Dating back to the early days when Forza Horizon 1 came out, it was truly astonishing to see, and the open world felt too good to be true. Looking back to that game 9 years later, it’s looking somewhat cheap and basic. Playground Games took racing to an open world and gave all cars their own fun playground. Since then, the Horizon series has further developed for almost a decade and, today, it’s one of the most complex racing games on the market.
However, the franchise got its true glow-up in 2016, when Playground Games decided to capture a crazy amount of photos of the sky and later convert that into a dynamic realistic-looking sky for Forza Horizon 3. Head of Playground Games, Ralph Fulton, spoke about the decision-making process and how complicated the ideas were:
We looked at Forza Horizon 2 and where we could improve. We built an incredible atmospheric simulation in our sky system in that game, which still exists in Forza Horizon 3 and is fundamental to the lighting; but when you see clouds in real-life, they morph and fold in on themselves, and that’s very difficult to do with traditional methods. However, it’s an effect we get with our camera.
How do you create a basic background?
Back in the good old Xbox 360 days, the developers would simply pick a blank image and use that as a background for the game. Then another one for night, and eventually a third one for rain. With the images, you compose a sky with a day and night cycle thanks to CGI (Computer-generated imagery). That’s how you could create a sky for a video game in case you would be on a tight budget, although Playground Games actually did put effort into that by adding clouds, stars, a moon, etc.
It does look a bit sketchy when you look directly at the sky since you can clearly see there’s a background behind the horizon. Of course, it’s a method that Playground Games could’ve kept, but added more weather types. That, however, did not meet Playground Games’ standards when creating Forza Horizon 3 because it wouldn’t look natural.
The new technology
In Forza Horizon 3, the studio went all in to rebuild the entire sky and lighting from scratch, as it did not keep up with the desirable beauty and realism. Thanks to previous successful titles, Playground Games had the resources to build a 12K High Dynamic Range. That would later be shipped to Australia and take photos of their pretty weather.
Now, the less fun part of this project was probably the cost. The rig, which consisted of 3 high-quality cameras, cost them a whopping £100,000, and the energy put into the project was devastating. The team would sit outside for months and capture the sky at different times of the day, different types of weather and patiently wait until they’ve gathered enough photos. Altogether, the photographers managed to take 2 million photos! Everything would be transferred back to the studio in the UK physically since you can’t email away files containing terabytes of images.
The same technique was used for Forza Horizon 5, where Playground games would set up a rig that consisted of three identical cameras, whereas each captured a third of the sky. Sewing these images together, you have a spherical image with a 12k resolution. After 400 hours spent under the hot shining sun in Mexico, you have enough images to make a sky.
And still, you cannot e-mail everything, as the team managed to bring home 75 terabytes of photos. Obviously, it’s taking up lots of space due to the high-resolution images. Doing the math, the cameras were programmed to take a photo at 30-second intervals. That’s just about 48,000 images that they put together to make such beautiful skies.
Issues during the development
Sky capturing is a new technique that at first seemed pretty crazy to Playground Games, but not so stupid once they tried it. It’s ineffective in many ways yet important for the Forza franchise. Although it may seem as easy as moving the rig, taking images, and directly send them back to the studio, the team encountered numerous issues during the development.
For instance, exposure and focus must be changed, whether you capture in daylight or at night. Imagine you take a photo of the moon; the stars wouldn’t appear in your photo. Raising the exposure time, you might be able to spot stars, but the moon would be a blank circle. To solve this problem, the editing team uses Lightroom to remove the stars and put “fake” ones. The stars would otherwise appear as blurry boxes in the sky and simply not fit in. Besides that, there are birds, dust and annoying bugs that photobomb right when the camera captures an image. These must be edited out. Now imagine doing this kind of work with almost 50,000 images.
When you put these images together, you no longer have a sketchy-looking sky and clouds that also fold on its own. And oh boy, such beautiful in-game photos you can capture! It’s almost like real life. It went from full computer editing to a super-advanced and time-consuming project, which should also explain why the Horizon series went from taking up less than 10 GB in the early days to almost 100 GB for Forza Horizon 5. If you’re still curious how this sort of technology works, the video explains the entire process and all the issues, respectively solutions.