PHYSICS

PGA TOUR 2K23 is driven by physics, making it the undisputed leader in ultra-realistic gameplay. Dating back to The Golf Club, HB Studios has always put responsive feedback and life-like physics at the forefront of their games. In PGA TOUR 2K23, real world data from the Beaufort scale is used to create wind simulations in-game and run thousands of simulator tests to refine gradient possibilities, among other things. Recently, the HB Studios design team pulled back the curtain to reveal how they deliver such authentic results.

Q: PGA TOUR 2K23 offers unrivaled realism thanks to its refined physics. How did the team approach designing and fine tuning the algorithm in its early stages?

Everything in our game is physics driven. All the familiar data from your favorite launch monitors gets pumped into our simulation. The club head properties, head speed, clubface angle, attack angle, dynamic loft, spin loft, swing path, etc. are all taken into account when generating the initial launch properties of the ball such as spin rate, spin axis, velocity, launch angle/direction. After making contact, you are at the mercy of our ball flight physics and then ultimately our bounce and run physics. During flight, your ball is mainly affected by drag, and the magnus effect. For drag and the magnus effect, we took great pains to get this right researching and implementing the complex interaction between the properties of the golf ball, the spin rate, velocity, and the atmospheric conditions.

For the bounce and run physics we had to write our own custom collision/response system to simulate collisions with deformable terrain such as the different types of surfaces you find on a golf course. We run tens of thousands of simulations in our proprietary physics simulator, the Proving Grounds, using the results of those simulations to refine the extremes and all the gradient possibilities in between for how a ball will interact with a given surface given the impact angle, impact velocity, impact spin, grass density, etc.

We pored over mountains of physics papers and studies and scoured endless video references for all aspects of the game of golf throughout the development of this franchise to ensure we are putting out the best physics simulation we possibly can. As new papers and data surface we have the tools to tune and refine our simulation.

Q: Can you touch on how you were able to tweak the ball behavior for each shot type?

This all stems back to our Club-to-Ball interaction at the point of contact. As our Proving Grounds continue to grow so too will the accuracy of our simulation. We spend countless hours and countless more simulation cycles testing, tweaking, and tuning every club, every shot type, and every surface type combination. Using the Pro Data we have available to us, we’re able to recreate launch parameters on a club by club, shot by shot basis.

Q: How have the physics been upgraded from PGA TOUR 2K21? Was there an emphasis placed on improving any areas in particular?

Clubs and ball interaction at contact was at the forefront of our focus. All of the simulation inputs mentioned above have been meticulously tuned to give each shot type its unique behavior. In reality these are simply presets to the thousands of shot type variants you can achieve using our True Shot Shaper which allows the player to create the perfect shot for any situation they might find themselves in. This year the shot types have been refined to inputs that align with PGA TOUR pros.

Q: How does physics change from course to course?

Every surface type that we offer, from fairway to green, from bunker to heavy rough, from cart path to pine straw, all have their own unique physics properties. Those physics properties are tuned at the extremes, put through the paces, and then refined at every gradient in between. What this means from course to course is that both we and our community of players, who are using the Course Designer to create the course of their dreams, can fine tune the behaviors of each of the surfaces out on the course. These powerful tools allow each course created in the course designer to play differently. These are the very same tools that our internal team uses to create our official courses.

Q: How do you compute the effect of wind and weather on ball physics?

Our wind simulation is based on empirical real word data and its behavior at different wind speeds using the Beaufort scale. Its effect on the golf ball is the closest representation in any golf game to date. It can blow up a high-spinning shot when hitting into a head wind or get you that extra carry in a tailwind. Quarter crosswinds are where things get really interesting. Beware the quarter crosswind.

Q: How have improvements in technology made producing responsive and accurate results more achievable in PGA TOUR 2K?

It’s been challenging actually. We’ve been pushing for input parity across input devices since the early days of The Golf Club, and with each new advancement comes new hurdles. As platforms aim to differentiate themselves from one another, we’ve been trying to pull them back in to behave as equally as possible. Our input system strives to produce the most nuanced of differences from shot to shot, especially at our most competitive difficulty levels. Those nuances can feel different between input devices if left unchecked, so we've put a lot of effort into bringing each in line with the other.

Q: What was it like matching each pro’s swing in real life to the game?

From a motion capture and animation standpoint the best way to match the pros’ gameplay swings as closely to their real life swings is to get them suited up and onto the motion capture stage. We do our best to prioritize those shoots to ensure we’re capturing the most common swings first, moving on to the lesser seen swing types and then of course adding additional personal flair captures wherever we can fit them in (i.e. idles, walk cycles, reactions). The next step is to process it onto the respective in-game characters and take each motion through a clean-up and polish pass from the animation team. Once the animation team has the digital version of the swings looking good, they are then integrated into the game and tuned to work with our controls.

A short summary like this can make the process sound fairly straight forward but it certainly has its challenges and a lot of hard work goes into it. We’ve been very pleased with the results overall and adding this extra bit of authenticity goes a long way to properly representing these high-caliber athletes and the intricacies in their movements that make them unique.

Q: Are there any small details to the physics that you'd love players to know about?

There’s actually a lot of minute physics interactions between the ball and surfaces that can be hard to appreciate. Like, how the ball jostles and hops about as it runs out through the grass, or grinds to a stop as it hits the thick stuff. How that same heavy rough can bury a ball and also have it sitting up. Or how the ball reacts as it transitions from surface to surface. These aren’t really considered “features” to us. They are simply requirements when simulating the game of golf.

Additionally, our True Shot Shaper can sometimes be overlooked. This system allows so much creativity and freedom for our players to create any shot imaginable through our physics based swing system. There’s a bit of a learning curve there, as there is with golf in general, but once you start using it you can really change how you approach each and every shot.

For years, HB Studios has perfected the art of in-game ball and weather physics using real-world data to create the authentic gameplay experience. No unnecessary frills and no gimmicks, just tried and true results. Each course presents unique challenges that’ll force you to think critically and creatively about how to best utilize the clubs in your bag. Whether you’re shot-shaping, hitting a splash shot out of the bunker, or pitching it from 45 yards out, each shot, roll, and bounce will respond in a lifelike, realistic manner.