Insert system plugins from the GUI

[chapulina]

Often users forget to load a necessary plugin into simulation. It would be handy if they could pick plugins from a menu or a browser window and attach them to entities at runtime.

The backend already supports loading systems at runtime. What's missing:

• A menu / browser window to choose system plugins
• A dialog to add configurations to the plugin (including what entity to attach to)
• A transport interface for the GUI to tell the server to load a new system

As a reference, Gazebo-classic's model editor supported adding model plugins:

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It's worth mentioning that GUI plugins can already be loaded from the top-right menu.

[mayman99]

If no one is working on this already, I could have a look at this and maybe at #1258 after.

[chapulina]

Thanks, @mayman99 ! Before starting the implementation, it would be good to draw a high-level schematic of how the plugin could work so we can iterate on that before writing any code.

I think it would also be good to start with a PR that adds just the transport interface, and subsequent PRs add the GUI.

[mayman99]

Thanks! @chapulina .
I'll be having a closer look at how the loading of plugins from the menu on top right works. The thing I so far don't have a concrete idea about is the transport interface, so if the backend already supports loading systems at runtime, why do we need a transport interface then? (I understand what the UserCommands class do, and that a plugin must inherit from it's plugin interface/interfaces-- but still having trouble connecting all together).

[chapulina]

if the backend already supports loading systems at runtime, why do we need a transport interface then?

Currently, systems can be loaded at runtime if they're attached to a model that's being spawned. But the idea here is to add a system to a model / sensor / visual which is already in simulation, or to the world itself. We don't have an interface for that yet.

I think the SimulationRunner could offer a transport service that accepts a message that contains msgs::Plugin + msgs::Entity and calls AddSystem accordingly.