Editor: Added submenu navigation

[ycw]

Related: #28284

This PR added submenu navigation

• Added box-shadow to menu and submenu for more popover-ish
• Localized the submenu titles
• Can close Editor: Improve menubar visual #28284

submenu+shadow.en.mp4

Preview: https://raw.githack.com/ycw/three.js/editor-submenu/editor/index.html

[mrdoob]

Looking good!

[mrdoob]

Actually, sorry... Instead of "Geometry" it should be "Mesh" 🙏

[ycw]

done :D

[mrdoob]

Thanks!

[mrdoob]

Few more tweaks: 9f81b72 cc9a249 c857c1e cf29a58 3468145 65c4c27 c5ae348 b2e1389

[mrdoob]

Screen.Recording.2024-05-07.at.5.37.25.PM.mov

[ycw]

what about

File 
  New
  Example >     <<<<<< put examples here
  Import
  Export >

?

[mrdoob]

Good idea!

I think I would then add a couple of UIHorizontalRules.

File 
  New
  ---
  Examples >
  ---
  Import
  Export >

[ycw]

Good choice.

[mrdoob]

While looking at this I wanted to see how it would look like if we listed all the formats...

Way too intimidating...

[mrdoob]

Just found out about <input>'s accept property: a131775

That way the user can tell what files can be imported.

Before:

After:

[ycw]

Just found out about < input > 's accept property: a131775

Good, and remember that accept list must be in sync with Loader.js #28295 (comment)

[ycw]

what about

File 
  New
  Example >     <<<<<< put examples here
  Import
  Export >

?

Updated to

File
  New Project >       << all examples goes here
  ---
  Import
  Export >

see #28325