Hi All
Decided to write a some articles about how real fruit machines work. In today's lesson, how fruit machines would control themselves, i.e. how decisions are made to pay a prize (or not).
BFG/Mazooma called them "compensators", Barcrest "stablisers", Ace/JPM "reflexes", Global "buckets" and 101 other permutations of the name. They all mean the same thing; essentially an amount of virtual money held in memory that the game uses to decide how much money we can give back to the player.
As I learned this stuff at the University of Mazooma, I called them "compensators", and that's what I'll use for this post.
How they work:
A game has a number of compensators, decided by the developer and/or mathematician responsible for the game.
Each game, we put the target % of the game into a compensator. So if the game is set to 80% payout, and you're on £1 a game, 80p goes into the compensator, and the other 20p is forgotten about.
A compensator is viewed from the player's perspective, that is, if the compensator is negative (hereafter referred to as -ve and positive as +ve) then the machine owes "the player" money - it has "underpaid". If the compensator is positive, the player owes the machine money - it has "overpaid".
As a side note, Barcrest worked the opposite way (from the machine's point of view - +ve being underpaid, -ve as overpaid).
We divide the compensator into "levels". The size of each level depends on various factors, again usually determined by the developer/maths person.
Let's see an example:
|
0------1------2------3------4------5------6 Compensator Level
|
+2500 +1000 +500 0 -500 -1000 -2500
So Level 3 is our midpoint - the compensator has ZERO money in it. But that doesn't mean you won't win. Quite the opposite.
Now we play some games, we stick £10 in and we win nothing. Now our compensator is -£8 (we took 80% of our stake, remember, the other £2 has evaporated!), we are there now in level 4 (between -£5 and £10).
But how do we decide if we're going to win? Easy. We use a chance table!
Let's see those same levels, but this time we're going to assign a % chance of something happening:
£2 nudge win chance:
|
0------1------2------3------4------5------6 Compensator Level
|
1 3 8 15 35 60 80 (% chance of winning)
As you can see, the chance of getting a win (or maybe of getting the feature) is adjusted depending on the level of the compensator.
Chance tables controlled almost every aspect of the game; the likelihood of getting nudges (losing or otherwise), the likelihood of holds, features, even to the point of choosing which music to play (the more money we have, maybe we play a more "intense" bit of music?).
When a win is given, assuming the player collects the win, we remove that money - £2 in this case - from the compensator (after which is still in level 4, now) and carry on. If they didn't collect the win (gambled, and lost) then we don't do anything - the machine still needs to get rid of that money at some point. When a compensator is at zero, the machine should be bang on payout %.
The money in a compensator has no relevence to the physical amount of money present in a machine - so if the hopper is full or empty makes zero difference to how likely you are to win (or not). So those urban legends about "the machine is backing" (i.e. coins going to cashbox) and therefore due to payout are nonsense, but we all had a good laugh about it!
Most AWPs, certainly ones we did, had 1 main compensator for general gameplay, and 1 for big wins. We would then divide the 80% into the two compensators, maybe 80% of 80% (are you following?) to main, and 20% to reserve. Once reserve compen had reached our target value, transfer the whole lot to main comp (which then shoots up to level 6 - super generous!) and get rid of it. Maybe set a flag to say "big win time" and force a red mode or jackpot repeater.
Believe it or not, often, the more simple the game (lo-tech/Bar-X) the more compensators there were. From memory, some of our lo-techs had 20+ compensators, all receiving a small % of the stake each game, and then use to pay for things happening in the game (multiple streaks, hopper-emptying wins, etc).
Hope that's useful to some - let me know of any questions!
What would you like to know about next?
