Unveiling The Complexity Behind RNG Programming In Online Slot Games

Ever wondered how an app comes up with random numbers? While we’re used to seeing various different libraries and modules that seem to pluck a random number from thin air, there’s a little more to it than that. Even if you’re not a computer programmer, and just a casino player enjoying a collection of no deposit free spins, it’s interesting to know how online slots work.

In this piece, we’ll walk you through the basics of Random Number Generators (RNGs) in online slot games to give you an idea of how you could potentially make your own.

Slots game development

Before we dive into RNGs used in slot games, we need to take a look at the mechanics and rules behind online slot games themselves. Like other casino games, slot games involve both chance and probabilities to calculate a result.

In a game of poker, you can calculate the probability of winning a hand based on the number of cards, cards on the table, and players in the game, along with the cards currently in your hand. When a new card is dealt it involves an element of chance, and you can calculate your rough odds of getting a desirable card from the dealer – and whether it could possibly help other players too. In setting up a game like this, the computer would need to randomize the next card dealt from the cards remaining.

In slot games, the chance element comes from which symbol will land on each slot reel. All slot reels in a game are independent of each other, so each reel will need a new randomizer. Remember this point for later. Let’s say there are five reels, of lengths 43, 73, 77, 73, and 43. These will be arrays of symbols in the code. For each spin, each reel will need to choose a number between zero and the max slot length, or one and the max slot length plus one, depending on how arrays are handled.

For demonstration purposes, let’s say that there is one Wild on each reel. That will mean the chance of getting five wild symbols will be 1 in (43 x 73 x 77 x 73 x 43) = 1 in 758,705,717. Thankfully, there is usually more than one type of symbol on each reel. The bad news? You don’t know the layout of the reels, so you can’t calculate that probability yourself – unless you’re on the other side of the fence creating the game.

Slots game rules of operation

To become a legitimate online slot operator, companies need to comply with the rules and regulations provided by the licensing body that gives the company their license and that audits the company for compliance.

One of the rules of operating an online casino is that they must ensure their odds are both correct and are calculated correctly, leading to random results within the bounds of play. This may be tested during the initial licensing period of the casino, as well as during any audits required for keeping up the license.

RNGs in slots

Random number generators, if you remember your computer science basics, aren’t always random. If you enter the same seed in a given random number, you will get the same sequence of results. This means that you need to set the seed by sampling from something external to the application with random input, such as /dev/random. The system clock is also popular for seed generation.

RNGs in most standard libraries are based on the Mersenne Twister random number generator. Online slot operators may or may not use RNGs from standard libraries. It is often easier for them to use these standard libraries, as it makes auditing from the licensing authorities easier and thus saves them time.

There is also the concept of provably fair casinos, where players can verify the results of the random numbers generated by checking on the blockchain post-game with the seed generator. This can help players feel more at ease instead of having no concept of whether an RNG is even being used in play.

It is highly unlikely that any online casino would use its own privately programmed random number generator for slot machine development. This would make complying with the terms of their licensing conditions very difficult as the process would be significant for the auditors to comb through the code to check for correctness.

Try it yourself!

Developing a basic slot machine game in C# isn’t too tricky now that you know the basics. Using Random() as your RNG, you will be able to create something new that works as expected in no time flat. Go ahead and try it out yourself!