uxmlib-hud

Overlays delivered through Paper's own player API — no packets, no NMS.

Sidebar

SidebarManager sidebars = new SidebarManager(Bukkit.getScoreboardManager());

Sidebar sb = sidebars.create(player, Text.mini("<gold><bold>Server"));
sb.lines(List.of(
        Text.mini("<gray>Online: <white>42"),
        Text.mini("<gray>Map: <white>spawn")));
sb.show();

sb.lines(...) diffs against what the player currently has and re-sends only the lines that changed. That is what makes it flicker-free: the usual approach clears and rewrites the whole objective every tick, and the client renders the gap.

Call it every tick with the same content and nothing is sent at all.

Titles

new Titles().show(player, Text.mini("<green>Welcome"), Text.mini("<gray>have fun"));

Title and subtitle, with the usual fade and stay timings.

Action bar

new ActionBarManager(scheduler, server)
        .show(player, Text.mini("<yellow>Saved!"), Duration.ofSeconds(3));

Sticky: the action bar clears itself after a couple of seconds, so a message that should stay for three has to be resent. The manager does that, and takes a duration instead.

It also arbitrates between callers — two features writing to the action bar at once produce a flicker otherwise.

Boss bars

new BossBarManager(scheduler, server)
        .countdown(player, Text.mini("<red>Event"), Duration.ofMinutes(1));

BossBarMode covers the four shapes:

RemainingTime formats the countdown text.

Tablist

new Tablist().set(player, header, footer);

Header and footer, per player.

Animation

TextAnimator drives per-tick text effects, with GradientText and ScrollingText as the built-in ones. UpdateBatch groups several HUD changes so they are sent together rather than as separate packets in the same tick.

Everything is per-player

Every type here takes a Player. There is no server-wide scoreboard state and no shared objective — which means two plugins can each show a sidebar without fighting, and a per-player value needs no special handling.

The cost is that a server-wide bar is a loop over players. UpdateBatch is there for exactly that.