Add note lock function to beatmap editor

[cdwcgt]

Add a new property to BlueprintContainer to control whether the current selection can be moved.

this editor note lock behaviour consistent with stable by preventing drag movement of selected hitobjects in both the compose area and the timeline, including start time changes from timeline dragging.

osu.development.-.Yamamoto.Mineko.-.Rinne.frozz.Reincarnation.osu.2026-03-11.17-45-57_x264.mp4

[bdach]

Kinda weirded out by how this "locks positions and times of objects" but you can reverse or rotate or resize objects just fine. Therefore by extension moving them.

[cdwcgt]

Indeed, this feature only restricts the movement of objects; in the stable version, this feature exists specifically for adding sound effects (additional hitsound I think).
Some mapper have mentioned this to me, which has led me to consider adding this feature in a similar way to stable.

The stable's note lock doesn't restrict any shortcut keys or even directly adjust the slider's control point; it simply prevents the note from being dragged.

[bdach]

I question the usefulness of this for hitsounding as things stand because lazer does not have behaviours that stable does wherein you can select parts of sliders in the composer. On the other side, lazer hitsounding does not really require interacting with the composer that much other than to select objects (and even that is optional if you use the timeline pink pieces). Also the threshold for object drags is higher than stable too.

Now people want to both decrease the drag threshold, as well as to be able to select parts of sliders in the composer, but we're not there right now, and before we are, I really question how useful this feature is.

[peppy]

If it's just for hitsounding, I'd rather add a new tab/mode for that and call it as such. Maybe a second select tool. Rather than just blindly copying stable – especially calling it "note lock" when this is by definition also the name of a game mechanic.

[cdwcgt]

Yes, I largely agree with that view. If you really think this feature is unnecessary, just close this pr
At least it provides a way for those who have questions about this feature?