HUD system

[EternalQ]

HUD system summary

com.cleanroommc.modularui.hud renders ModularUI panels directly over the game world (or over/under
an open GuiScreen), reusing the normal widget-tree/theme/layout pipeline. A HUD element is
display-only: no mouse/keyboard input, no hover/focus/drag - only draw() sees an updated mouse
position.

How it works

A HudElement owns a private ModularScreen built from a HudContext (no-op onFrameUpdate(), so
no hover/focus/drag logic runs) and a throwaway HudWrapper GuiScreen used only to satisfy
ModularScreen#constructOverlay's contract - neither is public API.

HudManager (started once via HudManager.init(), already wired in ClientProxy) hooks:

• RenderGameOverlayEvent.Post - draws while no GuiScreen is open (visibleInWorld).
• GuiScreenEvent.DrawScreenEvent.Pre/.Post - draws under/over an open GuiScreen
  (visibleInGui(visible, isOverGui)).
• ClientTickEvent - ticks registered elements.

HudElement hud = new HudElement("mymod", ctx -> {
    ModularPanel panel = new ModularPanel("status").size(100, 20).pos(5, 5);
    panel.child(new TextWidget().text(IKey.dynamic(() -> "Current time: " + System.currentTimeMillis())));
    return panel;
});
HudManager.register(hud);
// HudManager.unregister(hud) / .clear() to stop drawing+ticking, e.g. on log-out

enabled(boolean) toggles an element entirely (skips ticking too); renderPriority(int) orders
overlapping elements (higher draws on top).

Changes (including fixes for my chat mod)

• HUD system added (HudElement, HudManager, HudContext, HudScreen, HudWrapper).
• Text field scroll/cursor fix: the cursor and just-typed text were clipped out of view once
  typing past a field's visible width. Fixed by measuring scroll in the same coordinate space as the
  cursor (plus a scrollEdgeMargin) and widening the cursor quad so it still rasterizes at a
  scrolled/clipped edge.
• Platform.setupDrawFont() now enables GL_BLEND: previously FontRenderer wrote fully opaque
  pixels regardless of a color's alpha channel, so fade-out/ghost-text effects had no visible effect.
• InternalWidgetTree.drawTreeForeground now skips disabled widgets: brings it in line with
  drawTree/IWidget#drawForeground's own documented contract - a disabled widget's foreground/tooltip
  should not render, but it still did.
• Lighting/darkening fix: having a HUD element visible under/over an open GuiScreen (the default)
  made the whole game - world and every GUI - render visibly darker, permanently, until restart. Cause:
  RenderHelper.enableStandardItemLighting() bakes GL_LIGHT0/GL_LIGHT1 positions relative to
  whatever matrix is active when it's called; called from a HUD overlay's own transform stack (as
  ModularScreen.drawScreen()/drawForeground() always did, for every screen), those positions came
  out wrong, corrupting lighting for everything drawn afterward. Fix: both methods now skip
  RenderHelper.enableStandardItemLighting()/GlStateManager.enableLighting() entirely when
  isOverlay() is true (HUD screens never render lit 3D items, so nothing is lost). Do not remove this
  guard or call those methods from HUD-drawn code.

Checklist

• I have tested this PR in DevEnv
• I have tested this PR in Fullpack - woks fine in 2.9-beta2
• This PR is in compliance with the GTNH AI Policy - I'm not sure. A lot of the code was indeed generated (especially the comments and documentation, which I'm too lazy to write myself), but I supervised and guided every step.
• This PR requires another PR in order to merge

[EternalQ]

Example of HUD
https://github.com/user-attachments/assets/80da751d-3ac0-47ea-9c89-f2695ce745bd

[brachy84]

Add the param to the existing private ctor and add overloads for the public ctors which just call this(...)

[brachy84]

Dont inline code blocks

[brachy84]

Why is this needed? Why is widget padding not enough?

[brachy84]

Also either write SHORT code comments yourself or dont write them at all. NOBODY is reading those books.