airacingtech / autoware_auto_msgs

Forked from https://gitlab.com/autowarefoundation/autoware.auto/autoware_auto_msgs

This is a Tier4 forked version of autoware_auto_msgs

autoware_auto_msgs

Interfaces between core Autoware.Auto components.

Conventions

Comments

Add a comment to describe the meaning of the field.

Default Value

Prefer a meaningful default value. Otherwise, the field is uninitialized.

Optional parameters

There is nothing like std::optional in IDL, unfortunately. To accomodate the common use case of a fixed message where some variables are not always filled, add an additional boolean variable with a prefix has_ and a default value of FALSE.

Units

If a quantity described by a field has an associated unit of measurement, the following rules apply to determine the field name:

1. If the unit is as base or derived SI unit, do not add a suffix and assume the default from REP-103.
2. If the unit is a multiple of a base or derived SI unit, apply a suffix according to the table below.
3. If the unit is composed of non-SI units, apply a suffix according to the table below.

Only deviate from the SI units when absolutely necessary and with justification.

Quantity	Unit	Suffix	Notes
distance	meters	None
	micrometers	_um
	millimeters	_mm
	kilometers	_km
speed, velocity	meters / second	None	Use speed for scalar and velocity for vector quantities
	kilometers / hour	_kmph
acceleration	meters / second2	None
radial velocity	radians / second	None
time	second	None
	microsecond	_us
	nanosecond	_ns

Examples

The first alternative is recommended, the second discouraged:

1. float elapsed_time vs float_elapsed_time_s
2. float distance_travelled vs float distance_travelled_m
3. int32 time_step_ms vs int32 time_step
4. float speed_mps vs float speed

Minimal Example

struct Foo {
  @verbatim (language="comment", text=
    " A multiline" "\n"
    " comment")
  @default (value=0.0)
  float bar_speed;

  @verbatim (language="comment", text=
    " Another multiline" "\n"
    " comment")
  @default (value=FALSE)
  boolean has_bar_speed;

  @verbatim (language="comment", text=
    " Describe the time stamp")
  @default (value=0)
  int32 timestamp_ns;
};