Group Calls (WIP)

[robertlong]

Starting to implement group calls in Element. Will update these PR notes soon. This is following the work on Group Calls in matrix-js-sdk matrix-org/matrix-js-sdk#1902

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[SimonBrandner]

Suggested change

	export function GroupCallView({ groupCall, pipMode }: IProps) {
	const GroupCallView: React.FC<IProps> = ({ groupCall, pipMode }) => {

We tend to this rather than the other thing, you'll also need to export by default because of the dumb way component.index works

[SimonBrandner]

There is one outstanding issue I see with this atm. The use of the GroupCallParticipants to display video elements is quite concerning to me. I find this solution quite ugly and not very scalable. I would very much prefer to stick to the current model of using CallFeeds and VideoFeed and AudioFeed components.

The are multiple reasons for this:

• Using GroupCallParticipants feels like saying each participant is only sending one feed which isn't true
• Using CallFeeds matches the current way of doing things and allows us to reuse already existing code
• CallFeeds are screen-sharing friendly
• CallFeeds are SFU friendly - with an SFU one GroupCallParticipant might be sending a bunch of streams, each one represented by a CallFeed (and corresponding components)

To be clear, I am not saying GroupCallParticipant should be removed or anything along those lines, I just think CallFeeds are better suited for being consumed by components for displaying video and playing audio

[SimonBrandner]

Replaced by #6848

[robertlong]

Thanks @SimonBrandner for letting me know about the CI integration being dependent on branch name 👍