Ghost of Yōtei has been a labor of affection for Sucker Punch, and we’re comfortable to have it out on the planet for everybody to play. Now that gamers have gotten a style of the sport, we thought this was an excellent alternative to speak a bit of bit in regards to the expertise that helped get us right here.
Coming off of what we achieved with Ghost of Tsushima, the mission imaginative and prescient for Ghost of Yōtei put a stronger emphasis on a participant’s sense of freedom in an untamed wilderness. This meant striving for much less intrusive methods to information gamers, stunning environments with longer sightlines, extra versatile weapon fight, memorable characters with persona, and emotional story moments. Attempting to do all this whereas sustaining an excellent body charge is clearly a problem.
So, let’s dig into a number of features of the expertise we used to create Ghost of Yōtei!
Wandering a wild world
In prototyping our imaginative and prescient without spending a dime exploration, we discovered it only if gamers might gaze throughout a good looking panorama and comply with their curiosity to seek out the sport. From a technical perspective, touchdown that feeling required longer sight strains, that means higher rendering for grass, terrain and mountains into the gap.
We improved the looks of distant mountains by baking fashions and detailed terrain supplies into textures that we might show at larger element. We additionally doubled the quantity of grass and renderable gadgets our GPU compute renderer is allowed to supply. On this shot, the distant mountains with over a million timber, rocks, and bushes are culled all the way down to about sixty thousand particular person gadgets that we render to generate our G-buffers to construct the ultimate picture.
We use procedural assisted authoring methods and lean closely on GPU compute to course of all of those situations effectively with out CPU involvement. This includes sequences of compute jobs to carry out occlusion culling, reminiscence allocation, fill out draw data earlier than we readback that data on the CPU to sew into the ultimate command lists for the body. Right here’s an animation of the same shot with all GPU drawn geometry animating into place to provide you a way of the size concerned. We use these methods for runtime generated knowledge as effectively like our broad fields of flowers, and even sometimes for issues like ropes and chains.
To present every space of the world a singular taste, we constructed interplay techniques that assist emphasize their themes. A lot of the world has grass or small crops, and along with deforming with wind and character movement, we added a system that renders weapon sweeps right into a “lower buffer.” This buffer is then sampled by cuttable geometry and is used to spawn particles with the geometry above the lower. This permits Atsu to chop most grass, flowers and small crops within the sport.
Hokkaido has Japan’s most excessive winters, so we needed to realistically painting the interplay of characters with deep snow. To assist that, we constructed a terrain tessellation system that each will increase the quantity of element that may be represented by the terrain, and which will be dynamically deformed at runtime. To attain this, particles and geometry are rendered to a displacement buffer as characters stroll, roll and struggle via it. This was versatile sufficient that we prolonged it to permit characters to knock snow off of timber and bushes, spawning snow particles within the course of. Once we mix that with a brand new snow sparkle impact utilizing steady screen-space noise, it finally ends up wanting like this.
Tall mountains like Mt. Yōtei are sometimes lined by clouds, so we needed to provide you with a means of rendering clouds in entrance of world geometry, which wasn’t potential in Ghost of Tsushima’s engine. We additionally needed to provide the impression of stormy, unsettled climate by rising the velocity at which clouds might transfer. To allow sooner cloud movement with out objectionable artifacts, we retailer the common seen depth of every texel within the cloud map (measured from the digital camera), which permits us to make use of parallax mapping methods whereas scrolling every cloud body. (We additionally mix three cloud frames as a substitute of simply two, which ends up in even smoother movement.) By additionally storing the common seen squared depth within the cloud map, we’re in a position to reconstruct a easy statistical distribution of the cloud opacity alongside every ray, and this lets us compute how a lot the clouds ought to obscure world geometry like mountains.
Fog and atmospheric scattering was an essential focus when establishing the artwork type of Ghost of Tsushima, and for Ghost of Yōtei we needed to construct on that by including assist for native fog volumes. These are computed effectively by utilizing the PS5’s expanded 16-bit floating level GPU directions. As a aspect impact of our cloud optimizations, we compute a light-space cloud shadow map, and this permits crepuscular rays (“god rays”) to be seen in our volumetric fog, even removed from the digital camera. We additionally let artists place “god ray targets” on the planet in order that they’re extra steadily lit by a gap within the clouds.
Character and motion
One in all our major objectives was to make the world of Ghost of Yōtei really feel alive. We wish all the pieces on the display to maneuver with the wind, together with all of the clothes characters put on, the tassels on weapons, and all the hanging fabric in settlements. Whenever you roll round and struggle, we wish to kick up mud and leaves whereas leaving you muddy and bloody, to essentially anchor you on the planet.
Atsu’s complicated costumes can solely transfer realistically because of the brand new layering assist we constructed into our high-performance GPU compute fabric system. Along with including assist for a number of layers of simulated fabric (seen beneath), we assist fabric collisions, and use a set of fastidiously tuned heuristics to simulate massive numbers of particular person fabric simulations effectively. Right here is an instance of Atsu in one among her extra complicated costumes, surrounded by transferring fabric.
GPU particles have been a robust go well with for Sucker Punch since Notorious Second Son. In Ghost of Yōtei we proceed so as to add to our bag of tips, permitting particles to pattern terrain materials, deformation and water movement. For instance, this shot reveals particles touchdown on and flowing down river.
Along with affecting the world, we anchor characters by having the world punch again. We do that by splatting data right into a directional grid deformed across the character which we then use to layer in texture results to make the character moist, bloody, muddy or snowy.
We additionally leverage our particle techniques to permit the participant to swap to the previous to discover Atsu’s household historical past. To swap between previous and current, we modify the skeleton and geometry of Atsu whereas preserving her character state and animation constant. Parts of the background and lighting are additionally modified immediately because of the velocity of the SSD with some fastidiously chosen prefetching. That is completed behind a curtain of animating particles which pattern a duplicate of the body buffer from simply earlier than the transition.
Ray Tracing and PS5 Professional enhancements
As a local PS5 sport, we knew we needed to enhance picture high quality by leveraging a number of the platform’s newer expertise. With the discharge of the PS5 Professional, we additionally needed to push in a course that may assist us with future video games. Primarily based on the strong assist from the PlayStation central expertise groups, we invested in two large areas: ray tracing, and picture upsampling with PSSR.
Since Ghost of Yōtei takes place within the wilderness of seventeenth century Hokkaido, there are few mirror-like surfaces that lend themselves to ray-traced reflections. As a substitute, we determined to make use of ray tracing to enhance the constancy of our world illumination answer. We attacked this from two instructions: first with a extra automated, improved baked lighting mannequin, which we might then increase with short-range ray-traced world illumination (RTGI). This required vital modifications to our mesh streaming format, permitting us to dynamically decompress the acceleration buildings utilized by the ray tracing {hardware}. By utilizing the PS5 Professional’s extra environment friendly ray tracing {hardware}, gamers can allow RTGI focusing on 60 frames per second on Professional consoles.
For Ghost of Yōtei we rebuilt our body to make use of a extra common dynamic decision algorithm, with upsampling, partly so we might make the most of PSSR. PSSR works very effectively for us with only some tweaks, together with operating conservative rasterization for small particles. By comparability, our commonplace upsampling algorithm requires considerably extra hinting and authoring assist to attain good outcomes. Right here’s a side-by-side look. For those who zoom in very shut (16x earlier than gif compression), you may see that PSSR does a greater job reconstructing tremendous particulars on structure and foliage. It is usually extra steady beneath movement.
Loading velocity
For a very long time, Sucker Punch has prided itself on getting gamers into our video games as shortly as potential. In Ghost of Yōtei we continued this custom by doubling down on quick load occasions.
We optimize loading by preprocessing knowledge in order that it requires solely a handful of SSD reads and patching operations per location or terrain tile to load gameplay-relevant knowledge. We then compute and cargo solely the feel mips and mesh LODs wanted to render the primary body, with one learn per ingredient. Right here’s what loading from the far south to the far north appears to be like like with out the display light out. (Word that that is considerably slower than it might be if we didn’t should render the world the entire time.)
All through improvement we “pet food” these techniques reasonably than utilizing a distinct loading mannequin for delivery builds. Canine fooding is programmer-speak for each programmer, artist and designer testing what we ship to enhance its high quality.
Conclusion
This can be a small peek into a number of the technical work we do at Sucker Punch. Making video games is greater than that although — it’s an enormous staff effort with artwork informing expertise and expertise informing artwork all through.
Once we started this mission 5 years in the past, our purpose was to construct a sport world that gamers would love getting misplaced in. A lot of our technical selections have been anchored across the core fantasy of Ghost of Yōtei — that of a wandering warrior coming to phrases with occasions from her previous. We’re thrilled to see this imaginative and prescient coming to life with gamers sharing their experiences and posting unimaginable in-game screenshots and movies utilizing Photograph Mode.
We’re definitely happy with the consequence and we hope everybody enjoys wandering the wilderness in Ghost of Yōtei.
For those who’re enthusiastic about extra information on Sucker Punch’s expertise and improvement course of, check out our previous shows at conferences like GDC and SIGGRAPH. We count on to share extra in 2026.
Particular because of Jasmin Patry, Doug Davis, and Eric Wohllaib who helped me edit and put together content material for this put up, in addition to all of the Sucker Punch people whose work I’m representing right here.
