Class: Clock

Clock(clockTypeopt)

- Class representing a Clock in ROS

Constructor

new Clock(clockTypeopt)

Create a Clock.
Parameters:
Name Type Attributes Default Description
clockType ClockType <optional>
 Clock.ClockType.SYSTEM_TIME The type of the clock to be created.
Source:

Members

clockType

Get ClockType of this Clock object.
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Methods

addClockCallback(callbackObject, onClockChange, minForward, minBackward)

Add a clock callback.
Parameters:
Name Type Description
callbackObject object The object containing callback methods.
Properties
Name Type Attributes Description
_pre_callback function <optional>
 Optional callback invoked before a time jump. Takes no arguments.
_post_callback function <optional>
 Optional callback invoked after a time jump. Receives a jumpInfo object with properties: - clock_change {number}: Type of clock change that occurred. - delta {bigint}: Time delta in nanoseconds.
onClockChange boolean Whether to call the callback on clock change.
minForward bigint Minimum forward jump in nanoseconds to trigger the callback.
minBackward bigint Minimum backward jump in nanoseconds to trigger the callback.
Source:

now() → {Time}

Return the current time.
Source:
Returns:
Return the current time.
Type
Time

removeClockCallback(callbackObject)

Remove a clock callback.
Parameters:
Name Type Description
callbackObject object The callback object that was previously registered with addClockCallback().
Source:

(async) sleepFor(duration, contextopt) → {Promise.<boolean>}

Sleep for a specified duration. Equivalent to: clock.sleepUntil(clock.now() + duration, context) When using a ROSClock, this may sleep forever if the TimeSource is misconfigured and the context is never shut down. ROS time being activated or deactivated causes this function to cease sleeping and return false.
Parameters:
Name Type Attributes Default Description
duration Duration Duration of time to sleep for.
context Context <optional>
 null Context which when shut down will cause this sleep to wake early. If context is null, then the default context is used.
Source:
Throws:
if context has not been initialized or is shutdown.
Type
Error
Returns:
Promise that resolves to true if the full duration was slept, or false if it woke for another reason.
Type
Promise.<boolean>

(async) sleepUntil(until, contextopt) → {Promise.<boolean>}

Sleep until a specific time is reached on this Clock. When using a ROSClock, this may sleep forever if the TimeSource is misconfigured and the context is never shut down. ROS time being activated or deactivated causes this function to cease sleeping and return false.
Parameters:
Name Type Attributes Default Description
until Time Time at which this function should stop sleeping.
context Context <optional>
 null Context whose validity will be checked while sleeping. If context is null, then the default context is used. If the context is found to be shut down before or by the time the wait completes, the returned promise resolves to false.
Source:
Throws:
  • if until is specified for a different type of clock than this one.
    Type
    TypeError
  • if context has not been initialized or is shutdown.
    Type
    Error
Returns:
Promise that resolves to true if 'until' was reached without detecting a time jump or a shut down context, or false otherwise (for example, if a time jump occurred or the context is no longer valid when the wait completes).
Type
Promise.<boolean>