Consider using separate thread for loading asset/project

[JamesTKhan]

When a larger project is loading all you see is a black screen until it has finished loading. Consider loading on a separate thread and displaying a loading message when opening a project. I suspect the main culprit is asset loading for the delay.

[JamesTKhan]

This is on the back burner. A major issue with implementing this is running GL calls on a separate thread. The asset loading process makes GL calls for somethings like model instances I believe. So the whole project/asset loading process would need reworking.

A solution may be adding two load methods. A pre-load method that handles all loading that can be done on another thread. Then the normal load method which will do all the GL calls on main thread.