In Inside XR Design we look at particular examples of nice VR design. Right now we’re wanting on the particulars of Half-Life: Alyx and the way they add an immersive layer to the sport hardly ever discovered elsewhere.
Editor’s Word: Half-Life: Alyx has been hailed by many not simply because the ‘greatest VR sport’, or ‘greatest Half-Life‘ sport, however even one of many ‘greatest video games ever’. 5 years after its launch, the sport holds the twenty fourth spot on Steam250’s checklist of one of the best rated video games on all of Steam. In celebration of the sport’s fifth anniversary, we’re republishing our Inside XR Design episode which explores the main points which have cemented it as one in every of VR’s seminal titles.
Yow will discover the whole video beneath, or proceed studying for an tailored textual content model.
Intro
Now pay attention, I do know you’ve virtually actually heard of Half-Life: Alyx (2020), it’s top-of-the-line VR video games made up to now. And there’s tons of the reason why it’s so properly regarded. It’s received nice graphics, enjoyable puzzles, memorable set-pieces, an attention-grabbing story… and on and on. Everyone knows this already.
However the scope of Alyx permits the sport to go above and past what we often see in VR with some superior immersive particulars that basically make it shine. Right now I need to look at a bunch of these little particulars—and even if you happen to’re an absolute grasp of the sport, I hope you’ll discover at the least one factor you didn’t already find out about.
Inertia Physics
First is the actually good method that Alyx handles inertia physics. Numerous VR video games use inertia to offer gamers the sensation that objects have completely different weights. This makes transferring a small and light-weight object really feel completely completely different than a big and heavy object, however it often comes with a sacrifice which is making bigger objects far more difficult to throw as a result of the participant has to account for the inertia sway as they throw the thing.
Alyx makes a tiny little tweak to this components by ignoring the inertia sway solely in its throwing calculation. Meaning if you happen to’re attempting to precisely throw a big object, you possibly can simply swing your arm and launch in a method that feels pure and also you’ll get an correct throw even if you happen to didn’t contemplate the thing’s inertia.
This offers the sport one of the best of each worlds—an inertia system to convey weight however with out sacrificing the usability of throwing.
I like this sort of consideration to element as a result of it makes the expertise higher with out gamers realizing something is going on.
Sound Design
Word: Be certain to unmute clips on this part
Relating to sound design, Alyx is basically up there not simply by way of high quality, however intimately too. Considered one of my absolute favourite particulars on this sport is that just about each object has a unique sound when being shaken. And this reads particularly properly as a result of it’s spatial audio, so that you’ll hear it most from the ear that’s closest to the shaken object:
That is one thing that no flatscreen sport wants as a result of solely in VR do gamers have the flexibility to choose up virtually something within the sport.
I can simply think about the sound design workforce wanting on the sport’s in depth checklist of props and realizing they should give you what a VHS tape or a… TV appears like when shaken.
That’s a ton of labor for this little element that most individuals received’t discover, however it actually helps hold gamers immersed after they decide up, say, a field of matches and listen to the precise sound they’d count on to listen to in the event that they shook it in actual life.
Gravity Gloves In-depth
Okay so everybody is aware of the Gravity Gloves in Alyx are a diegetic option to give gamers a pressure pull functionality so it’s simpler to seize objects at a distance. And virtually everybody I’ve talked to agrees they work exceptionally properly. They’re not solely useful, however enjoyable and satisfying to make use of.
However what precisely makes the gravity gloves maybe the one greatest force-pull implementation seen in VR up to now? Let’s break it down.
In most VR video games, force-pull mechanics have two levels:
- The primary, which we’ll name ‘choice’, is pointing at an object and seeing it highlighted.
- The second, which we’ll name ‘affirmation’, is urgent the seize button which pulls the thing to your hand.
Half-Life: Alyx provides a third stage to this components which is the important thing to why it really works so properly:
- First is ‘choice’, the place the thing glows so you realize what’s being focused.
- The second—let’s name it lock-on’—entails pulling the set off to substantiate your choice. When you do, the choice is locked-on; even if you happen to transfer your hand now the choice received’t change to every other object.
- The ultimate stage, ‘affirmation’, requires not a button press however a pulling gesture to lastly provoke the pressure pull.
Including that additional lock-on stage to the method considerably improves reliability as a result of it ensures that each the participant and the sport are on the identical web page earlier than the thing is pulled.
And it must be famous that every of those levels has distinct sounds which make it even clearer to the participant what’s being chosen in order that they know that every part goes in keeping with their intentions.
The usage of a pulling gesture makes the entire thing extra immersive by making it really feel like the sport world is responding to your bodily actions, quite than the press of a button.
There’s additionally just a little little bit of magic to the precise pace and trajectory the objects observe, like how the trajectory can shift in real-time to succeed in the participant’s hand. These parameters are rigorously tuned to really feel satisfying with out feeling like the thing simply routinely attaches to your hand each time.
This strikes me as one thing that an animator might even have weighed in on to say, “how will we get that to really feel simply proper?”
Working Wearables
It’s pure for gamers in VR to attempt to put a hat on their head after they discover one, however do you know that sporting a hat protects you from barnacles? And sure, that’s the official title for these horrible creatures that stick with the ceiling.
Nevertheless it’s not simply hats you possibly can put on. The sport is surprisingly good about letting gamers put on something that’s even vaguely hat-shaped. Like cones and even pots.
I determine that is one thing that Valve added after watching quite a lot of playtesters try and put on these objects on their head throughout growth.
Talking of sporting props, you may as well put on fuel masks. And the sport takes this one step additional… the fuel masks really work. One a part of the sport requires you to carry your hand as much as cowl you mouth to keep away from respiration spores which make you cough and provides away your place.
If you happen to put on a fuel masks you might be equally protected, however you additionally get using each palms which provides the fuel masks a bonus over masking your mouth together with your hand.
The sport by no means explicitly tells you that the fuel masks can even shield you from the spores, it simply lets gamers determine it out on their very own—form of like a practical easter egg.
Spectator View
Subsequent up is a function that’s straightforward to neglect about until you’ve spent numerous time watching different folks play Half-Life: Alyx… the sport has an optionally available spectator interface which reveals up solely on the pc monitor. The interface provides viewers the very same info that the precise participant has whereas within the sport: like, which weapons they’ve unlocked or outfitted and the way a lot well being and resin they’ve. The interface even reveals what gadgets are stowed within the participant’s ‘hand-pockets’.
And Valve went additional than simply including an interface for spectators, in addition they added built-in digicam smoothing, zoom ranges, and even a selector to choose which eye the digicam will look by means of.
The final one may look like a minor element, however as a result of persons are both left or right-eye dominant, having the ability to select your dominant eye means the spectator will accurately see what you’re aiming at while you’re aiming down the scope of a gun.
Multi-modal Menu
Whereas we’re wanting on the menus right here, it’s additionally value noting that the sport menu is primarily designed for laser pointer interplay, however it additionally works like a touchscreen.
Whereas this appears perhaps trivial at present, let’s do not forget that Alyx was launched virtually 4 years in the past(!). The foresight to supply each modalities implies that irrespective of if the participant’s first intuition is to the touch the menu or use the laser, each decisions are equally right.
Guiding Your Eye
All key gadgets in Alyx have delicate lights on them to attract your consideration. That is fundamental sport design stuff, however I’ve to say that Alyx’s method is way much less immersion breaking than many VR video games the place key objects are highlighted in a manifestly apparent yellow mesh.
For the pistol journal, the sport makes it clear even at a distance what number of bullets are within the journal… in truth, it does this in two alternative ways.
First, each bullet has a small gentle on it which helps you to see from the aspect of the journal roughly how full it’s.
After which on the underside of the journal there’s a radial indicator that depletes because the ammo runs down.
As a result of that is all executed with gentle, if the journal is half full, it is going to be half as vibrant—making it straightforward for gamers to inform simply how ‘invaluable’ the journal is with only a look, even at a distance. Fully empty magazines emit no gentle so that you don’t mistake them for one thing helpful. Many gamers be taught this affordance shortly, even with out considering a lot about it.
The takeaway right here is {that a} sport’s mostly used gadgets—the issues gamers will work together with essentially the most—must be the issues which can be most thoughtfully designed. Gamers will gather and reload actually lots of of magazines all through the sport, so spending time so as to add these delicate particulars meaningfully improves the whole expertise.
