mocap: add reset_counter, quality, estimator_type to odometry messages

[alireza787b]

Problem

The Mocap plugin's Odometry and VisionPositionEstimate messages are missing
fields that PX4's EKF2 can use for better sensor fusion. In the C++ implementation
(mocap_impl.cpp), these values are hardcoded:

• reset_counter: Hardcoded to 0 with // FIXME: reset_counter not set comments.
  EKF2 uses this to detect when the external estimator has re-initialized, so it can
  perform its own state reset rather than trying to fuse a discontinuous measurement.

• estimator_type: Hardcoded to MAV_ESTIMATOR_TYPE_MOCAP. For VIO users, this
  should be MAV_ESTIMATOR_TYPE_VIO. PX4's EKF2 can use this to select appropriate
  noise models.

• quality: Hardcoded to 0. PX4 can scale measurement noise based on this
  confidence metric — low quality = high noise = less influence on state estimate.

Changes

• Add MavEstimatorType enum (nested in Odometry) matching MAVLink's MAV_ESTIMATOR_TYPE
• Add reset_counter (field 9), estimator_type (field 10), quality (field 11) to Odometry
• Add reset_counter (field 5) to VisionPositionEstimate

Backward Compatibility

All new fields use proto3 defaults (0), preserving existing behavior:

• reset_counter = 0 → same as current (no resets reported)
• estimator_type = UNKNOWN (0) → C++ impl can default to MOCAP for backward compat
• quality = 0 → PX4 already handles 0 as "unknown quality"

This is a non-breaking, additive change. Existing users are unaffected.

Related PRs

• C++ implementation: mocap: wire up reset_counter, estimator_type, quality fields MAVSDK#2791 — wires up these new proto fields in mocap_impl.cpp
• MavFrame fix: mocap: fix MavFrame enum values to match MAVLink specification #396 — separate fix for MavFrame enum values (independent, can be merged in any order)
• Python example: examples: add vision odometry example MAVSDK-Python#820 — vision odometry example using the Mocap plugin
• MAVLink spec: ODOMETRY message (gimbal: add current attitude #331) defines reset_counter, estimator_type, quality

[JonasVautherin]

Thanks for the contribution! Looks fine to me, though I'm not knowledgeable regarding the mocap stuff. I'll let @julianoes be the judge of that 😇

[JonasVautherin]

I think we usually add the unit to the name:

Suggested change

	int32 quality = 11; // Estimate quality in percent (0-100), -1 for invalid/unknown.
	int32 quality_percent = 11; // Estimate quality in percent (0-100), -1 for invalid/unknown.

[alireza787b]

Good catch, thanks Jonas! Renamed to quality_percent (int32, -1 for unknown). Updated in the latest push.

[julianoes]

I tried this, and it doesn't build at all:

/home/julianoes/src/upstream/MAVSDK/cpp/src/mavsdk/plugins/mocap/mocap_impl.cpp: In lambda function:
/home/julianoes/src/upstream/MAVSDK/cpp/src/mavsdk/plugins/mocap/mocap_impl.cpp:170:35: error: ‘const struct mavsdk::Mocap::VisionSpeedEstimate’ has no member named ‘reset_counter’
  170 |             vision_speed_estimate.reset_counter);
      |                                   ^~~~~~~~~~~~~
/home/julianoes/src/upstream/MAVSDK/cpp/src/mavsdk/plugins/mocap/mocap_impl.cpp: In member function ‘mavsdk::Mocap::Result mavsdk::MocapImpl::send_odometry(const mavsdk::Mocap::Odometry&)’:
/home/julianoes/src/upstream/MAVSDK/cpp/src/mavsdk/plugins/mocap/mocap_impl.cpp:289:25: error: ‘MAV_FRAME_MOCAP_NED’ was not declared in this scope; did you mean ‘MAV_FRAME_LOCAL_NED’?
  289 |             mav_frame = MAV_FRAME_MOCAP_NED;
      |                         ^~~~~~~~~~~~~~~~~~~
      |                         MAV_FRAME_LOCAL_NED
/home/julianoes/src/upstream/MAVSDK/cpp/src/mavsdk/plugins/mocap/mocap_impl.cpp:301:79: warning: enumerated and non-enumerated type in conditional expression [-Wextra]
  301 |         odometry.estimator_type == Mocap::Odometry::MavEstimatorType::Unknown ?
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
  302 |             MAV_ESTIMATOR_TYPE_MOCAP :
      |             ~~~~~~~~~~~~~~~~~~~~~~~~~~                                         
  303 |             static_cast<uint8_t>(odometry.estimator_type);
      |             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~                      
ninja: build stopped: subcommand failed.

I'm not sure what to do with the frame stuff, especially because you are using MAV_FRAME_MOCAP_NED which has been deprecated according to https://mavlink.io/en/messages/common.html#MAV_FRAME_RESERVED_14.

I'm reverting this one and leave this to you to try to fix, given you have the context.