clarified semantics currently supported with TrafficUpdate

[clemenshabedank]

Signed-off-by: Habedank Clemens qxs2704@europe.bmw.corp

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Clarifying semantics after feedback from SETLevel project. The semantics for other potential use cases, e.g. multiple TrafficParticipants packaged in one model would need to be elaborated and specified (OSMP + OSI) and are therefore currently not supported. A trailer seems unproblematic in this regard, so keeping the field repeated is possible.

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[clemenshabedank]

By reading through the documentation of trailer_id I felt it could be made more clear that a trailer ID is basically a MovingObject ID. Any opinions on that? Maybe @DerBaertige @thempen

[caspar-ai]

@clemenshabedank thanks for that change, think it looks good.

My only suggestion would be that there are two things to be explained:

1. That TrafficUpdate is designed to only be used for a single traffic participant within a top level message
2. Given that, why is update a repeated field

You change does a good job of capturing (2), but there isn't anything explicitly that states (1), perhaps we should add something in the header, around line 15?

[clemenshabedank]

@caspar-ai thanks I hope e374ebc makes it clearer. Please feel free to make changes.

[caspar-ai]

Looks good to me, thanks!

[stefancyliax]

OSI CCB:

• Since we are a small CCB today, we want to take this topic into the next CCB. From our side, this is ready to merge. @pmai @clemenshabedank @LukasElster @stefancyliax

[ThomasNaderBMW]

Maybe the trailer design should have been otherwise because its confusing. It is how it is now, but for this message it clarifies a lot. So +1

[kmeids]

CCB Output 21.07.2021

1. @max-rosin to check the documentation.
2. @pmai will merge when @max-rosin is done.

[max-rosin]

I would recommend against capitalizing words for emphasis.

Suggested change

	// to update data of exactly ONE traffic participant, optionally with an attached
	// to update data of exactly onetraffic participant, optionally with an attached

Otherwise, the text is good.

[clemenshabedank]

@max-rosin Sure, it's fine for me. But two words please ;) Am I supposed to do it or will you do the change?