How I can disable Mouse Selection in Editor View for painting, editing an Object like in the Terrain Editor??
system
2
Calling this will do what you want 
public void OnSceneGUI()
{
HandleUtility.AddDefaultControl(GUIUtility.GetControlID(FocusType.Passive));
}
Spidyy
3
Hello there, nice for the necro. 
The most precise answer I can give to myself (yeah) is this :
// Retrieve the control Id
int controlId = GUIUtility.GetControlID(FocusType.Passive);
// Start treating your events
switch(Event.current.type)
{
case EventType.MouseDown:
//Treat your event
// ...
// Tell the UI your event is the main one to use, it override the selection in the scene view
GUIUtility.hotControl = controlId;
// Don't forget to use the event
Event.current.Use();
}
With this, you won’t be able to select anything in the scene while the object that lock the scene is selected. Change your selection in the hierarchy/project tab.
