Godot: Reloading assets take very long when there's many of them

[KoBeWi]

Godot version:

3.2.2 beta4

OS/device including version:

Windows 10 x64

Issue description:

My project has a huge amount of assets (2k+ right now). I tend to rely on texture reloading to make tweaks on the fly. My problem is that the time between me saving changes to image and Godot starting to reimport it keeps increasing. Right now I try re-focusing editor for good -teen seconds before the changes are reflected in Godot.

AFAIK, Godot runs a periodical file scan on a separate thread and large amount of assets makes it take longer. Not sure what can be done about this. More threads or maybe it's possible to detect change of files in a different way. But this is a big problem for my workflow .-.

Steps to reproduce:

1. Have a project with LOTS of assets
2. Change some image
3. Focus editor and wait until the texture updates in the editor

[mbrlabs]

Filesystem notifications like FindFirstChangeNotificationW for Windows or inotify for Linux would probably the way to go. I actually tought that Godot was already using those APIs but apparently not.