God of War: In-depth technical Analysis
Screaming from the single player throne!
Kratos was not the only one in exile for the past few years, the Studio behind the Greek hurricane have been absent of late. With an entrance fitting of a God themselves, they have thrust themselves firmly back into the spotlight and public eye with a triumphant return to form.
With the guidance of Corey Barlog at the helm and the broad collection of talent within the studio from across the globe this is much more than just a technical showpiece for them and the hardware, Kratos is back but leave your expectations at the door.
Raising the bar
It has become almost an expectation now that Sony 1st Party studios are at the forefront of the technical, Audio & visual possibilities within modern games. An ensemble of studios, talent and teams from across the globe that regularly do battle, raising the bar, to our collective benefit. Santa Monica studios were amongst the very best on the Playstation 3 and left that generation, in my opinion, with 2 of the most technically and artistically impressive games shipped on that complex hardware, proving that it was not only Kratos doing battle against immense odds. They have been suspicious by their absence during the PS4 era, helping publish other titles and shipping a remaster we have yet to enjoy the fruits of their labour, until this week. From the moment the game starts the leap from one generation to another is obvious, the model of Kratos himself is front and centre on just how big a leap that really is. All the subtle improvements add up, higher quality textures, PBR based material shaders, greater and higher quality normal maps, higher polygon counts and denser models, muscle simulation, the accuracy and coverage of the lighting and subsequent reactions to all these elements leave you with an in-game model that exceeds anything prior, even in-game. What left the last generation as a high point, has already aged more than the lead himself.
Something equally present as the astounding details and fantastical world you are transported to during the game. From dense foliage that reacts to movement as you slam the poor fools sorry enough to cross you, to the expansive vista’s, light starved caves and all manner of dreamlike environments leaves you in no doubt this they have gotten as close to the concept artist's vision as possible. Volumetric lights are spared no reprieve to enhance many of these areas as is Volumetric fog, as it floats inside caves or across streams, light bounces colours and breaks through trees that juxtaposed a peaceful serenity against the harsher and more desolate moments. The beautiful sections can also fool you into a false sense of security, but they can allow you to admire the effort poured into them, scale is ever present with you able to admire and appreciate this all much better from this new, intimate and single shot camera. Each tree bark, weathered stone face or worn wooden floorboard looks to have been painted on your screen from a real location, polygon count has increased but they have used it wisely, not swamping them across objects, instead balancing that load and certainly being far more conservative (relatively) with the culling. Occasionally you can see points that show this and the head of Kratos is a good point, vertex edges can be seen if you really look hard enough, but hardly a concern.
Resolving the little things
With this generation straddling the lines of arguably the biggest demand in resolution increases we have seen, an understandable level of fear has emerged for base console players being left behind with these new mid-gen refreshes targeting those 4K resolutions, Santa Monica have managed to straddle that delicate line almost to perfection. The drastic texture hike, artistic effort and vast detail packed into the game throughout play had me scratching my head as to how they managed to make a game on the base PS4 look this good, move this smoothly and present one of the sharpest, artefact free and overall pleasing presentations the console has seen. Nothing is missed within the native 1920x1080 display of this “base” 1.8TF machine. The image quality is remarkable, a careful balance of mip-map bias, Depth of Field, textured layers, decal additions, normal maps and one incredible particle system had me wondering if they had somehow managed to super-sample the image, with a sharpening filter that reduces the smudging affect it can have. I think some level of EQAA has also been used to sharpen up the polygon count the engine shifts, something they also excelled at on the PS3. This meticulous attention to keeping high frequency details to a minimum combined with the Temporal Anti-Aliasing pass leaves a game that is a confident argument in favour of not being outdated just yet, in isolation you would never ask or expect more from your machine than what you get, fill-rate wise. The temporal solution is clearly one of the best so far, a method of using previous information and the current frames to improve the image stability whilst in motion. This is of course more of an issue if you are playing on a large 4K screen, signs will emerge of the non-native image, but for HD screen players doubt you will yearn for any more pixels than delivered here.
Staying with resolution for now the Pro offers up 2 distinct options that have become a stable-mate on 1st Party titles and some 3rd party ones. Performance mode delivers an identical image quality, effects setting and resolution as the base PS4, but the extra GPU headroom is put to good use here by ramping up the performance levels considerably, 100% at times, but not during battles or some of the more Spectacular sequences. You can check out my separate Performance video below and the stats that cover all 3 versions/modes that I have tested across a variety of sections to give you a collective view alongside my realtime frame-rate average. If you played and enjoyed both PS3 releases of God of War titles, this performs better than those on average. I must also add that the base PS4 version also looks and plays brilliantly, to the point where I played through the first 8 hours or so with no issues at all.
The second mode favour Resolution, takes the Extra GPU power and the intelligent Checkerboard rendering functions, assisted by the hardware based ID buffer of the Pro to present a final screen resolution of 3840x2160. As these methods differ from engine to engine and team to team, it is impossible to confirm just how and what the combined rendering methods are, but something along the lines of Horizon’s 1920x2160 would be a rough level of pixels rendered in "standard" fashion per frame (what ever that is?). These techniques require a temporal AA pass to work correctly as they accumulate previous buffer info with the news ones and combined with nearest neighbour or bilinear type contingency options as fall back cases, in the event of missing data or errors. These are tightly coupled together within the engine’s rendering method that you can switch between these options in real-time without the need to restart the game, something that Monster Hunter World or GT Sport for example cannot do, even though they also use a “similar” Checkerboard mode within their engine, which helps demonstrate how varied and divisive these options are, even if they can all be grouped into the same category of sparse or conservative rendering, that is a very, very high level over-view mind. The results speak for themselves, with a supersampled image on a 1080 screen by default, but the true benefit and gain from this mode is with a UHD display and is where the choice of the 2 modes becomes more of a question, but the best thing is that choice is your own.
High Dynamic Range
The sacrifice of the higher performance levels give-way to an image that is fitting for a Native 4K display, the higher native pixel rendering makes significant improvements to Object micro-details such as moss, smoother and less dithered shadow maps that look cleaner and have much less pop and noise in play. Along with extra detail resolved on object edges and the incredible particle system. The CB solution can occasionally present some noisy patterns, or portions of smoothed detail at times, I would suspect 99.9% would notice this no matter the distance or size of screen, this type of detailed analysis is likely the only points it would be noted. The outcome is an image quality more in keeping with the immense pixel requirements of these modern displays and is how the game is best enjoyed if you have the relevant screen. This also includes HDR that the game supports on both models, being another high point of the title. Largely this comes does to, again, the incredible art direction and lighting model the game adopts to give high contrast segments that work best on the wider gamut afforded within the 10-Bit colour space. With dark cavernous sections allowing you to pick out the crevices and crannies within, as battles unfold the bright effects system illuminates the battlefield, light bleeding in, high bloom and yet the dark sections are unaffected by this. Outdoor segments benefit equally, with strong bloom lighting, multiple light sources and high contrast shining through on your screen, resolving details that can be easily clipped within an SDR tone-mapped image, something you can read more about on my site back when I went into depth on HDR before it became another selling point of consoles. It comes as another bonus to the games remarkably confident art direction and technical proficiency used here.
The sound of the heavens
I want to mention the sound design and music that accompanies and underlines the title. Sound effects, mixing and its punch are as vital as the visuals, and like the action, it delivers the required impact…. From the incredible voice acting from the entire cast, witty dialogue, genuine humour and emotional sequences are all superbly delivered and acoustically handled with aplomb. Battles yells are heard, directional processing allows you to locate if you have a suitable system or headphones, occlusion and reverb in caves just emphasis the attention it has. The satisfying crunch as you rip an enemy in two or the thud and crackle from an ice strike, even though these are all well in the fantasy zone, it sounds as you would expect. The incredible soundtrack from Bear McCreary heightens your adrenaline, making your hands stand on end or drawing a tear from the most jaded gamer, full of moody and gothic vocals and orchestral mix of strings and drums a more fitting and grandiose theme could not have been imagined.
The 2 options that Pro players have can offer a significant shift in the games frame-time delivery and allow you the player to choose the best option dependent on your screen type and console. The PS4 is capped at 30fps or 33ms for each and every frame which is mirrored within the Pro’s Resolution mode, the GPU resource is pushing more pixels within that longer time-slice than the base model and hands in a respectable metric on that target, ever so slightly better than the base PS4 but certainly not enough that anyone would notice. Aside some stressful small seconds within the real-time cut-scenes that I cannot show due to spoilers, seeing a brief drops into the low 20’s. The remainder of heavy action and cinematics play out with no frame-time exceeding 49.9ms and a low of 27fps, the balance is very good with the cuts-cenes being the biggest load on the GPU as lighting, animation and post effects are boosted and as these small dips happen during these passive moments it does not affect gameplay at all, which keeps my frametime graph flat almost all the time. My real-time average frame-rate demonstrates just how consistent all versions are, delivering 29.99 or 30 on each until the final cut-scene of my test starts in the video above as is an great example of the way the game plays out on base and the Pro in the Resolution mode. A commendable profiling use of the extra hardware that almost mirrors the PS4 performance profile to a T, leaving you with a nigh on locked 30Hz game across the wide spread of action, emotion and adventure the title offers.
Pro = Performance
The last mode, performance, is likely the one many Pro owners are most interested in, making far more sense on a 1080P display, this trades pixels for performance and now removes that 33ms fresh cycle maximum to a 16ms one, enabling the machine to push on-wards to that 60fps line. As players of previous God Of war games will already know, unlocked frame-rate are not knew for the Angry man from Athens, but the pleasant surprise is this new title and machine delivers a more commendable attempt at that figure than the previous PS3 releases. Across the same sections as you see here with all 3 versions, the reduction in output clarity is minimal, dependant on your screen, when compared to the results, anything from 55 to 100% faster frame-rates make good use of the extra horsepower within the premium Sony console. The average we saw from God of War 3 on the PS3 over a collection of battles was in the high 30’s to low 40’s. The performance mode delivers a 55fps average across this collection of heavier battles (aside the boss battles) and includes the heavy cinematic moments. Even if the game can have a few dips and judders from time to time, largely down to sector loading and Auto-Save points, in play across exploration and combat the action feels much smoother and consistent, enough for me to recommend it as the best way to play for 1080P Pro owners. The choice of these modes and the dual benefits they offer to us, the player, make them a worthy addition to the title and I am very please that these simple, preset choices that present a distinct and valued choice for all rather than forcing a method of play, Santa Monica Studios have prevailed, with the single most technically impressive and performant game they have created to date, and coming from the team that made God of War on PS2 and PS3, that is a statement I do not take lightly.PS4 owners can be safe in the knowledge that they have a powerhouse of a title to push the hardware as much as they have even seen, but still fit within the 30fps target 99% of the time as does the 4K presented Pro mode. With the icing on the cake allowing those very same Pro owners to get the best of both and a tour-de-force presentation that can still push the upper echelons of performance.
The games style and delivery, as a whole, is one that appears to have been driven by the artists and director over having technology in for the sake of it, not to say that technology is not used impressively here. The dynamic geometry based displacement snow system is possibly the most obvious, it is not a first with other titles using something similar over the years, but mixed with the particle system you get some incredible vista’s as snow drifts from the peaks. In battle the snow is deformed and removed dynamically, leaving tracks as characters walk, clumping away as they fall with a possible Parallax Occlusion Mapping (POM) integration. The results speak for themselves, with decals building up on Kratos, Atreus and all characters and then melting away it is standout boost to the engine. Another visual boost is the incredible hair and beard rendering the team added to their in-house engine, a requirement born out of Atreus looking too ill without hair. It has a genuine depth and volume to it, hair moves with character motion, various designs and heavy use across the title demonstrate the solution is a versatile one, covering hair, fur and beards alike.
Pump up the Volume
Volume of another sort comes from the Voxel based lighting solution, again this is becoming more and more common in games. Using a geometry based grid it can sometimes show up signs of errors that leave a block of Volumetric light hanging mid air as you move back, but these are rare. The solution is not limited to screen space, which allows light to stream in from above and through areas with a natural and impressive look to scenes that can be enjoyed from any angle and no emitters causing issues as they move off screen. Talking of screen space, reflections do at certain points adopt SSR, but by and large, they use Cube Maps mixed with light and image proxies to allow local reflections to appear accurate, some form of cube map warping allows these to work in many cases, but as is always the case with a probe based cubemap sample you can notice the errors and lower resolution of these at times on high reflective surfaces a minor blip. Other areas of manual adjustments and placements can also be noticed, the game uses Sub Surface scattering on skin and objects, a common requirement for PBR based material systems. Some easier methods can overlap a glowing decal or texture to emulate the effect such as on Kratos ear when near a bright light sources, but I am aware I am edging way into the nit picking realms. Something as vast, expansive, dynamic and non-linear as this title (yes, trust me) 100% perfection is simply unrealistic but they draw damn close, and even the mighty SSM are not gods.
Shadows have long since been an expensive and troublesome problem to resolve within realtime rendering and even though here the solutions are very good, many of those wide spread issues remain and will so until we see more ray-traced solutions creeping in alongside reflections. It uses a decent cascade level with filtering applied to them from a good distance out, equal on all machines just like the LOD. Dynamic shadow casting lights are also used in places, with them shifting the atmosphere accordingly. These are again of a decent resolution quality and cast of crevices and objects equally, it is also a good way to spot the resolution boost the Rez mode offers which includes a Bokeh sampled shaped on inner light seeps. Bokeh shapes are also used in the games Post Processed Depth of field, which adds a sense of scale, focus and overall cinematic look during the games plentiful cut-scenes, all of which are 100% real-time. This is all the more obvious as another technical first is the one shot camera system, so long as you get through the game without dying (which you won’t) from action, battle, cutscene and all the expansive world you can explore no loading or cut ever happens, a magnificent feat that really adds to the close and personal tale the game is going for and it works.
Thinking like a Jaguar
Another technical boost that does not get as much mention is the AI from Atreus, your little boy is a valid member of the team. I am confident Naughty Dog may have shared their techniques from the last of us, but here Atreus can explore, solve puzzles and fight alongside you without ever feeling like a hindrance. The collection of problems he solves and manages from path finding, combat and help with clues, not to mention being your translator. He can make jokes, observe local scenery, chat about events like a true 10yr old and genuinely convinces you he is a living, breathing person, rarely feeling stifled and anything but an integral ingredient to the story and Kratos humanity, co-op with a little Jaguar. He also portrays another feature, animation, more specifically fluidity of movement, IK solutions help drive the grounded movement of characters in games but the natural bend of arms or sway of body all need to come from the animation team. Most large scale games all create full skelatol meshes or rigs for the characters which are then skinned with the relevant textures and details required. But to move and animate these characters they use a combination of Pose Space Deformation or Shape keys and motion capture for the cinematics and fighting.
Shape keys are a skeletal driven animation system that allows joints to bend, turn and twist with a great level of accuracy and are another tool in the animator’s tool-kit. As you see swipes and swings from enemies, or climbing over a rocky surface you can almost mistake the entire animations in the game as mo-cap, which just underpins how successful they have been to integrate this into their engine and how seamlessly it everything blends together. The combat and the Axe is where you can really appreciate the leap in this regard, very easy to take for granted and drives the excellent and satisfying melee system in the title. Watch how many tiny touches are in something so simple as the axe, spinning through the air with a weight at the end affect its trajectory and spin. Hit box markers on enemies can be manipulated as you knock them back with a head strike or freeze them in place, throwing using R1 button gives a spin that can knock foes of their feet to move in for a more personal chat. Mixed in with this is the extra abilities you unlock and that core feature of retrieval is simply majestic and supremely realised here. A collection of foes can be hit on the way out and back, a shielded enemy will deflect, but pulled back from behind which you can control as you walk around the battlefield can take them off guard. This multiplexed attack system integrates incredible animation, physics and can be strung together in so many ways to make the combat feel unique, tactile and so damn awesome looking, certainly one of my favourite combat systems in any game at this point..incredible work.
The motion capture also includes faces and the leap here is a high as the details from last gen, hand based animations, although impressive, now stand out compared to the subtle details you can now pick up during these sections. Muscle movements of scowls or the wiping of a cheek add so much to the acting and emotion portrayed during these sequences that it would now be hard to go back, easily up with the best, thus far, this generation and the fact even non-human entries still portray the same level of details and emotion is equally as remarkable. To cap this list of incredible techniques and art packed into the game, destruction is another string to that bow. Although far from all encompassing, many elements of the world can be destroyed and broken through and crumble during battle. It simply increases the believably and construction of it as it can break into chunks during the epic battles that ensue alongside the puzzles also using elements of this organic granularity which only makes them natural to solve. It also stands as a prime example of the symbiotic relationship of tech and art that Santa Monica have perfectly manipulated here to magnificent results.
The Nordic world crafted here is one that has been 5 years in the making and a work of love, dedication and passion. The universal praise and early sales it has achieved are both appropriate and just rewards for all of that, Design led to give us a world that follows the principles of the real world but hyper-realistic in presentation. Using the technology to achieve those aims but never drive them,it is a success of monumental proportions on multiple levels. Sure, other games may push more technology into one package, but few others are close to the artistic flair, distinct design and majesty this new adventure offers. If this is the start of a whole new trilogy I am glad I got in at the ground floor, as the passion and care lavished on this is not only a sign Single Player games are loved, but is the only place we could experience such a magical take and technical marvel.If you enjoyed previous God of War games, you will love this and if you did not, this may just bring you round as it is an incredible reboot of the series and a character that was almost beyond redemption.
Kratos is back with a bang, still angry but no longer without reason, the God amongst Playstation has returned.
I was provided a review code from Sony Computer Entertainment Europe which allowed me to cover the title for review.