I’ve been having a lot of trouble debugging my first person game because there is no separate debug viewport (unlike, say, in Unity or a few other engines) that tracks what’s happening in realtime.
“But you can eject from your player character to go into an editor view!” I hear you say… except that you can’t actually control your character when it’s not being possessed (which makes sense), so at best you get a view of a fail state, but not what happened to get there. When I run into a problem that a collision isn’t triggering the way it should after I do X and then Y in special circumstances Z, there’s no way for me to see what the engine is doing while it actually happens (and I’m giving the relevant inputs). Its usefulness wouldn’t be limited to debugging first person problems.
The debug viewport wouldn’t even have to have all the bells and whistles of the main game viewe (and even if it did, it’s a debug viewport, so framerate really isn’t the first priority), just something we can set up and move around in to figure out what’s happening under the hood without having to eject all the time, leaving your player standing around like a storefront dummy.