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How to Program Slot Machines

In any casino around the world, whether online or offline, slot machines are by far the most popular of all the games in the collection. It is not difficult to see why slots are a perennial favourite – they are simple to play, come in a huge variety of formats and themes, and have a relatively generous payout percentage.

Gaming software studios big and small publish hundreds of new slots each year, so players always have a great selection of brand new online slots to try out. Speaking of which, you can read this authoritative guide if you want to find out more about the latest slots. Most commercial games originate from these professional settings, but slots can be developed and programmed by skilled amateurs as well.

If you are looking into game design either as a hobby or a profession, then slots could be a good place to start. Although the permutations are endless, the basic design varies very little. In this article we will look at some of the things you need to know about the creation of digital slot games. 

Slot Features and Function

A simple online slot game has three spinning reels and three horizontal paylines. It can get much more sophisticated than this, as any slot player knows, but it is probably best to start with a basic format and work up. Designing and building a slot game is a great project to test drive any newfound programming skills.

Professionally designed slots, whether simple or more complex, all have some common features. From the perspective of the player, the first thing to notice will be the theme and graphic design. If the hope is that your game will eventually be a marketable product, some though needs to go into this part of the process. Popular themes include mythology and gods, Ancient Egypt, horror, sci-fi and fantasy. A good tip is to find a unique spin on a popular theme, so that your game will attract players and stand out from the crowd. 

Digital slot games are both random and pre-programmed. Although this may seem like a paradox, it is easy to explain. Built into the programming there are certain parameters, and over time the outcome of the game will follow this. The two primary factors that are encoded in any slot game are volatility and return to player (RTP) percentage.

Volatility refers to the size and frequency of payouts. High volatility slots pay out larger amounts less often, while low volatility games have smaller and more consistent wins. The RTP is the percentage of money spent that a player can expect to get back, given a long enough time frame. A typical RTP of 96.5% will return $9.65 for every $10 spent. Some players will be lucky enough to hit a jackpot and make a profit, but on average and across all players, the house will pocket that three and a half cents on every dollar. 

The random aspect is created by the random number generator (RNG) which simulates real life conditions of chance. In actual fact, the RNG is not quite as random as true life, but it is so close as to make no practical difference. The RNG is responsible for ensuring that the outcome of each individual spin is entirely unpredictable and unrelated to the previous or the next. 

Making Slot Games from Scratch

There are a couple of different approaches that can be taken, depending on why you want to make a slot game. If you have what you believe to be a unique and marketable idea for a slot game, but lack the technical skills, you may wish to go with an off-the-shelf solution. There are companies that provide an entire template for a digital slot game, and they take care of the more complex aspects of the development. This is of course the costliest way to make a slot, but if you can sell the final product and it is a success, then you are sure to profit.

A less high-risk strategy is to use software or apps that have been created specifically for making slots. The great thing about these is that they don’t require a high degree of technical proficiency to master. Anyone with some time, patience and a little imagination can make a slot. The limiting factor is that you will not have completely free reign over the design and functionality. 

Finally, we come to building a slot game from the ground up. This of course requires knowledge of coding and at least one coding language. The good news is that there are several well-known languages that are eminently suitable for this type of game design. So, if you already know one then chances are you will not need to learn another for the sole purpose of making a slot. 

Some of the better languages for the task are Java, C, C++ and Python. Any one of these will do very well, and even less experienced programmers are sure to know one or more. Of course, if you are building a slot for the very first time then it is more likely to be a project for learning than for selling and profit.

If this is the case, then there are a lot of resources to be found online. Many coders have made step-by-step video tutorials to help anyone get started with the basics. It is possible to create a rudimentary three-reel slot game in under half an hour. Once you have got to grips with the fundamentals, then you can slowly add more and more complexity, learning as you go.