Thursday, 23 June 2011

Gating player progress

Player gating is a term that is used to describe the various methods of halting a players progress through a map.
Without them players could charge through every encounter like an 8 year old in a particularly boring museum.

Player gating can be a seriously frustrating business. How do I make sure the player kills all the bad guys before the move on?

Its a simple enough problem however trying to make the reasons for player gating plausible to the game world can be a real problem. Heres some of the various methods Ive seen used.

The Puzzle Gate

The simplest form of gate. Solve the puzzle to access the exit.
Think about the breezeblock seesaw puzzle near the beginning of HL2.

The Weapon Gate

The player must obtain a new weapon in order to break through a barrier.
This is a great way to ensure the player doesnt skip a new weapon that they will need later in the map.

HL2:EP1 Pistol Weapon Gate

The NPC Break In Gate

Once the action has finished in the area, a previously blocked route is unblocked by a new enemy NPC being introduced, normally by smashing or blasting through the door.
The slightly overused combine door lock blasts in HL2:EP1 are ax good example of this. The nice tuing about this method is that it keeps the action going.

HL2:EP1 Break In Gate

The Slow Mover Gate

The player activates the gate opening mechanism but it take a very long time for the gate to open. While waiting the player normally has to deal with a slew of enemies and survive long enough to escape.

This is seen over and over again in the Left 4 Dead games and suits the play style well. The other typical scanario is activativing THE SLOWEST LIFT IN THE WORLD!

The crane scene in the Left 4 Dead: Dead Air campaign is a great example of a slow mover gate...

The only downside for SP is that its a timed event, which means that the player can escape without clearing out all the enemies.. thats probably mostly OK though.

The Death Throw Gate

As an enemy dies it's last actions are scripted and open up a new route for the player.
This one is tough to pull off because the NPC once defeated has to perform a number of scripted actions before they finally shuffle off the mortal coil. It stretches the imagination a little but can be more plausible for flying enemies or really big boss npcs that can fall in a certain direction to smash through a wall or something.

Mate Opens Gate

A friendly NPC appears and opens the route forward for you. This will require NPC scripting and can be fun if its done well but its not my preference. The less help the player gets from NPCs the better in my opinion.

Examples of this are prolific in HL2 with Alex hacking combine terminals over and over again.

The Eye Candy Gate

A jaw dropping moment for the player to watch and enjoy that open up a new route for the player. Think the plane crash in the L4D Dead Air campaign. Will take you ages to build but may be well worth it as you know the player will be fully focussed on all your hard work.

The Astounding Dead Air Plane Crash

Let me know if I have missed any methods... or if youve seen any other really cool ways to gate the player.

Falling Into Player Gating Traps

Heres a good example of how a mapper can fall into a player gating trap.

In my map Ep2_aquaduct_4-5 the whole sequence of events begins with the player turning a valve to make water rise in order for them to reach the first level of the chamber.

In order to add some necessary action to the early part of the map I had a nice firefight going on with combine on the higher levels of the chamber shooting down onto the player.

I dont want to lose that but how can I prevent the player from turning the valve and making the water rise before the attacking combine are dead.

I tried having the water rise anyway but the combination of the player having to swim whilst being fired upon was too annoying for playtesters and just wasnt any fun.

In the end I had to settle for a rather unrealistic approach. The combine dont attack until the player turns the valve (at which point the sound of rushing water can be heard) but the water level doesnt rise until the combine are all dead.
You could explain this away as it simply took that long for the water to rise but playtesters also commented that it seemed to take forever for the water level to begin rising...

I can think of no other way that the death of the combine could realistically provide access to the valve..

Heres a link to the map if you want to see for yourself how this works...

Here's the link:

1 comment:

Anonymous said...

Heya Aazell

Followed ya link here from the snarkpit.
I haven't had a chance to look at your map yet but regarding your gating problem...

One option is to have the valve in a small maintenance room behind a secure door at the players level. Once X number of enemy on the higher levels have been dispatched, one more enemy opens the door and exits the room containing the valve.
The player is then free to enter this room and turn the valve triggering the rise in water at whatever speed you want.