Module menu 

Menu system abstractions for JRPG engine.

This module defines:

• MenuProvider trait — game-data provider for menu definitions (titles, options, layouts). Implemented by the data crate.
• MenuSystem<M> struct — stateful menu controller that manages cursor position, scroll offset, input handling, and rendering.
• MenuInput / MenuAction — input abstraction and action results.
• NamedMenuInputSource trait — platform-level input conversion.

Design

The menu system is data-driven: the provider supplies static layout and option data, while MenuSystem owns the runtime state (cursor, scroll, open/closed). Rendering uses the Painter trait, so menus work identically across pixel and recording backends.

Structs

BorderStyle

A configurable 9-slot border for menus. Each slot references a tile index in the currently active tileset. Editors can swap these to change the visual style without code changes.

CursorStyle

Cursor indicator style for menus.

EdgeInsets

Padding inside a menu container (in tiles).

MenuConfig

Rendering-level layout for a menu. Describes where and how a menu is drawn on the 160×144 canvas.

MenuInput

Abstract menu input, decoupled from any specific platform or key binding.

MenuLayout

Static layout descriptor for a menu.

MenuOption

A single option in a menu list.

MenuSystem

Stateful menu controller that owns cursor position, scroll offset, and open/closed state.

Enums

CursorAnchor

Cursor anchor point relative to a menu entry.

MenuAction

Outcome of MenuSystem::handle_input.

TileSlot

Position slot in a border tile set. Used by editors to identify which border tile to swap.

Traits

MenuProvider

Provider of static menu definitions (titles, options, layouts).

NamedMenuInputSource

Trait for converting platform-specific input (keyboard, gamepad, touch) into abstract MenuInput.