Remove spectator players' cameras when teleporting

[lucyydotp]

This fixes #13473 by mirroring vanilla behaviour.

[masmc05]

If an event changes the camera to a different new entity the teleport will still be broken, not sure but I think for any spectated entity you should cancel the teleport

[Doc94]

i think this can just be replaced with the this.getHandle().setCamera(this.getHandle());
i test for example the cancel teleport event and is not broken if you update the camera.

[lucyydotp]

Good point, I'll change that to check for any entity.

i think this can just be replaced with the this.getHandle().setCamera(this.getHandle()); i test for example the cancel teleport event and is not broken if you update the camera.

Would that not still change the camera even if the teleport is cancelled?

[lucyydotp]

Actually, how can the event change the camera? PlayerStopSpectatingEntityEvent is immutable, except for being cancellable. I'll update the check regardless but I don't think it will meaningfully change the behaviour

[Doc94]

Good point, I'll change that to check for any entity.

i think this can just be replaced with the this.getHandle().setCamera(this.getHandle()); i test for example the cancel teleport event and is not broken if you update the camera.

Would that not still change the camera even if the teleport is cancelled?

In teory but maybe the cancel state already manage that, like say you can test that behaviour but i dont find issue in cancel with the setCamera called

[Doc94]

ref: Doc94@0661918

[lucyydotp]

ref: Doc94@0661918

This breaks for me:

• Cancelling PlayerStopSpectatingEntityEvent lets the broken teleport happen
• Cancelling PlayerTeleportEvent kicks me off the entity I'm spectating without teleporting me anywhere

[Doc94]

ref: Doc94@0661918

This breaks for me:

• Cancelling PlayerStopSpectatingEntityEvent lets the broken teleport happen
• Cancelling PlayerTeleportEvent kicks me off the entity I'm spectating without teleporting me anywhere

that two then also happen using teleport command and mess with events too no?

for the PlayerTeleportEvent make sense because first dismount/cancel-spect and then teleport then i feel its expected
for PlayerStopSpectatingEntityEvent then can be good check if this and then teleport (like if the camera really change later or make the camera return a bool)

[lucyydotp]

Oh that's a very good point actually, I hadn't considered that. I don't think that behaviour makes much sense regardless of where it's coming from - potentially another paper bug? ServerPlayer#teleportTo has a setCamera param which does the same as this PR but doesn't check for event cancellation, would it be worth me patching that too while I'm there?

[Doc94]

hmm im calling the expert in teleportations thing here... @Owen1212055
but i think just fix the api method with the camera can be ok?

[Owen1212055]

It looks like in most cases (except one) where camera is reset it uses setCamera(self), so you may want to setCamera(this.getHandle())

[Owen1212055]

This kind of prompts additional conversation, but we may want to instead just have some kind of boolean on the set camera to ignore the canceling of those events. As there is a lot of places where this can occur and I don't really think we handle this logic at all (and instead just allow them to be teleported back a tick later or whatever)