Hi,
so I have an energy ball launcher which will launch a ball upon pressing a timer switch. I would like to make it so that there can be only one ball bouncing and another one can be launched after the first one has disappeared. I have studied the inputs and outputs, but the point_energy_ball_launcher entity does not have any useful output which would be fired upon ball self-destruction.
Any ideas?

Hmmm.
First idea is:
A huge trigger_multiple.
A filter_combine_ball_type.
Make the trigger see the ball on StartTouch.
StartTouch >> Disable button or related key trigger.
EndTouch >> Re-enable button or related key trigger.

For goodness sake, there was a similar topic about this made less than 2 weeks ago! Click Search at the top of the page once in a while!

calm down, I just didn't know what terms to search for
well, in the old topic there is a problem with automatic ball spawning, but I need to avoid multiple balls launched by the player by pressing the switch. See the difference?
Btw. the idea with trigger_multiple is not bad, but the trigger would have to fit all the space in the chamber and outside it (in the hallways and other chambers), which may consist of multiple brushes. I can't know where the ball gets in the game. Theoretically it can go anywhere in the map from the starting point to the launcher point

The best solution would be to make sure you can't get the energy ball into other parts.

The easy way would be to make one huge trigger brush that covers the whole map.