VEX Distance Sensor C++ API

pros::Distance

Constructor(s)

Prototype
Example
pros::Distance(const std::uint8_t port)

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#define DISTANCE_PORT 1

void initialize() {
  pros::Distance distance_sensor(DISTANCE_PORT);
}
Parameters  
port The V5 port number from 1-21

Functions

get

Get the currently measured distance from the sensor in mm

This function uses the following values of errno when an error state is reached:

  • ENXIO - The given value is not within the range of V5 ports (1-21).
  • ENODEV - The port cannot be configured as an Distance Sensor.
Prototype
Example
std::int32_t get ( )

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#define DISTANCE_PORT 1

void opcontrol() {
  pros::Distance distance_sensor(DISTANCE_PORT);
  while (true) {
                printf("Distance: %d mm\n", distance_sensor.get());
                pros::delay(20);
  }
}
Parameters  
port The V5 port number from (1-21)

Returns: 1 if the operation was successful or PROS_ERR if the operation failed, setting errno.

get_confidence

Get the confidence in the distance reading

This is a value that has a range of 0 to 63. 63 means high confidence, lower values imply less confidence. Confidence is only available when distance is > 200mm (the value 10 is returned in this scenario).

This function uses the following values of errno when an error state is reached:

  • ENXIO - The given value is not within the range of V5 ports (1-21).
  • ENODEV - The port cannot be configured as an Distance Sensor.
Prototype
Example
std::int32_t get_confidence ( )

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#define DISTANCE_PORT 1

void opcontrol() {
  pros::Distance distance_sensor(DISTANCE_PORT);
  while (true) {
        printf("Distance Confidence Value: %d\n", distance_sensor.get_confidence(DISTANCE_PORT));
                pros::delay(20);
  }
}
Parameters  
port The V5 port number from (1-21)

Returns: 1 if the operation was successful or PROS_ERR if the operation failed, setting errno.

get_object_size

Get the current guess at relative object size

This is a value that has a range of 0 to 400. A 18” x 30” grey card will return a value of approximately 75 in typical room lighting.

This function uses the following values of errno when an error state is reached:

  • ENXIO - The given value is not within the range of V5 ports (1-21).
  • ENODEV - The port cannot be configured as an Distance Sensor.
Prototype
Example
std::int32_t get_object_size ( )

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#define DISTANCE_PORT 1

void opcontrol() {
  pros::Distance distance_sensor(DISTANCE_PORT);
  while (true) {
        printf("Distance Object Size: %d\n", distance_sensor.get_object_size(DISTANCE_PORT));
                pros::delay(20);
  }
}
Parameters  
port The V5 port number from (1-21)

Returns: 1 if the operation was successful or PROS_ERR if the operation failed, setting errno.

get_object_velocity

Get the object velocity in m/s

This function uses the following values of errno when an error state is reached:

  • ENXIO - The given value is not within the range of V5 ports (1-21).
  • ENODEV - The port cannot be configured as an Distance Sensor.
Prototype
Example
std::int32_t get_object_velocity ( )

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#define DISTANCE_PORT 1

void opcontrol() {
  pros::Distance distance_sensor(DISTANCE_PORT);
  while (true) {
        printf("Distance Object Velocity: %d\n", distance_sensor.get_object_velocity(DISTANCE_PORT));
                pros::delay(20);
  }
}
Parameters  
port The V5 port number from (1-21)

Returns: 1 if the operation was successful or PROS_ERR if the operation failed, setting errno.