gz-sim: Python interfaces

[azeey]

Setup

• Os: Ubuntu Jammy
• BuildType: Binary

Links

• Live
• Source

Checks

• Instructions work
• Images (if there are any) match the result

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You can find the code used to generate this test case here

[mjcarroll]

I believe the following only works with a merge-install with colcon, correct? We are advising to do that iirc, but could still be overlooked.

export PYTHONPATH=$PYTHONPATH:<path to ws>/install/lib/python

[mjcarroll]

My output looks slightly different. @azeey is this just a difference in computers or has something actually changed in the way that the python system works:

[Msg] Loading SDF world file[/home/ahcorde/gz_fortress/src/ign-gazebo/examples/scripts/python_api/gravity.sdf].
[Dbg] [Physics.cc:789] Loaded [gz::physics::dartsim::Plugin] from library [/home/ahcorde/gz_fortress/install/lib/gz-physics-5/engine-plugins/libgz-physics-dartsim-plugin.so]
[Dbg] [SimulationRunner.cc:909] Loaded system [gz::sim::systems::Physics] for entity [1]
[Msg] Loaded level [3]
[Msg] Serving world controls on [/world/gravity/control], [/world/gravity/control/state] and [/world/gravity/playback/control]
[Msg] Serving GUI information on [/world/gravity/gui/info]
[Msg] World [gravity] initialized with [default_physics] physics profile.
[Msg] Serving world SDF generation service on [/world/gravity/generate_world_sdf]
[Msg] Serving world names on [/gazebo/worlds]
[Msg] Resource path add service on [/gazebo/resource_paths/add].
[Msg] Resource path get service on [/gazebo/resource_paths/get].
[Msg] Resource paths published on [/gazebo/resource_paths].
[Msg] Found no publishers on /stats, adding root stats topic
[Msg] Found no publishers on /clock, adding root clock topic
[Dbg] [SimulationRunner.cc:524] Creating PostUpdate worker threads: 2
[Dbg] [SimulationRunner.cc:537] Creating postupdate worker thread (0)
AddSystem1
World entity is  1
Gravity  0 0 -9.8
Entity for falling model is:  4
AddSystem2
iterations  1000
post_iterations  1000
pre_iterations  1000

[azeey]

testFixture.py is not using python system plugins. It's using the python bindings for the TestFixture class. I'm guessing it's just an out-of-order printing issue. I get the same output as you on both Harmonic and Garden.

[mjcarroll]

Should we update the output to match or is this fine?

[azeey]

I tried it on two different computers and got the python messages after the last "postupdate worker thread" message, so maybe we should change it.

[azeey]

gazebosim/gz-sim#2157

[Voldivh]

Closing this since PR have been merged.