Class Command::HighResAngleField

Nested Relationships

This class is a nested type of Class Command.

Class Documentation

class HighResAngleField

A message field for an angle measurement which does not lose precision at very high angles.

This field is represented as an int64_t for the number of revolutions and a float for the radian offset from that number of revolutions.

Public Functions

HighResAngleField(HebiCommandRef &internal, HebiCommandHighResAngleField field)
inline explicit operator bool() const

Allows casting to a bool to check if the field has a value without directly calling has().

This can be used as in the following (assuming ‘parent’ is a parent message, and this field is called ‘myField’) 

Command::HighResAngleField& f = parent.myField();
if (f)
  std::cout << "Field has value: " << f.get() << std::endl;
else
  std::cout << "Field has no value!" << std::endl;

bool has() const

True if (and only if) the field has a value.

double get() const

If the field has a value, returns that value as a double; otherwise, returns a default.

Note that some precision might be lost converting to a double at very high number of revolutions.

void get(int64_t *revolutions, float *radian_offset) const

If the field has a value, returns that value in the int64 and float parameters passed in; otherwise, returns a default.

Note that this maintains the full precision of the underlying angle measurement, even for very large numbers of revolutions.

Parameters:

  • revolutions – The number of full revolutions

  • radian_offset – The offset from the given number of full revolutions. Note that this is usually between 0 and 2*M_PI, but callers should not assume this.

void set(double radians)

Sets the field to a given double value (in radians). Note that double precision floating point numbers cannot represent the same angular resolution at very high magnitudes as they can at lower magnitudes.

void set(int64_t revolutions, float radian_offset)

Sets the field to a given integer number of revolutions and a floating point offset from this number of revolutions. The offset does not specifically need to fall within a certain range (i.e., can add more than a single revolution to the integer value), but should be kept relatively small (e.g., below 10,000) to avoid potential loss of precision.

void clear()

Removes any currently set value for this field.