The PS4 racer’s principal programmer details the game’s custom physics engine and competitive play ahead of this winter’s launch
Hi everyone, my name is Rob Baker and I’m the principal programmer on GRIP: Combat Racing, which means I’m responsible for producing all of the code for the game.
After starting work on the game back in 2014 we’re really excited to share today, after all this time, that GRIP will be released on PlayStation 4 on 6th November.
It’s been a painstaking development with difficult problems to solve. Making a game that pits vehicles against each other at over 700mph is a challenge even with cars that keep their wheels firmly on the road… but in GRIP you can drive on walls, ceilings or anything else you can get your tyres to.
Here’s three of the biggest challenges we’ve faced and how we’ve look to overcome them!
1. Dramatic downforce
Downforce in GRIP is a huge factor and is used to make the game’s signature gameplay a reality. All of the physics used to move the vehicles in game is custom-code written by us for the game itself.
At the speeds we’re dealing with, a realistic vehicle simply wouldn’t be drivable so we’ve had to do a huge amount of work to create a fun, playable game while still keeping it a believable and engaging driving experience.
Your downforce or GRIP in game is related to speed but disregards the shape and aerodynamics of the vehicle. One thing we learnt very early is that predictable handling was really important, so we’ve tried to as far as possible disregard aerodynamics in favour of better vehicle handling.
This simple calculation is then scaled even further by the vehicle’s orientation to walls or ceilings, with ceilings providing the most grip – enough to overcome gravity.
It was important not to use too much downforce all of the time, and rather the right amount at the right moment, because the more the suspension springs are compressed the more unwieldy the vehicle handling becomes.
2. Balancing competitive gameplay
We’ve put a lot of time into balancing the gameplay in GRIP, having worked on several combat racers in years gone by, including Rollcage (a title from which GRIP draws inspiration), I’m all too familiar with getting hit and left behind on the start line.
GRIP has within the game 9 power-ups, each of which has been carefully considered and balanced to be devastating but not race ending, from exploding darts to Hydra missile systems the game offers great variety and even the ability for savvy racers to super-charge their arsenal and deliver a race changing blow.
On top of the weapons system, the three vehicle classes have been carefully balanced and we’ve implemented a system we call catch-up assist. This is a configurable race option which goes beyond just rubber banding the AI, catch-up assist subtly changes the forces on the vehicles based on position, helping to keep the racing pack tight for maximum carnage.
If you’re a fan of the purely balanced experience this can be switched off (and even used to filter for online games) but for us this gets left on for maximum fun.
3. Working as a satellite studio
Working as a satellite studio with individual team members based right around the world has definitely made for an interesting game development, with level designers, programmers, artists and other project team members spread right around the world we’ve had to work hard to bring the team together and even harder to keep development running smoothly.
I myself, am based in remote Indonesia, on a small island just off the most northerly tip of Sulawesi. Working off local power generators and almost entirely over a 4G phone connection with the waves lashing in around us… we’ve seen practically everything including island-wide power cuts, intense tropical thunderstorms, nearby volcanic eruptions and even the odd earth tremor – but we’ve always kept focussed. Nothing was stopping us getting this game out.
The game has been created in Unreal Engine 4, a massive departure from native programming for the original PlayStation this alongside PhysX has enabled us to create what we hope you’ll agree is a stunning game, taking full advantage of the PS4 and PS4 Pro.
We’re entering the final stages of development but we’re pleased to confirm that the game will support HDR on both platforms along with a number of other optimisations for PS4 Pro – with a target of 60fps gameplay for launch.