Question about Editor Programming

Development Programming & Scripting
1

Hello fellow UE4 Programmers,

I have some Questions regarding Editor Programming. So far I got my Custom Editor Mode Working that draws a Box in the Viewport using FPrimitiveDrawInterface. Now I have a couple of questions:

  1. How do I draw a mesh using FPrimitiveDrawInterface ? Or what would be a good way to render a mesh in the editor viewport for my Custom editor? Think of the move widget as an example.
  2. Some Function that use FPrimitiveDrawInterface DrawDirectionalArrow require a FMatrix. How do I use those?
  3. How do I write Interactions for my custom editor mode? Like dragging an arrow inside the viewport. I tried finding my way arround in the LevelEditor code, but since it is so big it is really hard for me to understand.

Help is much appreciated!