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A brush that can take damage to a point, then call its triggers.

A brush that can take damage to a point, then call its triggers.

I find this entity to be more reliable than the func_breakable when it comes to defining the amount of damage it can take. It can also be used to create an object (group of objects) that can o­nly be broken from o­ne side.

As an example of how this can be achieved, I have created this tutorial:

The entities that will be used are:

func_trigger_brush
func_wall
info_notnull
environ_chunk_spewer

1. Create a tunnel, doorway, or something that you wish to have access through from o­nly o­ne direction. I created a hallway.

2. Place a brush in front of the entrance that will be destroyed by the player for access and turn it into a func_trigger_brush.
Give it a target of spewer.

3. Place an environ_chunk_spewer o­n the other side of the door. This will be used to create the effect that a lot is being broken to gain access.
Give it a targetname of spewer.
Give it a target of chunknull1.
Give it a count of about 20. This will cause it to throw about 20 chunk pieces.

4. Place an info_notnull in the location where you want the debris from the chunk_spewer to fly. I placed it in the area that the player will be standing.
Give it a targetname of chunknull1.

5. On the other side of the hallway, place a func_wall to block players from access. This will be a wall before the destruction of the trigger_brush, and will disappear after the destruction of the trigger_brush.
Give it a targetname of spewer which is the same name as the spewer itself. This means that when the trigger_brush is destroyed it will fire the chunk_spewer and the func_wall at the same time.
Check the flag for START_ON to make the wall present when the level is started and check the flag for TRIGGER_SPAWN to make the previous flag work. They require each other to work.

That should do it.