We are only a few days away from the release of the expansion Burning Shores For Horizon Forbidden Westbut Guerrilla Games still have plenty to tell us about this one. Community leader Narae Lee took advantage of a forum on the PlayStation-Blog to talk about technology next gen used to create a truer-than-life cloud sky.
Volumetric 3D clouds can thus be split with theHelionwing (sunwing), our new favorite mount.
The world of Horizon is vast and majestic. It is full of lush landscapes topped with endless skies. When the Guerrilla team started creating this world, developers from various disciplines wondered how to make the world as immersive as possible. For this purpose, the team in charge of the atmosphere decided to fill the sky with clouds larger than life.
In Horizon Forbidden West, the process of creating these clouds had already evolved a lot. And in the Burning Shores expansion, Aloy will soar through more realistic and breathtaking skies than ever before.
“The horizon evokes expanses as vast as the ocean, but also the curve that the clouds and the sun describe until reaching the earth at an immeasurable distance”, explains Andrew Schneider, senior special effects artist at Guerrilla. “Open-world game developers therefore face a daunting challenge. How to give the player the impression that the environment in which he evolves has no end? »
Asking the question was one thing, breaking the project down into technical tasks was another.
In the early 2010s, clouds for feature films and animated films were created using volumetric rendering techniques. In video games, the render time with high definition results and interactive frame rate was too much. The developers were aware, however, that this technique had the potential to be revolutionary.
Then, the material innovations that have emerged in recent years have changed the situation. With the advent of the PlayStation 4 console in 2015, Andrew partnered with Nathan Bos, Senior Tech Programmer at Guerrilla. Together, they developed the high-yield volumetric cloud system found in Horizon Zero Dawn. These painstakingly detailed cloud formations perfectly conveyed the optimism and beauty of the world in which Aloy moved. The system in question supported the changes implied by the passage of time, but also particularly realistic animations. The player therefore had the impression of moving in a living environment.
The foundations on which the team would build for Horizon Forbidden West were thus established.
In video games, clouds can translate a particular atmosphere. Just like the greenery, crystal clear waters, and rugged cliffs, the clouds of Horizon were meant to elicit emotion across the world. To do this, the developers could not just create white nets above Aloy’s head. The formations had to be fluctuating, varied and in high definition.
“We were inspired by luminist artists, such as Albert Bierstadt, a 19th century painter. These painters had no equal in depicting the interactions between clouds and dry land. They incorporated many details into their works to create a sense of space and thus produced truly spectacular landscapes.
To recreate this effect in 3D, we had to develop a way to model the clouds. In Horizon Zero Dawn, we used several methods to create the cloud formations. Voxels are blocks that can form volumetric 3D clouds. We had also created a cloud simulator and experimented with rendering 3D “voxel” data in real time.
But, from a technological point of view, it was too early for this method,” says Andrew. “The hardware and software weren’t advanced enough yet. We therefore had to opt for an effective method, but allowing to obtain high definition results. However, this required more work than the simulation. »
So we decided to paint fixed cloud layers, rather than individual formations. However, this process had to be improved, since it is possible to fly on the back of a machine in Horizon Forbidden West.
For the second installment in the series, Andrew and Nathan have therefore improved the rendering quality of the basic system used in Zero Dawn. They also made it support a new type of low altitude foggy clouds that the player could fly through. This allowed them to create truly stunning atmospheres, such as a storm with a vortex and lightning effects. The clouds were now a character in their own right and added to the feeling of atmospheric tension.
A new technical challenge
Naturally, the next step was to improve this system even further for Horizon Forbidden West: Burning Shores. For the expansion, the team optimized the experience using voxel technology and made various technical improvements around the world.
“The cloud system we developed for Horizon Zero Dawn and Horizon Forbidden West allowed us to work quickly because the clouds weren’t stored as 3D objects. These were actually instructions for creating 3D clouds from limited 2D information. The PlayStation 5 console can handle larger data sets. So, after we finished working on Horizon Forbidden West, we started writing a prototype voxel cloud renderer that would live up to our quality requirements. This was also to allow the player to fly through extremely detailed cloud formations. »
It is particularly difficult to achieve a balance between performance and quality when the player can be both on the ground and in the air. However, the prototype worked. We achieved dynamic results at high and low altitudes, not only thanks to many hours of work, but also thanks to the increased power of the PlayStation 5 console.
But it was not enough to create a single cloud. It was necessary to create an entire celestial landscape.
Andrew created ‘Frankencloudscapes’: towering cloud formations that allow a terrain modeler to treat the sky as a landscape in its own right. The clouds thus became a background element, but also an environment to explore.
To make this system work on the scale of Burning Shores, a Shock Squad was assembled at Guerrilla. The members of this team had the task of flying through the clouds in order to assess the performance and quality of the innovation. Andrew and Nathan then teamed up with Hugh Mala, a senior lead tech programmer.
They were then confronted with a purely technical obstacle: how to ensure that such amounts of volumetric voxel data are supported?
“Hugh and I broke down the problem and divided up the tasks. I made it so that we can add detail to low precision voxel data while rendering. During this time, Hugh did his best to compress the data so that it could be accessed more quickly from memory. Thanks to these two processes, the rendering of volumetric voxel clouds was much faster. But that still wasn’t enough,” says Andrew. “The most time-consuming aspect of this process was calculating cloud brightness. This is a particularly complicated operation. As a workaround, Nathan devised a process to reduce the rendering time to a speed suitable for high and standard frame rates. »
“It also turned out that, in this particular case, the optimization allowed us to obtain a better visual result. We were able to cast cloud-by-cloud shadows over much greater distances, for added realism. At this point, we therefore had a method allowing us to render volumetric clouds from the ground, but also directly in the air, when the player evolves in the middle of these formations. »
Next, the team had to tackle balancing. “The balance between quality and performance is particularly delicate,” continues Andrew. “Quality usually has an impact on processing. So whenever we improve the quality of our clouds, we have to make sure that it does not affect performance more than the system already in place. »
To achieve this balance, senior lead tech programmer and graphics engineer James McLaren helped the team understand how the code behaved on the PlayStation console itself. His expertise helped developers get the most out of the hardware by optimizing code for the PlayStation 5 console. “James’ input was fundamental early in development. That’s what allowed Guerrilla to push the envelope during production,” says Andrew.
Thanks to the work of the team, the player will therefore be able to launch himself through cloud formations as realistic and varied as the landscape he will have discovered on dry land. And all this on the back of Helionwing.
What awaits the player in Burning Shores
Traveling to the Burning Coast, Aloy will find some familiar faces and machines. She will also discover new ways to explore the world.
“Besides the main gameplay, we wanted to make the experience as entertaining and enjoyable as possible. Clouds aren’t just part of an immersive setting. It is an explorable landscape in its own right. Amidst these cloud formations, players will be able to explore tunnels, caves and other surprises that are sure to amuse them,” promises Andrew.
“The best part is that the experience will be different depending on when you decide to try these features. As the day progresses, the quality and direction of light changes. Certain characteristics therefore appear and disappear depending on the time of day, for always different journeys.
And, I wouldn’t want to spoil anything, but I hope lightning doesn’t scare you. »
THE sunwing however, won’t be the only creature we can tame in this adventure. There will also be THE waterwing (whose French name is still unknown), a mechanical winged monster that we can pilot underwateras we can see in a video of gameplay unprecedented.
Burning Shores will be available on April 19 for €19.99 on PS5 and you can still buy the base game from €58.43 on Amazon.co.uk.