

The current time.

typeID

static get typeID(): number

static var typeID: CFTypeID { get }

The `CFTypeID` corresponding to `CMClock`.