Sometimes, it’s difficult to put your finger on why and how virtual reality (VR) gaming differs to traditional gaming. Of course, there’s the obvious immersion point – in VR you’re actually in the game rather than viewing it – but what about gameplay mechanics? How do they really differ? The Elder Scrolls V: Skyrim VR and Fallout 4 VR are amazingly immersive in VR but, outside of being able to move your weapons in independent directions, is the core gameplay any different from their flatscreen incarnations?

A growing trend in the VR scene has been the rise of titles that attempt to utilise realistic physics-driven interaction systems as core gameplay mechanics. This trend began with games like H3VR and Gorn and has gained momentum recently through titles such as Blade & Sorcery, Boneworks and The Walking Dead: Saints & Sinners. These videogames are based around employing consistent, universal and realistic physics rules to every object in an experience so that when a player manipulates or uses that object it reacts realistically (or at least consistently) to both the player’s input and all other objects and masses in the VR space. It feels very much like the next step on the evolutionary path of VR gaming and one that truly differentiates it from traditional gaming.

Adding weight and mass to thin air!

What does this mean in practice? In the titles mentioned above, not only can almost every item in their worlds be picked up, moved, thrown and manipulated but there is also an attempt to give each item weight and mass. Quite a difficult thing to pull off convincingly when in the real world the player is just pushing air particles around! When I pick up a huge axe in a videogame like Blade & Sorcery there is a realistic approximation of its weight. I can’t just pick up this axe with one hand and waggle it around weightlessly. It has realistic physics and it will droop uselessly if I use it with one hand, greatly diminishing its damage potential if I try to hit an enemy (as would be the case in real life). Rather, I need to pick it up with two hands and mime slow swings like it has actual weight. This sounds unintuitive but it’s anything but. It’s actually a lot of fun and surprisingly effective at making you believe you’re swinging around a hulking great piece of metal. Furthermore, if I swing the axe at a wall it will bounce off it rather than just glide through. If I hit a pot it will smash. If I crunch it into a competitor gladiator’s arm it will (gruesomely) dismember them!

Realistic, advanced physics take VR immersion and gameplay to the next level

When we talk about realistic physics simulation this is what we mean. While it might not seem like the most obvious selling point for VR – “realistic physics” doesn’t exactly scream must play – the benefits are immense. Firstly, it adds hugely to the overall immersion. Visually placing you in an environment is one thing in VR, but when you’re placed in a space and then each object you touch, grab or swing reacts as you expect, and has its own physicality and weight, it’s amazing how your brain can be tricked into believing that what is in front of you is somehow real and actually there. I spent a ridiculous amount of time in the first few areas of Boneworks simply overturning tables, pushing over filing cabinets and picking up and throwing computer screens. It’s just so much fun to simply exist and mess around in a VR space when you can grab and manipulate all the in-game objects around you.

Secondly, and very much in line with the trend we’ve seen in VR gaming during 2019 and early 2020, there are endlessly entertaining ways to incorporate realistic and consistent physics into gameplay mechanics that facilitate player creativity and expression. The most obvious example is through weapons. When your weapons and your enemies have weight and presence it’s remarkable how many ways to tackle combat situations present themselves. Suddenly, every cool move you’ve seen in a sword and shield or gun-based action film is there for you to emulate. A quick search on YouTube for Sword & Sorcery’s best kills will throw up all manner of complicated and convoluted (and, it has to be said, cool) melee combat sequences which show a whole range of sword, axe, knife and pike sequences that are equal parts shocking and thrilling in their brutality and creativity. On the less gruesome side, if that machine gun now has weight and presence in-game (as in Boneworks), not only can you use it to shoot an enemy (as you would in any videogame), but it can become a multi-purpose tool; one you can use to push open doors or hook over a ledge to use as a climbing aid or as a bar on a zip line.

There’s an almost endless amount of ways you can manipulate these believable in-game props to come up with creative and original ways to defeat enemies, overcome puzzles or navigate parts of the environment. This level of interactivity is just not possible in traditional 2D videogames. They are bound by input methods on a gamepad or keyboard and there’s only a limited number of possible combinations. When motion controls are coupled with in-game objects and weapons that have physicality, the combinations of possible manipulations and consequences are nearly endless and don’t have to be pre-programmed.

Advanced physics are more than just realistic gore

So far I’ve focused on combat but physics-based gameplay lends itself equally well to a whole multitude of titles. Gadgeteer is a great example of how consistent and realistic physics can enhance a VR puzzle videogame. Each lego-like piece that you use to create reaction contraptions (think Rube Goldberg machines) revolves around realistic physics and how one piece interacts with another. The fact that in VR all of these pieces can be touched, pushed, lifted and manipulated like you would in real life lends Gadgeteer an incredible tactility while also allowing various tracks to be flexibly laid out in full 3D spaces. Being able to pick up and handle each intricate piece like you would in the real world, while also seeing them react to other objects as you expect and anticipate, based on your inherent understanding of how real-world physics work, makes the game incredibly easy to pick up and play and in no time at all you’re able to create elaborate chain reaction machines that will surprise you with their scope.

The challenges of implementing realistic physics

So why don’t all VR games incorporate advanced physics simulations and why haven’t they since VR first appeared? Well, for one thing, these physics are difficult and complicated to bake into a videogame. It takes developers many, many hours of development time to understand how to implement these physics and to work through all the various permutations of how each object in a game reacts to another.

The second consideration when implementing realistic physics is how far to take them. Just because a VR title has astonishingly realistic physics doesn’t necessarily make it a fun videogame. Arguably, Boneworks has the best recreation of realistic physics we’ve yet seen but there are moments when it can be annoying from a design perspective. There have been numerous times when I’m running through a level only to find that my character’s foot is stuck on a pavement curb and so I can’t move. Likewise, my gun has often smashed into a corner as I try to round it quickly or a limb gets stuck in a large grating. This also points to another issue with implementing realistic physics in VR: ’jank’. All VR physics titles that I’ve played so far have janky moments and you’ll often see an object react strangely or an enemy contorted into bizarre positions or tripping over the smallest item. Glitches and bugs are part and parcel for implementing these complex systems but it can still be immersion breaking to see some of the ridiculous scenarios thrown up.

Will Half-Life: Alyx find the perfect balance?

So, there are clearly some steps that need to be taken to find the right balance between implementing realistic physics-driven gameplay while keeping a videogame fun, accessible and polished. We’ve already seen this happen to some extent with The Walking Dead Saints & Sinners, which provided a slightly watered down physics simulation when compared to Boneworks or Blade & Sorcery, but still made sure that key object iteration and combat had that immersive physicality and weight. More excitingly though, Half-Life: Alyx, which is only weeks away from launch, seems to elegantly combine detailed, realistic object interaction and physics simulations with immense polish and accessibility. If it nails that balance we really could be on the cusp of a VR gaming revolution – one heavily based around realistic physics that will provide unheard of levels of player interaction and will be hard for a mainstream gaming audience to resist.