Developer UI Panels HUD

Build panels, HUD rows, and Hub entries the supported way. (Oxide equivalent: “CUI library”.)

Layer model (GregUILayerManager)

Background(-1000) < HUD(0) < Panel(1000) < Dialog(2000) < Overlay(3000) < Tooltip(4000) < Notification(5000). The Mod Hub lives in Dialog; your panels in Panel; the key bar in HUD. Resolve roots via GetLayerRoot(type) / AddToLayer() — never parent to game canvases directly.

Panels: the canonical recipe

IMGUI OnGUI is stripped — use UIToolkit via GregPanelBuilder (src/gregCore.UI/GregPanelBuilder.cs):

GregPanelBuilder.Create("Title")
    .SetSize(500, 600)
    .Build()                       // Layer.Panel by default
    .AddHeadline("…") .AddLabel("…")
    .AddButton("Do it", OnDo)      // + AddSecondaryButton / AddToggle / AddSwitch
    .AddSlider("…", 0, 100, 50, OnSlide)   // + AddDropdown / AddInputField
    .AddSpacer(8) .AddSeparator()
    .Show();                       // .Hide() / .Toggle() / .Destroy()

Three mandatory companions (IL2CPP realities, see docs/modding/ui-panels.md):

1. Clicks — register Button.RegisterCallback<ClickEvent> and the per-frame worldBound fallback (GregClickRouter.RouteClicks, 500 ms dedup, Screen.height - y flip). There is no EventSystem.
2. Fonts — apply GregFontLoader.DefaultUGUIFont (null-tolerant; Toolkit default renders invisible otherwise).
3. Input lock — GregMenuOptions{LockCamera, LockMovement, LockInteract, ShowCursor, Draggable, SlideFromRight, PanelWidth} + GregMenuRegistry.SetOpen(menuId, open); ignore toggles while Pause/Escape/Options canvases are open.

GregPanel.GetOrCreate / RebuildContent / TickAll (0.28 s slide-in, docked right, draggable handle) + GregUIStack, animations, theme, tooltips, and GregNotificationManager cover the rest.

Hub + HUD wiring (one call each)

GregMenuBinding.BindToggle("my_mod.main", ToggleFn, () => isOpen);
GregMenuBinding.Report("my_mod.main", isOpen);   // keep Hub state truthful
GregMenuRegistry.RegisterOpener("my_mod.main", OpenFn);
GregMenuRegistry.RegisterCloser("my_mod.main", CloseFn);
GregHudRegistry.Register("my_mod", "M", "My Mod (M)");  // right-edge key bar

The F1 Hub (GregModHub) groups GregModRegistry.All() by mod.Menus[] vs GregMenuRegistry.Snapshot(); honest buttons only (Close iff HasCloser). Settings jump via GregSettingsHub.FindTabForMenu(...).

Lua tablets / widgets (handles)

Flat globals returning string handles (pnl_<guid12>), not greg.ui.*:

local id = tablet_open("My Tablet")        -- "" = failed
local w = widget_open("Mini", 100, 200)
panel_add_label(id, "Hello")
panel_add_section(id, "Group")
panel_add_spacer(id, 8)
panel_add_button(id, "Repair", function() greg.server.repair_all() end)
panel_add_toggle(id, "Enabled", true, function(v) ... end)
panel_add_slider(id, "Speed", 0, 10, 5, function(v) ... end)
panel_toggle(id)      -- -> new visibility
panel_visible(id)     -- -> bool
panel_close(id)       -- -> bool

Also: greg.ui.notify(msg, seconds?), greg.ui.log_*, greg.ui.register_mod_config_tab(tab_id, label, builder_fn). C# settings tabs: GregSettingsHub.RegisterTab with AddToggle / AddSlider / … (MelonPreferences-backed).

Checklist

• Panel opens/closes from both its hotkey and the F1 Hub.
• Clicks work (callback + router fallback) at multiple resolutions.
• Fonts visible; input locks only while open; cursor restored after.
• HUD row registered once per mod; Hub shows Open or Close truthfully.