What is the open world 3D scene map editor?

Question

Game development

I made my game on Godot 3, made the basic content for filling the levels Houses, fences and other props - objects.
I am not satisfied with the scene editor built into godot, it is terribly uncomfortable + there is no terrain editor and the ability to color it if necessary. There is also no way to cut the mesh of the loaded terrain into chunks so as not to load all 100km by 100km into the player's computer memory. What alternatives are there do not offer blender to create the map. People who are far from 3d modeling will make levels, it is difficult to teach them how to use a blender.

A couple of things to choose from.
1. Preferably open source
2. Ease of operation
3. Output card format

For point 3. As I understand it, I will need to write a parser of this format. So that it converts the map into a scene with all triggers and active objects.

Answer 1

Valve Hammer