update-ui

name	update-ui
description	Toolkit for modifying UI components in Split Shift—HUD elements, menus, canvases, buttons, and overlays. Use when working on any visual interface element.

Update UI Toolkit

Core Architecture Context

• HUDManager: Controls the on-screen HUD (health bars, stress meter, character indicator). Updated via PlayerManager.Instance.UpdateHUD().
• Canvas System: Multiple canvases exist—PauseCanvas, GameOverCanvas (LossCanvas variants), WinCanvas, LoadingStartCanvas, and MenuCanvas.
• GameManager: Manages canvas instantiation and Time.timeScale for pause/game-over states.
• TextMeshPro: All text rendering uses TextMeshPro. Never use Unity's default Text component.

Strict Coding Constraints

• Encapsulation: NEVER use public fields for Inspector variables. Strictly use [SerializeField] private.
• Naming: All private fields MUST use the _camelCase prefix.
• Canvas Safety: Never destroy canvases directly—use GameManager.Instance.CleanupBeforeReload() or Destroy(tempCanvas).
• Time Scaling: Always set Time.timeScale = 0 when showing overlays (pause, game over) and Time.timeScale = 1 when dismissing them.
• Scene Reloads: When reloading the scene, set GameManager.Instance.isRestartingScene = true to skip loading screen effects.

Execution Steps

1. Identify Canvas Type: Determine if the UI is a HUD element (in-scene), menu (main menu), overlay (pause/game-over), or result screen (win/loss).
2. Locate Manager: Check if the UI is controlled by HUDManager, GameManager, PauseCanvas, GameOverCanvas, WinCanvas, or LoadingStartCanvas.
3. Implement Changes: Add/modify UI elements, bind events to buttons, update text/sprites.
4. Wire Events: Ensure button OnClick() events are properly connected to manager methods (e.g., Restart(), Resume()).
5. Refactor Tech Debt: Auto-convert any public Inspector variables to [SerializeField] private _camelCase. Update all references.
6. Validate: Test that the UI appears/disappears at the correct game states and doesn't leave orphaned GameObjects.

Common Patterns

HUD Updates

// Always update HUD through PlayerManager
PlayerManager.Instance.UpdateHUD();

Showing an Overlay Canvas

Time.timeScale = 0;
tempCanvas = Instantiate(canvasPrefab);

Dismissing an Overlay

Time.timeScale = 1;
if (tempCanvas != null) Destroy(tempCanvas);

Scene Restart

GameManager.Instance.isRestartingScene = true;
SceneManager.LoadScene(SceneManager.GetActiveScene().name);

Anti-Patterns to Avoid

• ❌ Directly modifying HUD elements without going through the proper manager.
• ❌ Instantiating multiple canvases without tracking/cleanup.
• ❌ Forgetting to reset Time.timeScale when dismissing overlays.
• ❌ Using Unity's built-in Text instead of TextMeshPro.
• ❌ Leaving public fields for Inspector-exposed values.