How does PS4 Pro improve the PlayStation VR experience?
Digital Foundry puts a number of Pro-enabled virtual reality titles to the test.
Some might say that the new PlayStation 4 Pro is better equipped for enhanced VR gaming as opposed to its stated purpose of adapting titles for ultra HD displays. Effectively doubling GPU power over base hardware opens up a range of options for improving PlayStation VR titles - an area where smooth frame-rates take priority over image quality or graphical features on standard PS4 hardware. So the question is simple: to what extent does PSVR benefit with a PS4 Pro upgrade?
Of course, we need to bear in mind that it's early days for PS4 Pro development in general, as evidenced by a small number of sub-optimal ports we've seen so far. On top of that, there are commercial considerations to take into account. Development budgets for VR will be constrained enough already, owing to the relatively limited number of launch units out in the wild. To add support for this specific combination of PS4 Pro and PSVR - a subset of an already small installed base - is perhaps a hard sell for a developer when it comes to allocating development resources.
This may explain comments from DriveClub VR's developer, hinting that only a few visual features are enabled in PSVR's flagship racer on PlayStation 4 Pro. As it happens, we struggled to find any at all, though further comparisons revealed enhanced reflections are enabled on the body work of the car. Otherwise, the rest of our comparisons came up empty. Admittedly, we are hamstrung here; the social feed limits resolution, making pixel-count comparisons difficult. And even access to the HMD feed offers limited results owing to the distortion pass added to account for PSVR's lenses. Truly, there is nothing quite like actually putting on the headset to judge the actual differences - something we can't really present in an article, or even a video.
Nevertheless, there are clear enhancements to the experience offered by PS4 Pro on select titles. Take Crytek's Robinson: The Journey, for example. Most games use the Pro's extra processing power to simply render at a higher resolution, and this title is one of the best examples of this. While you're always viewing the headset's pixels up-close, at least by rendering games at higher resolutions, PS4 Pro can super-sample the frame for better anti-aliasing. It offers less shimmer, less visual noise, and a cleaner, more pristine image all round. Robinson visibly benefits with the headset on, and this reflects the number one advantage across a breadth of VR titles we've tried on PS4 Pro.
In particular, you can see the gains in Robinson to the corners of the screen. The so-called 'foveated rendering' technique, used to cull peripheral resolution to save on performance, isn't as aggressive implemented on PS4 Pro. There's still a blurring to the display's edges, but details are clearly much crisper compared to the standard PS4 delivery. Additionally, Crytek outlines several visual enhancements beyond a resolution bump, including improved screen-space directional occlusion, and ambient occlusion - allowing better shading between objects.
In practise, this proves too slight to pick out in play, but an improvement in texture filtering is at least clear to see across the ground. With the headset on, the blur across surfaces is massively reduced. Textures remain identical on both base PS4 and PS4 Pro, and likewise for shadow and object quality - but the boost for texture filtering is hugely welcome for any long distance views. Enhanced draw distance is also evident, again working well in concert with the other enhancements.
Robinson possibly offers up a 'best case scenario' for PSVR improvements on Pro in the here and now - CryEngine has a huge toolbox of potential improvements already built into the engine, and as a PSVR exclusive, it may have also received additional funding that helps make the business case. But it's clear that the concept of increased resolution for super-sampling, alongside a small handful of extra visual features, is a template for the other games we've tested.
Take Rebellion's Battlezone, for example. This is a very straightforward case, and the benefits of playing in VR with PS4 Pro are again focused on image quality. Much like Robinson you get increased resolution, super-sampled to the 960x1080 view on each eye within the PSVR headset, resulting in a marked jump in clarity with PS4 Pro. On top of that, dynamic lighting inside the cockpit is improved - it's only active in cut-scenes on base PS4, but enabled throughout the game on Pro. It means HUD details and external factors (radar blips, explosions) adjust in-cockpit lighting too. Performance remains just as solid.
It's a similar story for Guerrilla Cambridge's Rigs. Here we have another game where the lower resolution and high contrast artwork shows obvious scaling artefacts on base PlayStation 4 hardware. With PS4 Pro, you get a vast improvement in image quality with the headset on, and again, peripheral detail is much improved with the dialing back of foveating rendering. There is no game-changing improvement offered by the Pro, but the enhanced resolution clearly helps in mitigating the most striking of PSVR's visual compromises.
We've also played pre-release builds of Farpoint, a first-person shooter for PSVR. The base PS4 version had clear frame-rate issues (something we expect to see cleaned up for launch) while the utilisation of high contrast artwork produced obvious stair-step artefacts. The PlayStation 4 Pro code, shown at the PlayStation Meeting in September was silky smooth by comparison and aliasing was far less of an issue - perhaps not surprising, bearing in mind that the game apparently renders "twice as many pixels".
Overall, the pattern established so far suggests that in common with standard games, PS4 Pro enhances virtual reality mostly with a boost in resolution. It helps address a fundamental issue with many PSVR titles, but we can't help but wish for more. And in this case, Crytek's Robinson: The Journey perhaps offers up a look at how the Pro can be more fully utilised in providing a more complete package of enhancements. While it clearly requires more developer effort, we should consider that many VR titles are multi-platform in nature, built using middleware designed to support multiple targets.
It's entirely plausible that developers will dip into the middleware features not only improve resolution, but also to bring over visual enhancements previously reserved for the PC versions of their games. Robinson's improvements - pushed out LODs, improved ambient occlusion and higher levels of texture filtering - could prove to be the tip of the iceberg once developers have more time getting to grips with Sony's new console hardware.