1. Unity Game Development
Unity Editor Extensions

2. Class overview Class 9 Revision CustomEditor MenuItem EditorWindow
Spawning Objects
Display Selected Objects
Advanced: RayCast Spawning
Advanced: Cube Spawning Objects

3. Revision Import & Setup Character Import & Setup Weapon
Import & Setup Animations
Bone rotations (Aiming)
Animation Masking
Inverse Kinematics (IK)
Advanced: Impact marking
Advanced: Aiming Camera

4. CustomEditor CustomEditor adds custom Editor UI
OnInspectorGUI to add functionality
GUILayout.Label
GUILayout.Button
EditorGUILayout.Colorfield
EditorGUILayout.Slider …
Execute actions in EditorMode

5. MenuItem MenuItem allows adding new entries in Toolbars
Execute action by clicking on it or by assigning a shortcut

6. EditorWindow EditorWindow allows creation of new Windows
Each Window can have unique functionality:
Procedural Generation
Renaming Objects
Spawning / Editing / Replacing objects
Generating complete Levels / Worlds …
Anything you can imagine! 

7. Spawning Objects Spawn Objects from selection
Selection.activeObject  Main active object as shown in inspector
Selection.gameObjects  Multiple objects selected using CTRL
Determine position and rotation using user input and store it :

8. Display Selected Objects
List selected objects by appending a string
Iterate over each entry of selected objects

9. Advanced: RayCast Spawning
Shoot RayCast from Random Position downwards
Instantiate Random Object on RayHit Position
Attach to empty Parent to reduce Object clutter in Scene Hierarchy

10. Advanced: Cube Spawning Objects
Ensure user has Cube selected
Access Bounds of Cube for Min / Max values

11. Q&A
Do you have any questions related to the topics mentioned?