- update all msgs to be directly compatible with ROS2
- microdds_client improvements
- timesync
- reduced code size
- add to most default builds if we can afford it
- lots of other little changes
- purge fastrtps (I tried to save this multiple times, but kept hitting roadblocks)
* Changed sitl_gazebo to the advanced liftdrag plugin fork.
* Added advanced plane and its associated parameters to PX4. Also tweaked one of the plugins to fix a compilation error (upcasting from float to double).
* Switched gazebo back to main branch, to avoid merge conflicts.
* Change simulator bridge back to what it was in main branch
* Changed sitl_gazebo to match the PX4 main branch's (commit hash b968405)
* Changed SimulatorIgnitionBridge to match most recent main.
- for convenience merge px4_sitl_ign into px4_sitl_default, but allow simulator_ignition_bridge to quietly skip inclusion if ignition-transport isn't available
- simulator_ignition_bridge only try setting the system clock in
lockstep builds
- this simplifies usage and CI system dependencies
- new modules/simulation directory to collect all simulators and related modules
- new Tools/simulation directory to collect and organize scattered simulation submodules, scripts, etc
- simulation module renamed to simulator_mavlink
- sih renamed to simulator_sih (not a great name, but I wanted to be clear it was a simulator)
- ignition_simulator renamed to simulator_ignition_bridge
- large sitl_target.cmake split by simulation option and in some cases pushed to appropriate modules
- sitl targets broken down to what's actually available (eg jmavsim only has 1 model and 1 world)
- new Gazebo consistently referred to as Ignition for now (probably the least confusing thing until we fully drop Gazebo classic support someday)
