Selecting an instance containing a batch of keypoint_id + class_id spams a warning: "not a mono-batch"

[jleibs]

Easy repro using the face_tracking example.

python -m face_tracking

then select any keypoint.

Text of the warning:

Processing frames: 691it [00:23, 27.51it/s][2024-05-16T13:16:52Z WARN  re_query::latest_at::helpers] Couldn't deserialize /reconstruction/faces/0:rerun.components.ClassId @ TimeInt(690)#17CFFA806598864D24D999916925D29D: not a mono-batch (length: 478)

Root cause

The cause of the problem comes from:

rerun/crates/re_data_ui/src/annotation_context.rs

Lines 97 to 99 in 692b6b6

	let class_id = ctx
	.recording()
	.latest_at_component::<re_types::components::ClassId>(entity_path, query)?;

We are using latest_at_component which depends on a mono-component, but the keypoint is an instance of a batch.

To fix this properly, we need to track the instance all the way through EntityDataUi and use it to look up the correct class-id.

Affects

0.15, 0.16

[jleibs]

In: #6359 we made this incrementally better by getting rid of the log spam

[emilk]

Looks like this issue is finally producing real problems:

• The viewer is querying ClassId wrongly, leading to warning in face_tracking example #3168

[emilk]

In fact, I'm closing this as a duplicate of #3168