The world of Horizon is vast and majestic, featuring lush landscapes covered in endless skies. We looked at how to bring the life of the level into the world. For Guerrilla’s Atmospherics team, this meant filling the sky with lifelike clouds.
This production has evolved for Horizon Forbidden West. And now, in Burning Shores, Aloy soars through the skies more breathtakingly realistic than ever before.
approach
“When I think of the horizon, I imagine vast expanses like the open ocean, with clouds and the sun arcing and touching them at unfathomable distances,” says Andrew Schneider, Principal FX Artist at Guerrilla. increase. “Open-world games present a metaphorically similar challenge to developers: How can we push the experience so that the player feels like they are in an environment of infinite possibilities? ?”
Asking a question was one thing, breaking it down into technical tasks was another.
In the early 2010s, feature film and animation VFX began using volume rendering to create clouds. For video games, this technique took too long to render quality results at interactive frame rates, but developers knew it could be game-changing.
Hardware innovations have begun to change this. In 2015 on the PlayStation 4 Nexus, Andrew partnered with Guerrilla’s principal tech programmer, Nathan Vos. Together they developed the highly efficient open-world volumetric cloud system seen in Horizon Zero Dawn. It was shaped like a thing. It supports time changes and realistic animations, creating a completely lifelike sense of the world.
This established the foundation the team would build for Horizon Forbidden West.
evolution
In video games, clouds help convey mood. Along with lush green clear water and steep cliffs, Horizon Clouds amazes the world. To accomplish this, they had to be more than the white twigs high above Aloy’s head. I needed movement, variety and definition.
“We looked to artists who were part of the Luminance movement, such as the 19th-century painter Albert Bierstadt, for inspiration. He mastered action, used light and detail to create spaces and created truly dramatic landscape paintings.
Albert Bierstadt, Storm Over the Sierra Nevada, 1870
“To reproduce this effect in 3D, we had to develop a way to model the clouds. It is a block that can build a 3D cloud.We actually created a cloud simulator and experimented with rendering 3D “voxel” data in real time. ”
“But technically, it was too early for this,” recalls Andrew. “The hardware and software were not at the right stage of development, so we decided to model the clouds with an efficient rendering method that produced high-quality results, while requiring more modeling work than simulation. bottom.”
The solution was to paint fixed cloud layers instead of individual layers. However, to support the addition of flying mounts in Horizon Forbidden West, we need to extend this process.
In the sequel, Andrew and Nathan have upgraded the rendering quality of the base system used in Zero Dawn and extended it to support new fog-like clouds that allow players to fly at low altitudes. This allowed for an awe-inspiring atmosphere, like a superstorm with ominous vortex movements and internal lightning effects. Now the clouds had their own character, gurgling with atmospheric tension.
Next technical issue
Naturally, the next step was to continue innovating this system for Horizon Forbidden West: Burning Shores. For the expansion, the team used voxel technology to enhance the experience and made many other technical improvements around the world.
“The cloud system that we developed for Horizon Zero Dawn and Horizon Forbidden West is not about storing clouds as 3D objects, but rather about creating 3D clouds from limited 2D information. It was fast because we were storing the instructions, the PlayStation 5 can handle much larger datasets, so after Forbidden West ended we were able to meet our quality standards and actually let the player have a very detailed cloud We started working on a voxel cloud renderer prototype that would allow us to fly through formations.”
Achieving a balance between performance and quality when the player is on the ground and in the air was an ambitious challenge. Still, the prototype paid off, producing dense and dynamic results at both low and high altitudes. This is a feat made possible by hard work and the increased power of the PlayStation 5.
But creating a single cloud was far from building a complete cloudscape.
Andrew created what he called “Frankencloudscapes”. This is a large cloud formation that allows terrain modelers to treat the sky like a landscape. As a result, the cloudscape served as both a background element and an exploration environment.
To make this work on the scale required for Burning Shores, Guerrilla’s strike team took on the challenge of flying in the clouds, a true test of performance and quality. Andrew has teamed up with his Nathan and brought on Senior Principal Tech his programmer Hugh Malan.
The first hurdle they faced was very technical. How do you handle huge amounts of volume voxel data?
“Hugh and I overcame this problem by splitting up. We developed a method to take low-detail voxel data and add detail during rendering. Combining these processes, rendering volumetric voxel clouds is exponentially faster.”
“But even that wasn’t fast enough,” recalls Andrew. “The most costly part of this process is the cloud lighting calculations, which are complex in themselves. To avoid this, Nathan reduced render times to speeds that worked in both standard and high frame rate modes. I designed a way to do that.”
“This was also one of the rare situations where the optimizations yielded better visual results. This allowed us to cast shadows from cloud to cloud much farther, improving realism. At this point, we had a way to render volumetric clouds on the ground and in the air right next to it.”
The second challenge was balancing. “There is a dance that real-time graphics engineers do to balance quality and performance,” he continues Andrew. “Quality usually comes with a ‘cost’ in terms of processing. So every time we improve the quality of the cloud, we have to do it at a cost equal to or less than the cost of the current cloud he system. ”
To find this balance, Senior Principal Tech Programmer and Graphics Engineer James McLaren helped the team understand how the code works at a low level on the PlayStation hardware itself. His expertise allowed us to get the most out of our hardware by optimizing the code for PlayStation 5.
Ultimately, the pieces stack up to give the player an awe-inspiring sensation of soaring in and around a cloudscape as precise and varied as the land below. Everything is behind the Sunwing.
What awaits at Burning Shores
Heading to Burning Shores, Aloy encounters familiar machines and faces. But she also discovers new ways to explore her own world.
“Outside of the main gameplay, it was important to make the experience fun and enjoyable. Caves and other surprises can be explored to make flying fun,” says Andrew.
“The best part is that your experience will be different depending on when you try these features. The atmosphere of the trip will change.
And I don’t want to spoil anything – but I hope you’re not afraid of a little lightning.
