Hey everyone !
My name is Pablo, and I’m the lead developer of our physics team for Motocross The Game. Today, as we wrap up the first week of our Kikckstarter campaign, I wanted to take some time to introduce you to our new physics engine that will power MTG, and more generally, to talk about our design philosophy, some of the features to expect from the game but also, to give you more perspective about our vision of what should be a competitive motocross game. But first, some background.
As you might have already guessed, the amazing team I’m working with on MTG has been put together especially to make this game. Coming from widely different backgrounds, with some of us well known on the modding scene, others like myself long term video game professionals and even a real life motocross world champion (hi Stefy), we were all brought together by the fact that we share a few common passions : racing, motorcycles and video games.
After years playing on the existing games (we look at you MX Bikes, MX Simulator, MESX …) and contributing each in our own way on making the motocross video game scene a better place, we’ve reached a conclusion. If we want to make a difference, and finally have the game we have all been dreaming of, we need to make our own. And that’s how MTG came to be. A project born from pure passion for riding, with the hope of making the best virtual motocross experience possible.
A project like this is ambitious, to say the least. And even more so because we tackle one of the few areas of video games sims that never had a convincing answer. Where cars, planes, and even rockets simulations all have amazing games that have been developed over the years, with physics accuracy defying some industry tools, motorcycles sims rarely had their shining moments. And there is a reason for that : motorcycle is hard.
There are two major aspects that differentiate a bike from a car. First it only has two wheels, which in the 3D world we live in makes it inherently unstable, so it has to rely on a carefully crafted geometry and precise rider input to stay upright, a feat that very few games manage to do accurately. And secondly, the rider is not a dead mass behind the wheel, but an active component that changes the direction of the bike by moving in different positions, shifting the center of gravity. In motocross, it is even trickier as you spend half of the time in the air where complicated things happen with the gyroscopic effect and the angular momentum that allows the rider to change its orientation (whips!). All of this makes bikes messy and sometimes unpredictable, and it's part of the reason we love them.
But this complexity in the real world makes it very difficult to accurately represent the physics involved in the motion of a motorcycle, especially in off-road disciplines. This added to the general instability of the machine is what drives most game studios to go on the arcade side of physics. And who could blame them? It allows for a more predictable and shorter development while making sure that they release an easy to play game for a wide audience.
This is the reason why there are very few games that fit in the “sim” category for motorcycles, whereas we can count dozens for cars. With MTG, we want to fill this void and bring the first realistic and competition oriented (more on that later) motocross sim to PC and consoles. Our goal is to make a game that has the same level of physics accuracy for motorcycles as an iRacing or Assetto Corsa would have for cars. No arcadish behavior, no scripting and no shortcuts when it comes to aerial gameplay as seen in many games : only cold hard physics moving the bike and rider.
For that, we’ve decided to go the long road, and start from scratch with our in-house physics engine tailor-made for motocross simulation. So, with all that said, what is to be expected from there? Well, without going into too much detail, we will do in time as the game development moves forward, here are some of the most important aspects of our physics simulation.
Industry Standard tire model
The tire is by far the most important component of a wheeled vehicle, it is from there that arises most of the forces that will be applied to the bike. Getting it right is one of the most experience-defining features of a sim, but also one of the most difficult to correctly tune.
To get a realistic behavior in our game, we use the Pacejka tire model, also called the “magic tire formula”, that is widely accepted as the best at managing tires reactions under varying loads, camber angles and slip conditions to the point that it is used in real life performance tire development. On top of that, we will include in-house code that takes into account the terrain deformation under the tire to properly model the friction of dirt tracks.
Complete bike geometry and full suspension simulation
Motorcycles have complicated systems that compose the front and rear suspension elements. The reason for that is that they have to accomplish both the task of damping the irregularities of the road and handle jump receptions, but also to make the steering stable and responsive with the correct trail and dynamic wheel base. Because we know how important they are, we will make sure to replicate them as precisely as possible without the simplifications made in many video games and based on real life data coming from our industry partners.
Accurate rider movement
The rider movement is a defining aspect of riding a motorcycle. Where in almost all other powered vehicles the pilot is strapped to his seat, on a motorcycle, the rider is an active part of the system and has to move its weight around in a variety of ways depending on the situation. In MTG we will model the moving mass of the rider relative to the bike so that it will have a direct influence on the weight distribution, the inertia and the reaction to external forces on the bikes.
Realistic engine
Having a proper engine simulation is paramount in a realistic racing game as it is the source of all motion of the bike. It is also responsible for a credible sound and accurate throttle control and engine braking. To make sure that our bikes behave as in real life, we will get all the power and torque curves, engine inertia and gearbox data right with factory data coming from manufacturers.
Wide range of tuning possibilities
A proper “sim” game is not all about having the best possible recreation of a real life vehicle, it is also a tool given to the players to better understand their favorite sport. And for that, we want to provide realistic tuning capabilities that mimic those of real life bikes. From shock compression and rebound clicks to tire pressure and gear ratios, you will be able to experiment with them, and find the setup that suits you the best.
Realistic multi axis aerodynamics
One of the often overlooked aspects of games when it comes to vehicle simulation is the aerodynamics. Where many games settle for a simple unidimensional drag that is the same in any direction, we will go the extra length to have a dynamic, multi-axis aerodynamic simulation where the orientation of the bike, the relative wind, the air density and the rider’s position are taken into account when calculating the aerodynamic forces.
Ready for online competition
Online gaming brings a lot of new difficulties that solo games are exempt from. With delays and instabilities in the servers connection comes a wide range of issues that can adversely impact the flow of a multiplayer race. While these concerns mainly fall into the hands of the network programmers, a particular attention will also be given on the physics side to smooth out the network disturbances and avoid as much as possible unjustified falls, exaggerated collisions and other disruptions.
As you can see, there is a lot that goes into a proper motorcycle simulation. In a format like this, I can only scratch the tip of the iceberg, but my hope is that you now have a better understanding of the hard work we are putting into making MTG the best game possible.
Moving forward, we will communicate more about the behind the scenes that goes into the development and spend more time discussing the specifics. In the meantime, if like us you want to see this untapped potential come to life, please participate to our kickstarter campaign if you haven’t already, and follow us on social media to give the game the little push it needs.
Thank you for reading.
Pablo.