Monolith Soft says procedurally generating assets in Xenoblade Chronicles 3 ‘reduced man-hours considerably’
The studio says automating the creation of some of its 100,000 assets allowed more time to focus on gameplay
A trio of Monolith Soft developers have said that using procedural asset generation made it a lot easier to make Xenoblade Chronicles 3’s vast world map.
In an interview with Japanese publication CG World, map model designer Yoichi Akizuki, support engineer Mitsuhiro Hirose and programmer Takashi Shibahara discussed the studio’s gradual inclusion of procedural generation tools in software like Houdini into its development process.
Procedural asset generation lets developers create base 3D models, textures and defined rules to create an algorithm. This can then be used by software to automatically generate numerous assets that follow the same rules.
For example, a developer could create the 3D model and textures for a tree, then define the parameters of what a tree should look like, and the software will then generate a number of trees that all look different but follow the developer’s set guidelines.
Because procedural asset generation involves applying algorithms to base assets created by the developer itself, this is not the same as generative AI, which pulls data from other sources and has been criticised in recent years for its ability to potentially steal copyrighted artwork from other artists.
Xenoblade Chronicles 3, which was released in 2022, was praised for its enormous open world, and in CG World’s interview the trio explained that the introduction of software like Houdini made this a less time-consuming task, allowing developers to automate the creation of smaller, inconsequential assets and giving them more freedom to work on gameplay or other more important art assets.
Akizuki explained to the publication that the total number of assets was increasing with each new Xenoblade game, which made it increasingly more time-consuming to populate the vast worlds the series is known for.
“The main reason for the introduction [of procedural asset generation] was to cope with the increasing volume of assets required for games,” he said (via machine translation). “This has had a particularly significant impact on our game titles, which feature the exploration of vast and diverse fields.”
“In the past we managed to produce 1,000 to 2,000 assets manually, but now that number has increased to 100,000, which is impossible to keep up with manually.
“The conventional method had limitations in terms of cost and schedule. So we replaced the placement process with a procedural one and automated it, allowing us to focus our development resources on the actual game creation. We had been conducting basic research on Houdini for some time, but it was with Xenoblade Chronicles 3 that we were able to put it into practice for the first time as part of our asset placement system.”
When asked specifically what parts of development were made easier by procedural tech, Akizuki said it helped not only with the creation of assets, but also the collision detection.
“We have been able to significantly reduce the amount of work involved in placing detailed assets,” he said. “It is also being utilised in the basic collision processing that is unique to games. Collision is the ‘final key’ in game adjustment, so manual final adjustments are essential. So we automated 70% of the process using procedural techniques and adjusted the remaining 30% manually, which led to a significant reduction in man-hours.”
He added: “The more we reduce these man-hours, the more resources we can allocate to gameplay and visuals, which ultimately contributes to Houdini’s ability to enhance the value of the game.”
Shibahara also pointed out that Houdini software in particular lets technical artists and designers make tweaks to the world without necessarily having to get a programmer involved.
“With conventional automatic generation tool development, it was common for programmers and designers to be tied up for long periods of time,” he explained. “But now, with Houdini’s procedural foundation, the technical artists and designers can make adjustments directly. This frees up programmers to work on improving the environment, which is a win-win situation.”
Hirose then explained that Monolith’s R&D team was looking into more ways to use automatic generation, including the ability to create cityscapes.
“Designers only need to place grey boxes, and pressing a button automatically generates buildings,” he said. “Houses are constructed by arranging modules, and the system automatically calculates the appropriate number of floors based on the height of each module and the height of the boxes, then arranges them accordingly. Roofs are also assembled using modules, and the data is output in a format optimised for games.”
VGC’s Xenoblade Chronicles 3 review called the game Monolith Soft‘s “largest and most story-stuffed world yet”, praising the way it “finds more meaningful ways of filling a map with adventures”.
“Xenoblade Chronicles 3 delivers a massive world, and more than enough story and character to fill it, combined with the series’ most reactive combat system to date,” we wrote. “While certainly a monster commitment, Aionios is an incredible place to live for a month or two.”
