[FIX] Fix fog race condition crash on page reload

[willeastcott]

Summary

• Fix crash when viewport renders before scene settings are loaded
• Simplify viewport initialization by removing unnecessary sceneSettingsObserver parameter passing

Details

Fixed a race condition that caused a TypeError: Cannot read properties of undefined (reading 'toUpperCase') crash. This occurred when:

1. User has "Show Fog" enabled in Editor Settings
2. Scene has fog type set to something other than "none"
3. On page reload, the viewport renders before scene settings data arrives from the server
4. sceneSettings.get('render.fog') returns undefined, which crashes the engine

Changes

• Added nullish coalescing fallback (?? pc.FOG_NONE) when reading fog settings in viewport-application.ts and camera-preview.ts

• Simplified ViewportApplication by calling editor.call('sceneSettings') directly instead of storing and passing sceneSettingsObserver through the constructor

• I confirm I have read the contributing guidelines

[Copilot]

Pull request overview

This PR fixes a race condition crash that occurred when the viewport rendered before scene settings were loaded on page reload. The fix adds defensive null checks using nullish coalescing and optional chaining when reading fog settings, and simplifies the code by removing unnecessary parameter passing.

Changes:

• Added nullish coalescing fallback (?? pc.FOG_NONE) with optional chaining for fog settings access in viewport-application.ts and camera-preview.ts
• Removed unnecessary sceneSettingsObserver parameter passing from viewport.ts constructor
• Replaced stored sceneSettingsObserver property with direct editor.call('sceneSettings') calls

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/editor/viewport/viewport.ts	Removed sceneSettingsObserver variable and parameter passing to simplify initialization
src/editor/viewport/viewport-application.ts	Added optional chaining and nullish coalescing for fog settings, removed sceneSettingsObserver property
src/editor/viewport/camera/camera-preview.ts	Added nullish coalescing for fog settings fallback

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