# SoTimerQueueSensor Class Reference
[Sensor classes]

`#include <Inventor/sensors/SoTimerQueueSensor.h>`

Inheritance diagram for SoTimerQueueSensor:

List of all members.

## Detailed Description

The SoTimerQueueSensor class is the abstract base class for sensors triggering on certain timer events.

Timer sensors triggers upon specific points in time.

This class is an abstract superclass which collects the common interface of the various non-abstract timer sensor classes. See the documentation of the subclasses for information on what ways there are to specify base times, intervals, alarm-style single triggering, repeated triggers, etc.

Note that Coin timer sensors should in no way be considered "hard real-time". That is, you can not expect a timer to always trigger at the exact moment it was set up for. Delays in triggering could be due to other activities in Coin, a task suspended, or heavy load from other applications on the system. These situations could all cause the processing of sensor queues (from SoQt / SoWin / SoXt / whatever) to be slightly delayed, thereby causing delays in timer sensor triggering.

On modern systems, a timer will usually trigger within a few milliseconds of it's designated time, though.

If a timer sensor can not trigger at the exact moment it has been scheduled, it will be triggered at the first opportunity after the scheduled time has passed.

Here's a simple usage example. It's a stand-alone example, which only demonstrates how to set up a repeating timer sensor with a callback:

      #include <Inventor/Xt/SoXt.h>
      #include <Inventor/sensors/SoTimerSensor.h>
      #include <stdio.h>

      static void
      timeSensorCallback(void * data, SoSensor * sensor)
      {
        SbTime time = SbTime::getTimeOfDay();
        SbString string = time.format("%S.%i");
        (void)printf("%s\n", string.getString());
      }

      int
      main(int argc, char ** argv)
      {
        SoXt::init("test");

        SoTimerSensor * timeSensor = new SoTimerSensor;
        timeSensor->setFunction(timeSensorCallback);
        timeSensor->setBaseTime(SbTime::getTimeOfDay());
        timeSensor->setInterval(1.0f);
        timeSensor->schedule();

        SoXt::mainLoop();
        return 0;
      }

## Public Member Functions

| SoTimerQueueSensor (void)
| SoTimerQueueSensor (SoSensorCB *func, void *data)
virtual | ~SoTimerQueueSensor (void)
const SbTime & | getTriggerTime (void) const
virtual void | schedule (void)
virtual void | unschedule (void)
virtual SbBool | isScheduled (void) const
virtual void | trigger (void)

## Protected Member Functions

void | setTriggerTime (const SbTime &time)

## Protected Attributes

SbBool | scheduled

## Constructor & Destructor Documentation

SoTimerQueueSensor::SoTimerQueueSensor | ( | void |  | ) |

| Default constructor.

SoTimerQueueSensor::SoTimerQueueSensor | ( | SoSensorCB * | func,
|  | void * | data
| ) |

Constructor taking as arguments the sensor callback function and the userdata which will be passed the callback.

See also:
  setFunction(), setData()

SoTimerQueueSensor::~SoTimerQueueSensor | ( | void |  | ) | `[virtual]`

| Destructor.

## Member Function Documentation

const SbTime & SoTimerQueueSensor::getTriggerTime | ( | void |  | ) | const

Returns the time at which the sensor will trigger.

See also:
  setTriggerTime()

void SoTimerQueueSensor::schedule | ( | void |  | ) | `[virtual]`

Put the sensor in the global timer queue.

See also:
  unschedule(), isScheduled()

Implements SoSensor.

Reimplemented in SoAlarmSensor, and SoTimerSensor.

void SoTimerQueueSensor::unschedule | ( | void |  | ) | `[virtual]`

Remove sensor from the timer queue, without triggering it first.

See also:
  schedule(), isScheduled()

Implements SoSensor.

Reimplemented in SoTimerSensor.

SbBool SoTimerQueueSensor::isScheduled | ( | void |  | ) | const`[virtual]`

Check if this sensor is scheduled for triggering.

See also:
  schedule(), unschedule()

Implements SoSensor.

void SoTimerQueueSensor::trigger | ( | void |  | ) | `[virtual]`

| Trigger the sensor's callback function. Reimplemented from SoSensor.

void SoTimerQueueSensor::setTriggerTime | ( | const SbTime & | time | ) | `[protected]`

Set absolute time at which to trigger sensor.

See also:
  getTriggerTime()

## Member Data Documentation

SbBool SoTimerQueueSensor::scheduled`[protected]`

| `TRUE` if the sensor is currently scheduled.

The documentation for this class was generated from the following files:

- SoTimerQueueSensor.h
- SoTimerQueueSensor.cpp