HOW TO BUILD A MONSTER JAM™ TRUCK
MONSTER JAM™ SHOWDOWN DEV DIARY
Hey, Drivers! How’s it going? Is your hype for Monster Jam™ Showdown growing? We hope so because we’re about to dig deep into the development process: specifically, we want you to have a look at how a Monster Jam™ truck is built! We have summoned Federico Spada, Game Director, and Gianni Pacella, 3D Artist for this. We’ll let them drive you through this amazing in-depth explanation. Fasten your seat belt and get ready for an unforgettable ride!
Hi, guys! We’ve already dealt with the introduction, and we know you have much to say. So let’s cut to the chase: what is it like to build a Monster Jam™ Truck from scratch? Maybe they aren’t 1:1 scale beasts, but we’re sure they put up a fight in the game.
You can say that again. Let me mention one thing to start: the Monster Jam™ Trucks are the most complex vehicles we’ve ever built, and we achieved this thanks to our previous experience with all our other games. I’m sure you can guess why it’s so complicated.
[Gianni Pacella, 3D Artist]
Well… probably because of the chassis. It’s more exposed compared to other vehicles.
Half right. First, Monster Jam™ Trucks have thin fiberglass bodies that tend to break very easily, when not flying away completely. Then comes the chassis. As you said, it’s more exposed compared to other vehicles, and this means we had to recreate it very faithfully in all of its parts – something you don’t do with other vehicles because the bodies cover it almost entirely. The fact that the chassis is tube-shaped doesn’t help either, since it won’t hide the underlying pieces: suspensions, driveshaft, the engine itself… all needed to be modeled till the last bolt. Each one of these parts had to move accordingly with their constraints, rotations degrees, etc. Every piece had to be precisely built to let it all function rightly. The same goes for the pedals in the cab. Thanks to the photo mode feature in the game, it’s easy to look at every nook and cranny of the Monster Jam™ Trucks. That’s why we needed to do everything right.
To start, we made a prototype based on a project the Monster Jam™ team gave us. It was only the exoskeleton, though, without any mechanics or other parts. We added them by looking at tons of photos and watching video references of real Monster Jam™ Trucks in action. From there, we managed to build a functioning prototype for the rest of the team, who then started to work on it. After that, we had the chance to fly to the US and see those beasts personally: we attended Monster Jam™ World Finals in Nashville, TN. Thanks to the reference team and the right equipment, we brought back home the entire chassis photogrammetry, together with other videos and details that proved very useful. We adjusted the prototype accordingly, and then we added specifics we otherwise couldn’t know about. From there, the first high-poly was born.
[Gianni Pacella, 3D Artist]
Just to be clear to our readers, can you explain what a high-poly is and what you use it for?
Of course. The high-poly is an ultra-defined model with endless polygons. It’s the base from where we produce every other version (PS5, PS4, Xbox Series X|S, Xbox One, PC and Switch). Keep in mind that everything I’ve said until now is about the static side of the Monster Jam™ Truck. Then comes the rig, which is the process of creating a skeleton for a 3D model so it can move. Together with the tech team, we studied how the suspensions and the steering work – after all, we’re talking about a four-wheel-drive plus a four-wheel-steering vehicle. What you have on the front, you have on the back, too: it’s symmetrical in its parts. After all of that, we were ready with a rigged model for the physics team, who tuned it based on every physical input the Monster Jam™ Truck received. It’s not uncommon in this phase to adjust the model even further. For example, if the suspensions need more stroke, we need to work on the inner part of the stems; or maybe during the steering, we notice some interpenetrations we have to fix. Whatever the case, we go back to the model, fix it, rig it, and test it again. A cycle you may need to do a lot of times before finding the right way.
[Gianni Pacella, 3D Artist]
The most interesting thing about this project has been the level of teamwork between the vehicle artist, the tech, and the physics team. As Gianni said, it’s truly complex on the technical side, not only in building the Monster Jam™ Truck per se but also for the physics simulation. All of these parts are extremely connected to each other, so the teams were always in touch – like, daily. I’ve never seen these departments work so close to each other.
[Federico Spada, Game Director]
Yes, there was a briefing for every Monster Jam™ Truck, especially regarding the body; if the chassis has its difficulties, so does the body. Again, we watched tons of references and calculated an average for the parts that needed to break – of course, it’s not the same as in reality, but we stuck to it as close as possible. We had to decide how the body would break and in how many pieces. So when you see the model intact, it’s like a sole mesh, but in reality, it already has all of its rifts, each with its own physics. For every one of them, we studied which bent and which broke off to make the right differences. As you can imagine, the process for the chassis was just as hard. While we strove for realism in our other games, we took it a step further with this one. Monster Jam™ Trucks are not production cars that come from dealers in perfect shape; they are handcrafted vehicles, each made individually with unique characteristics. No Monster Jam™ Trucks are exactly the same, which is part of their beauty. When we got home from Nashville and adjusted our prototype, we made sure to put emphasis on the characteristics and general differences that make each Monster Jam™ Truck so unique.
[Gianni Pacella, 3D Artist]
That’s commendable. Can you give a few examples?
On Megalodon™, the fin is slightly bent; the part where it connects with the chassis is cut by hand, and this lets you see part of the polystyrene it’s made of. We worked hard to faithfully recreate all of these small details. I won’t ruin the surprises, though, and will let our players discover them. Speaking of chassis, I assume our fans want to know how many we have.
[Gianni Pacella, 3D Artist]
You guessed correctly. Fair to say they’re eager to know this information.
The one we made the photogrammetry of is the CRD, the one used by roughly 90% of Monster Jam™ Trucks. Then, we have a specific one for Grave Digger™, which is also a CRD but a bit different in the roll bar. Oh, and if you’re curious to know, the Monster Jam truck we had access to in Nashville was the Monster Jam™ Stunt Truck, which is also slightly different. That said, even if most of the vehicles use the CRD chassis, each has its quirks, which of course we recreated, too. There’s something more I would like to add on the chassis, but it would ruin the surprise, so again: players, just wait patiently, and you’ll discover everything we made for this game so that it would be the coolest game so far.
[Gianni Pacella, 3D Artist]
Let me jump in for a moment to add one thing. The difficulties behind this project were mostly about the chassis and the body, not only because of the model per se but also because of the animation and the physics. Furthermore, unlike other motorsports events where contact is not only discouraged but not allowed in the regulations, for Monster Jam™, contact is like the golden rule. Whether it is with the terrain, the containers, or other objects, contact is not only welcomed but is also often the only way to perform a lot of tricks. For us, this comes with many more variables to consider. As Gianni said, we have the Monster Jam™ Truck’s body with its invisible rifts but the final break is an ongoing process. If you crash into something, the parts won’t instantly break into thousands of pieces: it all depends on what you crash into and the force of impact. Maybe the first time the pieces will just tear off, but they won’t break or fly away until a second or maybe a third crash. Within a common pattern for all the Monster Jam™ Trucks, each body breaks in different ways depending on its specifics. Think about, for example, Sparkle Smash™: the teams had to think about how, when, and in how many pieces its horn or tail would have broken into.
[Federico Spada, Game Director]
There’s also a hierarchy between said pieces. We had to take into account what would have happened if some pieces had broken before others, and act accordingly. As we said, it’s a complicated process but we’re very happy with the result, and we hope our fans will be, too.
[Gianni Pacella, 3D Artist]
We’re sure they will. Now, let’s talk about the elephant in the room: the physics.
As we mentioned before, the Monster Jam™ Truck is the most complex physics simulation we have right now. The vehicle’s specifics – double steering, all-wheel drive, and so on – have far from trivial implications physics-wise. You need to make a realistic physics simulation but you can’t hop in a Monster Jam™ Truck and drive it to get that intel. You can ride a bike or a car, so you have a grasp of their physics even though they’re not the exact ones you put into a respective game; you can’t do the same with a Monster Jam™ Truck. They’re not like any other vehicles, and you don’t have a license to test drive them to find out. This means you can’t make a direct comparison between reality and gaming, so you have to rely on video references, drivers’ experience, and all of these tiny little pieces to give yourself an idea of how the driving model works. You start with a driving model as realistic as possible, but then you have to fine tune it to find a compromise between reality, gaming – especially if it’s arcade-like – and the player’s expectations.
Imagining what it’s like to drive a Monster Jam™ Truck is not an easy task. All of the approximations and all of the choices you make to let it be drivable have repercussions on the 3D model. Remember what we said before about all the parts working together and how if just one of them is out of place, then the model must be reworked? This is an iterative process: you need to try again and again to finally find the best balance.
Another important aspect is that the core of this game is racing. As you know, these vehicles are designed for racing on a Monster Jam™ Track. For the outdoors part of the game, we had to use our imaginations, along with research, to see if what we thought actually made sense. Because of this, we have two physics “subsets”: one for outdoors racing and one for the stadiums. They work slightly differently and let the player have different feelings depending on what they’re playing. For example, suspensions work differently in the stadiums compared to the circuits. When racing on a Monster Jam™ Track, the suspension and tries allow for some bounce, which is helpful when performing some tricks. When racing outdoors on circuits, though, there is less bounce; otherwise, at your first right-left, you would instantly flip over. We aimed to both be engaging and challenging in their own way.
[Federico Spada, Game Director]
How did you come to shift the way of driving from the more faithful one in the stadiums to the one outdoors?
Thanks to all the experience we gathered with our previous games, especially Gravel since it’s a four-wheel game. We also played all of the previous Monster Jam™ titles, studying them thoroughly to understand what had been made before and how we could improve it. This is our gameplay theory. We’re delivering our vision of how the Monster Jam™ Trucks should behave in an entertaining way for an arcade game. One important thing to note is that the Monster Jam™ Truck itself is the heart and soul of the game and was the basis for everything else. For example, there are meters, feet, miles, inches, whatever, and then there’s the Monster Jam™ Truck measurement unit. What distinguishes us from other Monster Jam™ titles, and our fans have already noticed it, is the sense of scale. When you see these beasts closely, you realize how enormous they are, but the environment in which they move doesn’t have to be equal. You need to find a compromise to let the Monster Jam™ Truck stand out; otherwise, you have the toy effect, where the environment around you makes the Monster Jam™ Trucks feel tiny. Since we put a lot of effort into realism in building the trucks, with the exception of some creativity liberties, we had to develop the rest accordingly. It’s the Monster Jam™ Truck that sets the rules, not the other way around.
How large should this road be? Well, at least two Monster Jam™ Trucks. That’s how it went.
[Federico Spada, Game Director]
We hope you enjoyed this deep dive into the building of our Monster Jam™ Trucks. We’re not done yet, so be sure to stay tuned and follow us on our social media to keep track of the news!
